2010 |
Andre, Ph. ; Men'shchikov, A; Bontemps, S; Koenyves, V; Motte, F; Schneider, N; Didelon, P; Minier, V; Saraceno, P; Ward-Thompson, D; Di Francesco, J; White, G; Molinari, S; Testi, L; Abergel, A; Griffin, M; Henning, Th. ; Royer, P; Merin, B; Vavrek, R; Attard, M; Arzoumanian, D; Wilson, C D; Ade, P; Aussel, H; Baluteau, J -P; Benedettini, M; Bernard, -Ph. J; Blommaert, J A D L; Cambresy, L; Cox, P; Di Giorgio, A; Hargrave, P; Hennemann, M; Huang, M; Kirk, J; Krause, O; Launhardt, R; Leeks, S; Le Pennec, J; Li, J Z; Martin, P G; Maury, A; Olofsson, G; Omont, A; Peretto, N; Pezzuto, S; Prusti, T; Roussel, H; Russeil, D; Sauvage, M; Sibthorpe, B; Sicilia-Aguilar, A; Spinoglio, L; Waelkens, C; Woodcraft, A; Zavagno, A From filamentary clouds to prestellar cores to the stellar IMF: Initial highlights from the Herschel Gould Belt Survey Journal Article In: ASTRONOMY & ASTROPHYSICS, 518 , 2010, ISSN: 0004-6361. @article{andre_filamentary_2010, title = {From filamentary clouds to prestellar cores to the stellar IMF: Initial highlights from the Herschel Gould Belt Survey}, author = {Andre, Ph. and Men'shchikov, A. and Bontemps, S. and Koenyves, V. and Motte, F. and Schneider, N. and Didelon, P. and Minier, V. and Saraceno, P. and Ward-Thompson, D. and Di Francesco, J. and White, G. and Molinari, S. and Testi, L. and Abergel, A. and Griffin, M. and Henning, Th. and Royer, P. and Merin, B. and Vavrek, R. and Attard, M. and Arzoumanian, D. and Wilson, C. D. and Ade, P. and Aussel, H. and Baluteau, J. -P. and Benedettini, M. and Bernard, J. -Ph. and Blommaert, J. A. D. L. and Cambresy, L. and Cox, P. and Di Giorgio, A. and Hargrave, P. and Hennemann, M. and Huang, M. and Kirk, J. and Krause, O. and Launhardt, R. and Leeks, S. and Le Pennec, J. and Li, J. Z. and Martin, P. G. and Maury, A. and Olofsson, G. and Omont, A. and Peretto, N. and Pezzuto, S. and Prusti, T. and Roussel, H. and Russeil, D. and Sauvage, M. and Sibthorpe, B. and Sicilia-Aguilar, A. and Spinoglio, L. and Waelkens, C. and Woodcraft, A. and Zavagno, A.}, doi = {10.1051/0004-6361/201014666}, issn = {0004-6361}, year = {2010}, date = {2010-08-01}, journal = {ASTRONOMY & ASTROPHYSICS}, volume = {518}, abstract = {We summarize the first results from the Gould Belt Survey, obtained toward the Aquila rift and Polaris Flare regions during the science demonstration phase of Herschel. Our 70-500 mu m images taken in parallel mode with the SPIRE and PACS cameras reveal a wealth of filamentary structure, as well as numerous dense cores embedded in the filaments. Between similar to 350 and 500 prestellar cores and similar to 45-60 Class 0 protostars can be identified in the Aquila field, while similar to 300 unbound starless cores and no protostars are observed in the Polaris field. The prestellar core mass function (CMF) derived for the Aquila region bears a strong resemblance to the stellar initial mass function (IMF), already confirming the close connection between the CMF and the IMF with much better statistics than earlier studies. Comparing and contrasting our Herschel results in Aquila and Polaris, we propose an observationally-driven scenario for core formation according to which complex networks of long, thin filaments form first within molecular clouds, and then the densest filaments fragment into a number of prestellar cores via gravitational instability.}, keywords = {}, pubstate = {published}, tppubtype = {article} } We summarize the first results from the Gould Belt Survey, obtained toward the Aquila rift and Polaris Flare regions during the science demonstration phase of Herschel. Our 70-500 mu m images taken in parallel mode with the SPIRE and PACS cameras reveal a wealth of filamentary structure, as well as numerous dense cores embedded in the filaments. Between similar to 350 and 500 prestellar cores and similar to 45-60 Class 0 protostars can be identified in the Aquila field, while similar to 300 unbound starless cores and no protostars are observed in the Polaris field. The prestellar core mass function (CMF) derived for the Aquila region bears a strong resemblance to the stellar initial mass function (IMF), already confirming the close connection between the CMF and the IMF with much better statistics than earlier studies. Comparing and contrasting our Herschel results in Aquila and Polaris, we propose an observationally-driven scenario for core formation according to which complex networks of long, thin filaments form first within molecular clouds, and then the densest filaments fragment into a number of prestellar cores via gravitational instability. |
Bendo, G J; Wilson, C D; Pohlen, M; Sauvage, M; Auld, R; Baes, M; Barlow, M J; Bock, J J; Boselli, A; Bradford, M; Buat, V; Castro-Rodriguez, N; Chanial, P; Charlot, S; Ciesla, L; Clements, D L; Cooray, A; Cormier, D; Cortese, L; Davies, J I; Dwek, E; Eales, S A; Elbaz, D; Galametz, M; Galliano, F; Gear, W K; Glenn, J; Gomez, H L; Griffin, M; Hony, S; Isaak, K G; Levenson, L R; Lu, N; Madden, S; O'Halloran, B; Okumura, K; Oliver, S; Page, M J; Panuzzo, P; Papageorgiou, A; Parkin, T J; Perez-Fournon, I; Rangwala, N; Rigby, E E; Roussel, H; Rykala, A; Sacchi, N; Schulz, B; Schirm, M R P; Smith, M W L; Spinoglio, L; Stevens, J A; Sundar, S; Symeonidis, M; Trichas, M; Vaccari, M; Vigroux, L; Wozniak, H; Wright, G S; Zeilinger, W W The Herschel Space Observatory view of dust in M81 Journal Article In: ASTRONOMY & ASTROPHYSICS, 518 , 2010, ISSN: 1432-0746. @article{bendo_herschel_2010, title = {The Herschel Space Observatory view of dust in M81}, author = {Bendo, G. J. and Wilson, C. D. and Pohlen, M. and Sauvage, M. and Auld, R. and Baes, M. and Barlow, M. J. and Bock, J. J. and Boselli, A. and Bradford, M. and Buat, V. and Castro-Rodriguez, N. and Chanial, P. and Charlot, S. and Ciesla, L. and Clements, D. L. and Cooray, A. and Cormier, D. and Cortese, L. and Davies, J. I. and Dwek, E. and Eales, S. A. and Elbaz, D. and Galametz, M. and Galliano, F. and Gear, W. K. and Glenn, J. and Gomez, H. L. and Griffin, M. and Hony, S. and Isaak, K. G. and Levenson, L. R. and Lu, N. and Madden, S. and O'Halloran, B. and Okumura, K. and Oliver, S. and Page, M. J. and Panuzzo, P. and Papageorgiou, A. and Parkin, T. J. and Perez-Fournon, I. and Rangwala, N. and Rigby, E. E. and Roussel, H. and Rykala, A. and Sacchi, N. and Schulz, B. and Schirm, M. R. P. and Smith, M. W. L. and Spinoglio, L. and Stevens, J. A. and Sundar, S. and Symeonidis, M. and Trichas, M. and Vaccari, M. and Vigroux, L. and Wozniak, H. and Wright, G. S. and Zeilinger, W. W.}, doi = {10.1051/0004-6361/201014568}, issn = {1432-0746}, year = {2010}, date = {2010-08-01}, journal = {ASTRONOMY & ASTROPHYSICS}, volume = {518}, abstract = {We use Herschel Space Observatory data to place observational constraints on the peak and Rayleigh-Jeans slope of dust emission observed at 70-500 mu m in the nearby spiral galaxy M81. We find that the ratios of wave bands between 160 and 500 mu m are primarily dependent on radius but that the ratio of 70 to 160 mu m emission shows no clear dependence on surface brightness or radius. These results along with analyses of the spectral energy distributions imply that the 160-500 mu m emission traces 15-30 K dust heated by evolved stars in the bulge and disc whereas the 70 mu m emission includes dust heated by the active galactic nucleus and young stars in star forming regions.}, keywords = {}, pubstate = {published}, tppubtype = {article} } We use Herschel Space Observatory data to place observational constraints on the peak and Rayleigh-Jeans slope of dust emission observed at 70-500 mu m in the nearby spiral galaxy M81. We find that the ratios of wave bands between 160 and 500 mu m are primarily dependent on radius but that the ratio of 70 to 160 mu m emission shows no clear dependence on surface brightness or radius. These results along with analyses of the spectral energy distributions imply that the 160-500 mu m emission traces 15-30 K dust heated by evolved stars in the bulge and disc whereas the 70 mu m emission includes dust heated by the active galactic nucleus and young stars in star forming regions. |
Eales, S A; Smith, M W L; Wilson, C D; Bendo, G J; Cortese, L; Pohlen, M; Boselli, A; Gomez, H L; Auld, R; Baes, M; Barlow, M J; Bock, J J; Bradford, M; Buat, V; Castro-Rodriguez, N; Chanial, P; Charlot, S; Ciesla, L; Clements, D L; Cooray, A; Cormier, D; Davies, J I; Dwek, E; Elbaz, D; Galametz, M; Galliano, F; Gear, W K; Glenn, J; Griffin, M; Hony, S; Isaak, K G; Levenson, L R; Lu, N; Madden, S; O'Halloran, B; Okumura, K; Oliver, S; Page, M J; Panuzzo, P; Papageorgiou, A; Parkin, T J; Perez-Fournon, I; Rangwala, N; Rigby, E E; Roussel, H; Rykala, A; Sacchi, N; Sauvage, M; Schulz, B; Schirm, M R P; Spinoglio, L; Srinivasan, S; Stevens, J A; Symeonidis, M; Trichas, M; Vaccari, M; Vigroux, L; Wozniak, H; Wright, G S; Zeilinger, W W Mapping the interstellar medium in galaxies with Herschel Journal Article In: ASTRONOMY & ASTROPHYSICS, 518 , 2010, ISSN: 0004-6361. @article{eales_mapping_2010, title = {Mapping the interstellar medium in galaxies with Herschel}, author = {Eales, S. A. and Smith, M. W. L. and Wilson, C. D. and Bendo, G. J. and Cortese, L. and Pohlen, M. and Boselli, A. and Gomez, H. L. and Auld, R. and Baes, M. and Barlow, M. J. and Bock, J. J. and Bradford, M. and Buat, V. and Castro-Rodriguez, N. and Chanial, P. and Charlot, S. and Ciesla, L. and Clements, D. L. and Cooray, A. and Cormier, D. and Davies, J. I. and Dwek, E. and Elbaz, D. and Galametz, M. and Galliano, F. and Gear, W. K. and Glenn, J. and Griffin, M. and Hony, S. and Isaak, K. G. and Levenson, L. R. and Lu, N. and Madden, S. and O'Halloran, B. and Okumura, K. and Oliver, S. and Page, M. J. and Panuzzo, P. and Papageorgiou, A. and Parkin, T. J. and Perez-Fournon, I. and Rangwala, N. and Rigby, E. E. and Roussel, H. and Rykala, A. and Sacchi, N. and Sauvage, M. and Schulz, B. and Schirm, M. R. P. and Spinoglio, L. and Srinivasan, S. and Stevens, J. A. and Symeonidis, M. and Trichas, M. and Vaccari, M. and Vigroux, L. and Wozniak, H. and Wright, G. S. and Zeilinger, W. W.}, doi = {10.1051/0004-6361/201014536}, issn = {0004-6361}, year = {2010}, date = {2010-08-01}, journal = {ASTRONOMY & ASTROPHYSICS}, volume = {518}, abstract = {The standard method of mapping the interstellar medium in a galaxy, by observing the molecular gas in the CO 1-0 line and the atomic gas in the 21-cm line, is largely limited with current telescopes to galaxies in the nearby universe. In this letter, we use SPIRE observations of the galaxies M99 and M100 to explore the alternative approach of mapping the interstellar medium using the continuum emission from the dust. We have compared the methods by measuring the relationship between the star-formation rate and the surface density of gas in the galaxies using both methods. We find the two methods give relationships with a similar dispersion, confirming that observing the continuum emission from the dust is a promising method of mapping the interstellar medium in galaxies.}, keywords = {}, pubstate = {published}, tppubtype = {article} } The standard method of mapping the interstellar medium in a galaxy, by observing the molecular gas in the CO 1-0 line and the atomic gas in the 21-cm line, is largely limited with current telescopes to galaxies in the nearby universe. In this letter, we use SPIRE observations of the galaxies M99 and M100 to explore the alternative approach of mapping the interstellar medium using the continuum emission from the dust. We have compared the methods by measuring the relationship between the star-formation rate and the surface density of gas in the galaxies using both methods. We find the two methods give relationships with a similar dispersion, confirming that observing the continuum emission from the dust is a promising method of mapping the interstellar medium in galaxies. |
Gomez, H L; Baes, M; Cortese, L; Smith, M W L; Boselli, A; Ciesla, L; Bendo, G J; Pohlen, M; di Alighieri, Serego S; Auld, R; Barlow, M J; Bock, J J; Bradford, M; Buat, V; Castro-Rodriguez, N; Chanial, P; Charlot, S; Clements, D L; Cooray, A; Cormier, D; Davies, J I; Dwek, E; Eales, S; Elbaz, D; Galametz, M; Galliano, F; Gear, W K; Glenn, J; Griffin, M; Hony, S; Isaak, K G; Levenson, L R; Lu, N; Madden, S; O'Halloran, B; Okumura, K; Oliver, S; Page, M J; Panuzzo, P; Papageorgiou, A; Parkin, T J; Perez-Fournon, I; Rangwala, N; Rigby, E E; Roussel, H; Rykala, A; Sacchi, N; Sauvage, M; Schirm, M R P; Schulz, B; Spinoglio, L; Srinivasan, S; Stevens, J A; Symeonidis, M; Trichas, M; Vaccari, M; Vigroux, L; Wilson, C D; Wozniak, H; Wright, G S; Zeilinger, W W The dust morphology of the elliptical Galaxy M 86 with SPIRE Journal Article In: ASTRONOMY & ASTROPHYSICS, 518 , 2010, ISSN: 0004-6361. @article{gomez_dust_2010, title = {The dust morphology of the elliptical Galaxy M 86 with SPIRE}, author = {Gomez, H. L. and Baes, M. and Cortese, L. and Smith, M. W. L. and Boselli, A. and Ciesla, L. and Bendo, G. J. and Pohlen, M. and Alighieri, S. di Serego and Auld, R. and Barlow, M. J. and Bock, J. J. and Bradford, M. and Buat, V. and Castro-Rodriguez, N. and Chanial, P. and Charlot, S. and Clements, D. L. and Cooray, A. and Cormier, D. and Davies, J. I. and Dwek, E. and Eales, S. and Elbaz, D. and Galametz, M. and Galliano, F. and Gear, W. K. and Glenn, J. and Griffin, M. and Hony, S. and Isaak, K. G. and Levenson, L. R. and Lu, N. and Madden, S. and O'Halloran, B. and Okumura, K. and Oliver, S. and Page, M. J. and Panuzzo, P. and Papageorgiou, A. and Parkin, T. J. and Perez-Fournon, I. and Rangwala, N. and Rigby, E. E. and Roussel, H. and Rykala, A. and Sacchi, N. and Sauvage, M. and Schirm, M. R. P. and Schulz, B. and Spinoglio, L. and Srinivasan, S. and Stevens, J. A. and Symeonidis, M. and Trichas, M. and Vaccari, M. and Vigroux, L. and Wilson, C. D. and Wozniak, H. and Wright, G. S. and Zeilinger, W. W.}, doi = {10.1051/0004-6361/201014530}, issn = {0004-6361}, year = {2010}, date = {2010-08-01}, journal = {ASTRONOMY & ASTROPHYSICS}, volume = {518}, abstract = {We present Herschel-SPIRE observations at 250-500 mu m of the giant elliptical galaxy M 86 and examine the distribution of the resolved cold dust emission and its relation with other galactic tracers. The SPIRE images reveal three dust components: emission from the central region; a dust lane extending north-south; and a bright emission feature 10 kpc to the south-east. We estimate that similar to 10(6) M(circle dot) of dust is spatially coincident with atomic and ionized hydrogen, originating from stripped material from the nearby spiral NGC 4438 due to recent tidal interactions with M 86. The gas-to-dust ratio of the cold gas component ranges from similar to 20-80. We discuss the different heating mechanisms for the dust features.}, keywords = {}, pubstate = {published}, tppubtype = {article} } We present Herschel-SPIRE observations at 250-500 mu m of the giant elliptical galaxy M 86 and examine the distribution of the resolved cold dust emission and its relation with other galactic tracers. The SPIRE images reveal three dust components: emission from the central region; a dust lane extending north-south; and a bright emission feature 10 kpc to the south-east. We estimate that similar to 10(6) M(circle dot) of dust is spatially coincident with atomic and ionized hydrogen, originating from stripped material from the nearby spiral NGC 4438 due to recent tidal interactions with M 86. The gas-to-dust ratio of the cold gas component ranges from similar to 20-80. We discuss the different heating mechanisms for the dust features. |
Gordon, K D; Galliano, F; Hony, S; Bernard, J -P; Bolatto, A; Bot, C; Engelbracht, C; Hughes, A; Israel, F P; Kemper, F; Kim, S; Li, A; Madden, S C; Matsuura, M; Meixner, M; Misselt, K; Okumura, K; Panuzzo, P; Rubio, M; Reach, W T; Roman-Duval, J; Sauvage, M; Skibba, R; Tielens, A G G M Determining dust temperatures and masses in the Herschel era: The importance of observations longward of 200 micron Journal Article In: ASTRONOMY & ASTROPHYSICS, 518 , 2010, ISSN: 1432-0746. @article{gordon_determining_2010, title = {Determining dust temperatures and masses in the Herschel era: The importance of observations longward of 200 micron}, author = {Gordon, K. D. and Galliano, F. and Hony, S. and Bernard, J. -P. and Bolatto, A. and Bot, C. and Engelbracht, C. and Hughes, A. and Israel, F. P. and Kemper, F. and Kim, S. and Li, A. and Madden, S. C. and Matsuura, M. and Meixner, M. and Misselt, K. and Okumura, K. and Panuzzo, P. and Rubio, M. and Reach, W. T. and Roman-Duval, J. and Sauvage, M. and Skibba, R. and Tielens, A. G. G. M.}, doi = {10.1051/0004-6361/201014541}, issn = {1432-0746}, year = {2010}, date = {2010-08-01}, journal = {ASTRONOMY & ASTROPHYSICS}, volume = {518}, abstract = {Context. The properties of the dust grains (e.g., temperature and mass) can be derived from fitting far-IR SEDs (textbackslashtextbackslashtextgreater= 100 mu m). Only with SPIRE on Herschel has it been possible to get high spatial resolution at 200 to 500 mu m that is beyond the peak (similar to 160 mu m) of dust emission in most galaxies. Aims. We investigate the differences in the fitted dust temperatures and masses determined using only textbackslashtextbackslashtextless200 mu m data and then also including textbackslashtextbackslashtextgreater200 mu m data (new SPIRE observations) to determine how important having textbackslashtextbackslashtextgreater200 mu m data is for deriving these dust properties. Methods. We fit the 100 to 350 mu m observations of the Large Magellanic Cloud (LMC) point-by-point with a model that consists of a single temperature and fixed emissivity law. The data used are existing observations at 100 and 160 mu m (from IRAS and Spitzer) and new SPIRE observations of 1/4 of the LMC observed for the HERITAGE key project as part of the Herschel science demonstration phase. Results. The dust temperatures and masses computed using only 100 and 160 mu m data can differ by up to 10% and 36%, respectively, from those that also include the SPIRE 250 & 350 mu m data. We find that an emissivity law proportional to lambda(-1.5) minimizes the 100-350 mu m fractional residuals. We find that the emission at 500 mu m is similar to 10% higher than expected from extrapolating the fits made at shorter wavelengths. We find the fractional 500 mu m excess is weakly anti-correlated with MIPS 24 mu m flux and the total gas surface density. This argues against a flux calibration error as the origin of the 500 mu m excess. Our results do not allow us to distinguish between a systematic variation in the wavelength dependent emissivity law or a population of very cold dust only detectable at lambda textbackslashtextbackslashtextgreater= 500 mu m for the origin of the 500 mu m excess.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Context. The properties of the dust grains (e.g., temperature and mass) can be derived from fitting far-IR SEDs (textbackslashtextbackslashtextgreater= 100 mu m). Only with SPIRE on Herschel has it been possible to get high spatial resolution at 200 to 500 mu m that is beyond the peak (similar to 160 mu m) of dust emission in most galaxies. Aims. We investigate the differences in the fitted dust temperatures and masses determined using only textbackslashtextbackslashtextless200 mu m data and then also including textbackslashtextbackslashtextgreater200 mu m data (new SPIRE observations) to determine how important having textbackslashtextbackslashtextgreater200 mu m data is for deriving these dust properties. Methods. We fit the 100 to 350 mu m observations of the Large Magellanic Cloud (LMC) point-by-point with a model that consists of a single temperature and fixed emissivity law. The data used are existing observations at 100 and 160 mu m (from IRAS and Spitzer) and new SPIRE observations of 1/4 of the LMC observed for the HERITAGE key project as part of the Herschel science demonstration phase. Results. The dust temperatures and masses computed using only 100 and 160 mu m data can differ by up to 10% and 36%, respectively, from those that also include the SPIRE 250 & 350 mu m data. We find that an emissivity law proportional to lambda(-1.5) minimizes the 100-350 mu m fractional residuals. We find that the emission at 500 mu m is similar to 10% higher than expected from extrapolating the fits made at shorter wavelengths. We find the fractional 500 mu m excess is weakly anti-correlated with MIPS 24 mu m flux and the total gas surface density. This argues against a flux calibration error as the origin of the 500 mu m excess. Our results do not allow us to distinguish between a systematic variation in the wavelength dependent emissivity law or a population of very cold dust only detectable at lambda textbackslashtextbackslashtextgreater= 500 mu m for the origin of the 500 mu m excess. |
Barluenga, Sofia ; Jogireddy, Rajamalleswaramma ; Koripelly, Girish K; Winssinger, Nicolas In Vivo Efficacy of Natural Product-Inspired Irreversible Kinase Inhibitors Journal Article In: CHEMBIOCHEM, 11 (12), pp. 1692–1699, 2010, ISSN: 1439-4227. @article{barluenga_vivo_2010, title = {In Vivo Efficacy of Natural Product-Inspired Irreversible Kinase Inhibitors}, author = {Barluenga, Sofia and Jogireddy, Rajamalleswaramma and Koripelly, Girish K. and Winssinger, Nicolas}, doi = {10.1002/cbic.201000205}, issn = {1439-4227}, year = {2010}, date = {2010-08-01}, journal = {CHEMBIOCHEM}, volume = {11}, number = {12}, pages = {1692--1699}, abstract = {Hypothemycin and related resorcylic acid lactones (RAL) bearing a cis-enone moiety have emerged as an alternative pharmacophore to heterocyclic motifs for kinase inhibition, and are endowed with a unique selectivity filter based on the irreversible reaction with a subset of the kinome bearing a suitably positioned cysteine residue. Two prototypical examples of “edited” RAL were evaluated for antitumoral, antimetastatic and antiangiogenic efficacy in an orthotopic murine renal cell carcinoma (RENCA) model. Both compounds (3 and 5) are good inhibitors of VEGFRs in vitro, and inhibited tumor growth in vivo with comparable efficacy to sunitinib, an FDA-approved VEGFRs inhibitor Compound 3 promoted lung metastasis to a similar extent as sunitinib, while compound 5 strongly inhibited lung metastasis. This study attests to the potential of irreversible kinase inhibitors and molecular editing of natural pharmacophores and provides encouraging results to a clinically significant problem}, keywords = {}, pubstate = {published}, tppubtype = {article} } Hypothemycin and related resorcylic acid lactones (RAL) bearing a cis-enone moiety have emerged as an alternative pharmacophore to heterocyclic motifs for kinase inhibition, and are endowed with a unique selectivity filter based on the irreversible reaction with a subset of the kinome bearing a suitably positioned cysteine residue. Two prototypical examples of “edited” RAL were evaluated for antitumoral, antimetastatic and antiangiogenic efficacy in an orthotopic murine renal cell carcinoma (RENCA) model. Both compounds (3 and 5) are good inhibitors of VEGFRs in vitro, and inhibited tumor growth in vivo with comparable efficacy to sunitinib, an FDA-approved VEGFRs inhibitor Compound 3 promoted lung metastasis to a similar extent as sunitinib, while compound 5 strongly inhibited lung metastasis. This study attests to the potential of irreversible kinase inhibitors and molecular editing of natural pharmacophores and provides encouraging results to a clinically significant problem |
Sauvage, M; Sacchi, N; Bendo, G J; Boselli, A; Pohlen, M; Wilson, C D; Auld, R; Baes, M; Barlow, M J; Bock, J J; Bradford, M; Buat, V; Castro-Rodriguez, N; Chanial, P; Charlot, S; Ciesla, L; Clements, D L; Cooray, A; Cormier, D; Cortese, L; Davies, J I; Dwek, E; Eales, S A; Elbaz, D; Galametz, M; Galliano, F; Gear, W K; Glenn, J; Gomez, H L; Griffin, M; Hony, S; Isaak, K G; Levenson, L R; Lu, N; Madden, S C; O'Halloran, B; Okumura, K; Oliver, S; Page, M J; Panuzzo, P; Papageorgiou, A; Parkin, T J; Perez-Fournon, I; Rangwala, N; Rigby, E E; Roussel, H; Rykala, A; Schulz, B; Schirm, M R P; Smith, M W L; Spinoglio, L; Stevens, J A; Srinivasan, S; Symeonidis, M; Trichas, M; Vaccari, M; Vigroux, L; Wozniak, H; Wright, G S; Zeilinger, W W The central region of spiral galaxies as seen by Herschel Journal Article In: ASTRONOMY & ASTROPHYSICS, 518 , 2010, ISSN: 0004-6361. @article{sauvage_central_2010, title = {The central region of spiral galaxies as seen by Herschel}, author = {Sauvage, M. and Sacchi, N. and Bendo, G. J. and Boselli, A. and Pohlen, M. and Wilson, C. D. and Auld, R. and Baes, M. and Barlow, M. J. and Bock, J. J. and Bradford, M. and Buat, V. and Castro-Rodriguez, N. and Chanial, P. and Charlot, S. and Ciesla, L. and Clements, D. L. and Cooray, A. and Cormier, D. and Cortese, L. and Davies, J. I. and Dwek, E. and Eales, S. A. and Elbaz, D. and Galametz, M. and Galliano, F. and Gear, W. K. and Glenn, J. and Gomez, H. L. and Griffin, M. and Hony, S. and Isaak, K. G. and Levenson, L. R. and Lu, N. and Madden, S. C. and O'Halloran, B. and Okumura, K. and Oliver, S. and Page, M. J. and Panuzzo, P. and Papageorgiou, A. and Parkin, T. J. and Perez-Fournon, I. and Rangwala, N. and Rigby, E. E. and Roussel, H. and Rykala, A. and Schulz, B. and Schirm, M. R. P. and Smith, M. W. L. and Spinoglio, L. and Stevens, J. A. and Srinivasan, S. and Symeonidis, M. and Trichas, M. and Vaccari, M. and Vigroux, L. and Wozniak, H. and Wright, G. S. and Zeilinger, W. W.}, doi = {10.1051/0004-6361/201014588}, issn = {0004-6361}, year = {2010}, date = {2010-08-01}, journal = {ASTRONOMY & ASTROPHYSICS}, volume = {518}, abstract = {With appropriate spatial resolution, images of spiral galaxies in thermal infrared (similar to 10 mu m and beyond) often reveal a bright central component, distinct from the stellar bulge, superimposed on a disk with prominent spiral arms. ISO and Spitzer studies have shown that much of the scatter in the mid-infrared colors of spiral galaxies is related to changes in the relative importance of these two components, rather than to other modifications, such as the morphological type or star formation rate, that affect the properties of the galaxy as a whole. With the Herschel imaging capability from 70 to 500 mu m, we revisit this two-component approach at longer wavelengths, to see if it still provides a working description of the brightness distribution of galaxies, and to determine its implications on the interpretation of global far-infrared properties of galaxies. We quantify the luminosity of the central component by both a decomposition of the radial surface brightness profile and a direct extraction in 2D. We find the central component contribution is variable within the three galaxies in our sample, possibly connected more directly to the presence of a bar than to the morphological type. The central component's relative contribution is at its maximum in the mid-infrared range and drops around 160 mu m to reach a constant value beyond 200 mu m. The central component contains a greater fraction of hot dust than the disk component, and while the colors of the central components are scattered, colors of the disk components are more homogenous from one galaxy to the next.}, keywords = {}, pubstate = {published}, tppubtype = {article} } With appropriate spatial resolution, images of spiral galaxies in thermal infrared (similar to 10 mu m and beyond) often reveal a bright central component, distinct from the stellar bulge, superimposed on a disk with prominent spiral arms. ISO and Spitzer studies have shown that much of the scatter in the mid-infrared colors of spiral galaxies is related to changes in the relative importance of these two components, rather than to other modifications, such as the morphological type or star formation rate, that affect the properties of the galaxy as a whole. With the Herschel imaging capability from 70 to 500 mu m, we revisit this two-component approach at longer wavelengths, to see if it still provides a working description of the brightness distribution of galaxies, and to determine its implications on the interpretation of global far-infrared properties of galaxies. We quantify the luminosity of the central component by both a decomposition of the radial surface brightness profile and a direct extraction in 2D. We find the central component contribution is variable within the three galaxies in our sample, possibly connected more directly to the presence of a bar than to the morphological type. The central component's relative contribution is at its maximum in the mid-infrared range and drops around 160 mu m to reach a constant value beyond 200 mu m. The central component contains a greater fraction of hot dust than the disk component, and while the colors of the central components are scattered, colors of the disk components are more homogenous from one galaxy to the next. |
Scholz, Roland ; Sidler, Corinne L; Thali, Ramon F; Winssinger, Nicolas ; Cheung, Peter C F; Neumann, Dietbert Autoactivation of Transforming Growth Factor beta-activated Kinase 1 Is a Sequential Bimolecular Process Journal Article In: JOURNAL OF BIOLOGICAL CHEMISTRY, 285 (33), pp. 25753–25766, 2010, ISSN: 0021-9258. @article{scholz_autoactivation_2010, title = {Autoactivation of Transforming Growth Factor beta-activated Kinase 1 Is a Sequential Bimolecular Process}, author = {Scholz, Roland and Sidler, Corinne L. and Thali, Ramon F. and Winssinger, Nicolas and Cheung, Peter C. F. and Neumann, Dietbert}, doi = {10.1074/jbc.M109.093468}, issn = {0021-9258}, year = {2010}, date = {2010-08-01}, journal = {JOURNAL OF BIOLOGICAL CHEMISTRY}, volume = {285}, number = {33}, pages = {25753--25766}, abstract = {Transforming growth factor-beta-activated kinase 1 (TAK1), an MAP3K, is a key player in processing a multitude of inflammatory stimuli. TAK1 autoactivation involves the interplay with TAK1-binding proteins (TAB), e. g. TAB1 and TAB2, and phosphorylation of several activation segment residues. However, the TAK1 autoactivation is not yet fully understood on the molecular level due to the static nature of available x-ray structural data and the complexity of cellular systems applied for investigation. Here, we established a bacterial expression system to generate recombinant mammalian TAK1 complexes. Co-expression of TAK1 and TAB1, but not TAB2, resulted in a functional and active TAK1-TAB1 complex capable of directly activating full-length heterotrimeric mammalian AMP-activated protein kinase (AMPK) in vitro. TAK1-dependent AMPK activation was mediated via hydrophobic residues of the AMPK kinase domain alpha G-helix as observed in vitro and in transfected cell culture. Co-immunoprecipitation of differently epitope-tagged TAK1 from transfected cells and mutation of hydrophobic alpha G-helix residues in TAK1 point to an intermolecular mechanism of TAB1-induced TAK1 autoactivation, as TAK1 autophosphorylation of the activation segment was impaired in these mutants. TAB1 phosphorylation was enhanced in a subset of these mutants, indicating a critical role of alpha G-helix residues in this process. Analyses of phosphorylation site mutants of the activation segment indicate that autophosphorylation of Ser-192 precedes TAB1 phosphorylation and is followed by sequential phosphorylation of Thr-178, Thr-187, and finally Thr-184. Finally, we present a model for the chronological order of events governing TAB1-induced TAK1 autoactivation.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Transforming growth factor-beta-activated kinase 1 (TAK1), an MAP3K, is a key player in processing a multitude of inflammatory stimuli. TAK1 autoactivation involves the interplay with TAK1-binding proteins (TAB), e. g. TAB1 and TAB2, and phosphorylation of several activation segment residues. However, the TAK1 autoactivation is not yet fully understood on the molecular level due to the static nature of available x-ray structural data and the complexity of cellular systems applied for investigation. Here, we established a bacterial expression system to generate recombinant mammalian TAK1 complexes. Co-expression of TAK1 and TAB1, but not TAB2, resulted in a functional and active TAK1-TAB1 complex capable of directly activating full-length heterotrimeric mammalian AMP-activated protein kinase (AMPK) in vitro. TAK1-dependent AMPK activation was mediated via hydrophobic residues of the AMPK kinase domain alpha G-helix as observed in vitro and in transfected cell culture. Co-immunoprecipitation of differently epitope-tagged TAK1 from transfected cells and mutation of hydrophobic alpha G-helix residues in TAK1 point to an intermolecular mechanism of TAB1-induced TAK1 autoactivation, as TAK1 autophosphorylation of the activation segment was impaired in these mutants. TAB1 phosphorylation was enhanced in a subset of these mutants, indicating a critical role of alpha G-helix residues in this process. Analyses of phosphorylation site mutants of the activation segment indicate that autophosphorylation of Ser-192 precedes TAB1 phosphorylation and is followed by sequential phosphorylation of Thr-178, Thr-187, and finally Thr-184. Finally, we present a model for the chronological order of events governing TAB1-induced TAK1 autoactivation. |
Martynov, Alexander G; Gurbunova, Yulia G; Tsivadze, Aslan Yu. ; Sauvage, Jean-Pierre 1,2-Dicyano-4,5-bis[2 `-(2 `'-benzyloxyethoxy)ethoxy]benzene - precursor towards new functionalized phthalocyanines Journal Article In: MENDELEEV COMMUNICATIONS, 20 (4), pp. 237–238, 2010, ISSN: 0959-9436. @article{martynov_12-dicyano-45-bis[2_2010, title = {1,2-Dicyano-4,5-bis[2 `-(2 `'-benzyloxyethoxy)ethoxy]benzene - precursor towards new functionalized phthalocyanines}, author = {Martynov, Alexander G. and Gurbunova, Yulia G. and Tsivadze, Aslan Yu. and Sauvage, Jean-Pierre}, doi = {10.1016/j.mencom.2010.06.019}, issn = {0959-9436}, year = {2010}, date = {2010-08-01}, journal = {MENDELEEV COMMUNICATIONS}, volume = {20}, number = {4}, pages = {237--238}, abstract = {1,2-Dicyano-4,5-bis[2'-(2 `'-benzyloxyethoxy)ethoxy]benzene can act as a precursor to new functionalized phthalocyanines with liquid crystal properties.}, keywords = {}, pubstate = {published}, tppubtype = {article} } 1,2-Dicyano-4,5-bis[2'-(2 `'-benzyloxyethoxy)ethoxy]benzene can act as a precursor to new functionalized phthalocyanines with liquid crystal properties. |
Aouani, Heykel ; Itzhakov, Stella ; Gachet, David ; Devaux, Eloise ; Ebbesen, Thomas W; Rigneault, Herve ; Oron, Dan ; Wenger, Jerome Colloidal Quantum Dots as Probes of Excitation Field Enhancement in Photonic Antennas Journal Article In: ACS NANO, 4 (8), pp. 4571–4578, 2010, ISSN: 1936-0851. @article{aouani_colloidal_2010, title = {Colloidal Quantum Dots as Probes of Excitation Field Enhancement in Photonic Antennas}, author = {Aouani, Heykel and Itzhakov, Stella and Gachet, David and Devaux, Eloise and Ebbesen, Thomas W. and Rigneault, Herve and Oron, Dan and Wenger, Jerome}, doi = {10.1021/nn1009209}, issn = {1936-0851}, year = {2010}, date = {2010-08-01}, journal = {ACS NANO}, volume = {4}, number = {8}, pages = {4571--4578}, abstract = {Optical antennas are essential devices to interface light to nanoscale volumes and locally enhance the electromagnetic intensity. Various experimental methods can be used to quantify the antenna amplification on the emission process, yet characterizing the antenna amplification at the excitation frequency solely is a challenging task. Such experimental characterization is highly needed to fully understand and optimize the antenna response. Here, we describe a novel experimental tool to directly measure the antenna amplification on the excitation field independently of the emission process. We monitor the transient emission dynamics of colloidal quantum dots and show that the ratio of doubly to singly excited state photoluminescence decay amplitudes is an accurate tool to quantify the local excitation intensity amplification. This effect is demonstrated on optical antennas made of polystyrene microspheres and gold nanoapertures, and supported by numerical computations. The increased doubly excited state formation on nanoantennas realizes a new demonstration of enhanced light-matter interaction at the nanoscale.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Optical antennas are essential devices to interface light to nanoscale volumes and locally enhance the electromagnetic intensity. Various experimental methods can be used to quantify the antenna amplification on the emission process, yet characterizing the antenna amplification at the excitation frequency solely is a challenging task. Such experimental characterization is highly needed to fully understand and optimize the antenna response. Here, we describe a novel experimental tool to directly measure the antenna amplification on the excitation field independently of the emission process. We monitor the transient emission dynamics of colloidal quantum dots and show that the ratio of doubly to singly excited state photoluminescence decay amplitudes is an accurate tool to quantify the local excitation intensity amplification. This effect is demonstrated on optical antennas made of polystyrene microspheres and gold nanoapertures, and supported by numerical computations. The increased doubly excited state formation on nanoantennas realizes a new demonstration of enhanced light-matter interaction at the nanoscale. |
Sondergaard, Thomas ; Bozhevolnyi, Sergey I; Novikov, Sergey M; Beermann, Jonas ; Devaux, Eloise ; Ebbesen, Thomas W Extraordinary Optical Transmission Enhanced by Nanofocusing Journal Article In: NANO LETTERS, 10 (8), pp. 3123–3128, 2010, ISSN: 1530-6984. @article{sondergaard_extraordinary_2010, title = {Extraordinary Optical Transmission Enhanced by Nanofocusing}, author = {Sondergaard, Thomas and Bozhevolnyi, Sergey I. and Novikov, Sergey M. and Beermann, Jonas and Devaux, Eloise and Ebbesen, Thomas W.}, doi = {10.1021/nl101873g}, issn = {1530-6984}, year = {2010}, date = {2010-08-01}, journal = {NANO LETTERS}, volume = {10}, number = {8}, pages = {3123--3128}, abstract = {We demonstrate that the phenomenon of extraordinary optical transmission (COT) through perforated metal films can be further boosted up by utilizing nanofocusing of radiation in tapered slits. For one-dimensional arrays of tapered slits in optically thick suspended gold films, we show that the maximum transmission at resonance is achieved for taper angles in the range of 7-10 degrees increasing significantly in comparison with the transmission by straight slits. Transmission spectroscopy of fabricated 500 and 700 nm period tapered slits in a 180 nm thick gold film on a glass substrate demonstrates the enhanced COT with the resonance transmission being as high as similar to 0.18 for the filling ratio of similar to 0.13 and showing good correspondence with theoretical results. It is also shown that the enhanced transmission can be achieved with either weak (2.5%) or strong (43%) reflection depending on the direction of light (normal) incidence.}, keywords = {}, pubstate = {published}, tppubtype = {article} } We demonstrate that the phenomenon of extraordinary optical transmission (COT) through perforated metal films can be further boosted up by utilizing nanofocusing of radiation in tapered slits. For one-dimensional arrays of tapered slits in optically thick suspended gold films, we show that the maximum transmission at resonance is achieved for taper angles in the range of 7-10 degrees increasing significantly in comparison with the transmission by straight slits. Transmission spectroscopy of fabricated 500 and 700 nm period tapered slits in a 180 nm thick gold film on a glass substrate demonstrates the enhanced COT with the resonance transmission being as high as similar to 0.18 for the filling ratio of similar to 0.13 and showing good correspondence with theoretical results. It is also shown that the enhanced transmission can be achieved with either weak (2.5%) or strong (43%) reflection depending on the direction of light (normal) incidence. |
Spichty, Martin ; Cecchini, Marco ; Karplus, Martin Conformational Free-Energy Difference of a Miniprotein from Nonequilibrium Simulations Journal Article In: JOURNAL OF PHYSICAL CHEMISTRY LETTERS, 1 (13), pp. 1922–1926, 2010, ISSN: 1948-7185. @article{spichty_conformational_2010, title = {Conformational Free-Energy Difference of a Miniprotein from Nonequilibrium Simulations}, author = {Spichty, Martin and Cecchini, Marco and Karplus, Martin}, doi = {10.1021/jz1005016}, issn = {1948-7185}, year = {2010}, date = {2010-07-01}, journal = {JOURNAL OF PHYSICAL CHEMISTRY LETTERS}, volume = {1}, number = {13}, pages = {1922--1926}, abstract = {Conformational free-energy differences are essential thermodynamic quantities for understanding the function of many biomolecules. They are accessible from computer simulations, but their accurate calculation is a challenging task. Here nonequilibrium computer simulations and the differential fluctuation theorem are used to evaluate, the free-energy difference between two conformational states of a structured miniprotein, the beta-hairpin of protein G, with an implicit treatment of the solvent. A molecular dynamics-based protocol is employed for the simulation of rapid switches between the conformational states in both the forward and the reverse direction. From the work performed on the system in the individual switches, the conformational free-energy difference is determined by use of the differential fluctuation theorem. The results are in excellent agreement with reference calculations from a long molecular dynamics simulation and from the confinement method. The nonequilibrium approach is a computationally efficient method for the calculation of conformational free-energy differences for biological systems.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Conformational free-energy differences are essential thermodynamic quantities for understanding the function of many biomolecules. They are accessible from computer simulations, but their accurate calculation is a challenging task. Here nonequilibrium computer simulations and the differential fluctuation theorem are used to evaluate, the free-energy difference between two conformational states of a structured miniprotein, the beta-hairpin of protein G, with an implicit treatment of the solvent. A molecular dynamics-based protocol is employed for the simulation of rapid switches between the conformational states in both the forward and the reverse direction. From the work performed on the system in the individual switches, the conformational free-energy difference is determined by use of the differential fluctuation theorem. The results are in excellent agreement with reference calculations from a long molecular dynamics simulation and from the confinement method. The nonequilibrium approach is a computationally efficient method for the calculation of conformational free-energy differences for biological systems. |
Reneme, Y; Dhainaut, F; Trentesaux, M; Ravanbakhsh, B; Granger, P; Dujardin, C; Gengembre, L; De Cola, P L XPS investigation of surface changes during thermal aging of Natural Gas Vehicle catalysts: Influence of Rh addition to Pd Journal Article In: SURFACE AND INTERFACE ANALYSIS, 42 (6-7, SI), pp. 530–535, 2010, ISSN: 0142-2421. @article{reneme_xps_2010, title = {XPS investigation of surface changes during thermal aging of Natural Gas Vehicle catalysts: Influence of Rh addition to Pd}, author = {Reneme, Y. and Dhainaut, F. and Trentesaux, M. and Ravanbakhsh, B. and Granger, P. and Dujardin, C. and Gengembre, L. and De Cola, P. L.}, doi = {10.1002/sia.3215}, issn = {0142-2421}, year = {2010}, date = {2010-07-01}, journal = {SURFACE AND INTERFACE ANALYSIS}, volume = {42}, number = {6-7, SI}, pages = {530--535}, abstract = {This study investigates thermal aging induced effects on the surface properties of model and commercial automotive catalysts for Natural Gas Vehicles, by means of X-ray photoelectron spectroscopy and infrared spectroscopy of chemisorbed CO as a probe molecule for noble metals. Post-combustion catalysts for this application are essentially composed of palladium containing low amounts of rhodium and additives to improve the oxygen storage properties. The aging procedure involved exposing the catalysts to an oxidizing atmosphere containing air and 10 vol.% H(2)O at 980 degrees C for 4 h in order to simulate surface changes which may occur under usual three-way operating conditions. It was found that sintering processes led to a significant loss of Pd concentration on model and commercial catalysts. Regarding Rh, diffusion processes into alumina also take place, which are partially inhibited on model catalysts when Rh interacts with Pd. Greater stabilization of Rh species is suggested on commercial catalysts in the presence of oxygen storage materials. Copyright (C) 2010 John Wiley & Sons, Ltd.}, keywords = {}, pubstate = {published}, tppubtype = {article} } This study investigates thermal aging induced effects on the surface properties of model and commercial automotive catalysts for Natural Gas Vehicles, by means of X-ray photoelectron spectroscopy and infrared spectroscopy of chemisorbed CO as a probe molecule for noble metals. Post-combustion catalysts for this application are essentially composed of palladium containing low amounts of rhodium and additives to improve the oxygen storage properties. The aging procedure involved exposing the catalysts to an oxidizing atmosphere containing air and 10 vol.% H(2)O at 980 degrees C for 4 h in order to simulate surface changes which may occur under usual three-way operating conditions. It was found that sintering processes led to a significant loss of Pd concentration on model and commercial catalysts. Regarding Rh, diffusion processes into alumina also take place, which are partially inhibited on model catalysts when Rh interacts with Pd. Greater stabilization of Rh species is suggested on commercial catalysts in the presence of oxygen storage materials. Copyright (C) 2010 John Wiley & Sons, Ltd. |
Latini, Gianluca ; Winroth, Gustaf ; Brovelli, Sergio ; McDonnell, Shane O; Anderson, Harry L; Mativetsky, Jeffrey M; Samori, Paolo ; Cacialli, Franco Enhanced luminescence properties of highly threaded conjugated polyelectrolytes with potassium counter-ions upon blending with poly(ethylene oxide) Journal Article In: JOURNAL OF APPLIED PHYSICS, 107 (12), 2010, ISSN: 0021-8979. @article{latini_enhanced_2010, title = {Enhanced luminescence properties of highly threaded conjugated polyelectrolytes with potassium counter-ions upon blending with poly(ethylene oxide)}, author = {Latini, Gianluca and Winroth, Gustaf and Brovelli, Sergio and McDonnell, Shane O. and Anderson, Harry L. and Mativetsky, Jeffrey M. and Samori, Paolo and Cacialli, Franco}, doi = {10.1063/1.3372616}, issn = {0021-8979}, year = {2010}, date = {2010-06-01}, journal = {JOURNAL OF APPLIED PHYSICS}, volume = {107}, number = {12}, abstract = {The photophysics and electroluminescence (EL) of thin films of unthreaded and cyclodextrin-encapsulated poly(4,4'-diphenylenevinylene) (PDV) with potassium countercations, blended with poly(ethylene oxide) (PEO) are investigated as a function of the PEO concentration. We show that three main factors contribute to increasing the photoluminescence (PL) quantum efficiency as a result of suppressed intermolecular interactions, namely: the high degree of encapsulation of the polyrotaxanes, the relatively large countercation (e.g., compared to lithium), and the complexation of the rotaxanes with PEO. By facilitating cationic transport to the negative electrodes, PEO also leads to devices with enhanced electron injection and improved charge balance, whose operation therefore resembles that of “virtually unipolar” light-emitting electrochemical cells. This effect, together with the enhanced PL efficiency, leads to higher EL efficiency for both polyrotaxanes and unthreaded polymers, upon addition of the PEO. We show that the concurrent exploitation of the various strategies above lead to an overall EL efficiency that is approximately twice the value previously reported for Li-based PDV. A blueshift of the EL spectrum during the devices turn-on is also reported and analyzed in terms of interference and doping effects. 2010 American Institute of Physics. [doi:10.1063/1.3372616]}, keywords = {}, pubstate = {published}, tppubtype = {article} } The photophysics and electroluminescence (EL) of thin films of unthreaded and cyclodextrin-encapsulated poly(4,4'-diphenylenevinylene) (PDV) with potassium countercations, blended with poly(ethylene oxide) (PEO) are investigated as a function of the PEO concentration. We show that three main factors contribute to increasing the photoluminescence (PL) quantum efficiency as a result of suppressed intermolecular interactions, namely: the high degree of encapsulation of the polyrotaxanes, the relatively large countercation (e.g., compared to lithium), and the complexation of the rotaxanes with PEO. By facilitating cationic transport to the negative electrodes, PEO also leads to devices with enhanced electron injection and improved charge balance, whose operation therefore resembles that of “virtually unipolar” light-emitting electrochemical cells. This effect, together with the enhanced PL efficiency, leads to higher EL efficiency for both polyrotaxanes and unthreaded polymers, upon addition of the PEO. We show that the concurrent exploitation of the various strategies above lead to an overall EL efficiency that is approximately twice the value previously reported for Li-based PDV. A blueshift of the EL spectrum during the devices turn-on is also reported and analyzed in terms of interference and doping effects. 2010 American Institute of Physics. [doi:10.1063/1.3372616] |
Rao, Francesco ; Karplus, Martin Protein dynamics investigated by inherent structure analysis Journal Article In: PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA, 107 (20), pp. 9152–9157, 2010, ISSN: 0027-8424. @article{rao_protein_2010, title = {Protein dynamics investigated by inherent structure analysis}, author = {Rao, Francesco and Karplus, Martin}, doi = {10.1073/pnas.0915087107}, issn = {0027-8424}, year = {2010}, date = {2010-05-01}, journal = {PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA}, volume = {107}, number = {20}, pages = {9152--9157}, abstract = {Molecular dynamics (MD) simulations provide essential information about the thermodynamics and dynamics of proteins. To construct the free-energy surface from equilibrium trajectories, it is necessary to group the individual snapshots in a meaningful way. The inherent structures (IS) are shown to provide an appropriate discretization of the trajectory and to avoid problems that can arise in clustering algorithms that have been employed previously. The IS-based approach is illustrated with a 30-ns room temperature “native” state MD simulation of a 10-residue peptide in a beta-hairpin conformation. The transitions between the IS are used to construct a configuration space network from which a one-dimensional free-energy profile is obtained with the mincut method. The results demonstrate that the IS approach is useful and that even for this simple system, there exists a nontrivial organization of the native state into several valleys separated by barriers as high as 3 kcal/mol. Further, by introducing a coarse-grained network, it is demonstrated that there are multiple pathways connecting the valleys. This scenario is hidden when the snapshots of the trajectory are used directly with rmsd clustering to compute the free-energy profile. Application of the IS approach to the native state of the PDZ2 signaling domain indicates its utility for the study of biologically relevant systems.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Molecular dynamics (MD) simulations provide essential information about the thermodynamics and dynamics of proteins. To construct the free-energy surface from equilibrium trajectories, it is necessary to group the individual snapshots in a meaningful way. The inherent structures (IS) are shown to provide an appropriate discretization of the trajectory and to avoid problems that can arise in clustering algorithms that have been employed previously. The IS-based approach is illustrated with a 30-ns room temperature “native” state MD simulation of a 10-residue peptide in a beta-hairpin conformation. The transitions between the IS are used to construct a configuration space network from which a one-dimensional free-energy profile is obtained with the mincut method. The results demonstrate that the IS approach is useful and that even for this simple system, there exists a nontrivial organization of the native state into several valleys separated by barriers as high as 3 kcal/mol. Further, by introducing a coarse-grained network, it is demonstrated that there are multiple pathways connecting the valleys. This scenario is hidden when the snapshots of the trajectory are used directly with rmsd clustering to compute the free-energy profile. Application of the IS approach to the native state of the PDZ2 signaling domain indicates its utility for the study of biologically relevant systems. |
Ulrich, Sebastien ; Petitjean, Anne ; Lehn, Jean-Marie Metallo-Controlled Dynamic Molecular Tweezers: Design, Synthesis, and Self-Assembly by Metal-Ion Coordination Journal Article In: EUROPEAN JOURNAL OF INORGANIC CHEMISTRY, (13), pp. 1913–1928, 2010, ISSN: 1434-1948. @article{ulrich_metallo-controlled_2010, title = {Metallo-Controlled Dynamic Molecular Tweezers: Design, Synthesis, and Self-Assembly by Metal-Ion Coordination}, author = {Ulrich, Sebastien and Petitjean, Anne and Lehn, Jean-Marie}, doi = {10.1002/ejic.200901262}, issn = {1434-1948}, year = {2010}, date = {2010-05-01}, journal = {EUROPEAN JOURNAL OF INORGANIC CHEMISTRY}, number = {13}, pages = {1913--1928}, abstract = {The introduction of controllable dynamic features into synthetic receptors represents a step towards “smart” adaptive nanodevices. We report herein our studies on the construction of dynamic molecular tweezers in which the binding of a substrate is allosterically controlled through shape switching of the receptor induced by metal-ion coordination. 1D, 2D NMR spectroscopy and X-ray crystallography were used to identify the nature of the metallosupramolecular entity generated. The presence of large aromatic naphthalene diimide moieties on the scaffold of the molecular tweezers. strongly influences their coordination-driven self-assembly. It was found that these additional stacking interactions lead to the cooperative formation of a homocomplex, to the self-sorted assembly of a hetero complex, and to the binding of non-coordinating aromatic guests.}, keywords = {}, pubstate = {published}, tppubtype = {article} } The introduction of controllable dynamic features into synthetic receptors represents a step towards “smart” adaptive nanodevices. We report herein our studies on the construction of dynamic molecular tweezers in which the binding of a substrate is allosterically controlled through shape switching of the receptor induced by metal-ion coordination. 1D, 2D NMR spectroscopy and X-ray crystallography were used to identify the nature of the metallosupramolecular entity generated. The presence of large aromatic naphthalene diimide moieties on the scaffold of the molecular tweezers. strongly influences their coordination-driven self-assembly. It was found that these additional stacking interactions lead to the cooperative formation of a homocomplex, to the self-sorted assembly of a hetero complex, and to the binding of non-coordinating aromatic guests. |
Jogireddy, Rajamalleswaramma ; Barluenga, Sofia ; Winssinger, Nicolas Molecular Editing of Kinase-Targeting Resorcylic Acid Lactones (RAL): Fluoroenone RAL Journal Article In: CHEMMEDCHEM, 5 (5), pp. 670–673, 2010, ISSN: 1860-7179. @article{jogireddy_molecular_2010, title = {Molecular Editing of Kinase-Targeting Resorcylic Acid Lactones (RAL): Fluoroenone RAL}, author = {Jogireddy, Rajamalleswaramma and Barluenga, Sofia and Winssinger, Nicolas}, doi = {10.1002/cmdc.201000047}, issn = {1860-7179}, year = {2010}, date = {2010-05-01}, journal = {CHEMMEDCHEM}, volume = {5}, number = {5}, pages = {670--673}, keywords = {}, pubstate = {published}, tppubtype = {article} } |
Collin, Jean-Paul ; Durola, Fabien ; Frey, Julien ; Heitz, Valerie ; Reviriego, Felipe ; Sauvage, Jean-Pierre ; Trolez, Yann ; Rissanen, Kari Templated Synthesis of Cyclic [4]Rotaxanes Consisting of Two Stiff Rods Threaded through Two Bis-macrocycles with a Large and Rigid Central Plate as Spacer Journal Article In: JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, 132 (19), pp. 6840–6850, 2010, ISSN: 0002-7863. @article{collin_templated_2010, title = {Templated Synthesis of Cyclic [4]Rotaxanes Consisting of Two Stiff Rods Threaded through Two Bis-macrocycles with a Large and Rigid Central Plate as Spacer}, author = {Collin, Jean-Paul and Durola, Fabien and Frey, Julien and Heitz, Valerie and Reviriego, Felipe and Sauvage, Jean-Pierre and Trolez, Yann and Rissanen, Kari}, doi = {10.1021/ja101759w}, issn = {0002-7863}, year = {2010}, date = {2010-05-01}, journal = {JOURNAL OF THE AMERICAN CHEMICAL SOCIETY}, volume = {132}, number = {19}, pages = {6840--6850}, abstract = {Two related cyclic [4]rotaxanes consisting of double macrocycles and rigid rods incorporating two bidentate chelates have each been prepared in high yield. The first step is a multigathering and threading reaction driven by coordination of two different bidentate chelates (part of either the rings or the rods) to each copper(I) center so as to afford the desired precursor. In both cases, the assembly step is done under very mild conditions, and it is quantitative. The second key reaction is the stopper-attaching reaction, based on click chemistry. Even if the quadruple stoppering reaction is not quantitative, it is relatively high-yielding (60% and 95%), and the copper-driven assembly process is carried out at room temperature without any aggressive reagent. The final copper-complexed [4]rotaxanes obtained contain two aromatic plates roughly parallel to one another located at the center of each bis-macrocycle. In the most promising case in terms of host-guest properties, the plates are zinc(II) porphyrins of the tetra-aryl series. The compounds have been fully characterized by various spectroscopic techniques ((1)H NMR, mass spectrometry, and electronic absorption spectroscopy). Unexpectedly, the copper-complexed porphyrinic [4]rotaxane could be crystallized as its 4PF(6)(-) salt to afford X-ray quality crystals. The structure obtained is in perfect agreement with the postulated chemical structure of the compound. It is particularly attractive in terms of symmetry and molecular aesthetics. The distance between the zinc atoms of the two porphyrins is 8.673 angstrom, which is sufficient to allow insertion between the two porphyrinic plates of small ditopic basic substrates able to interact with the central porphyrinic Zn atoms. This prediction has been confirmed by absorption spectroscopy measurements in the presence of various organic substrates. However, large substrates cannot be introduced in the corresponding recognition site and are thus complexed mostly in an exo fashion, being located outside the receptor cavity. Noteworthy, the stability constants of the 1:1 host-guest complexes are high (10(7) M(-1)).}, keywords = {}, pubstate = {published}, tppubtype = {article} } Two related cyclic [4]rotaxanes consisting of double macrocycles and rigid rods incorporating two bidentate chelates have each been prepared in high yield. The first step is a multigathering and threading reaction driven by coordination of two different bidentate chelates (part of either the rings or the rods) to each copper(I) center so as to afford the desired precursor. In both cases, the assembly step is done under very mild conditions, and it is quantitative. The second key reaction is the stopper-attaching reaction, based on click chemistry. Even if the quadruple stoppering reaction is not quantitative, it is relatively high-yielding (60% and 95%), and the copper-driven assembly process is carried out at room temperature without any aggressive reagent. The final copper-complexed [4]rotaxanes obtained contain two aromatic plates roughly parallel to one another located at the center of each bis-macrocycle. In the most promising case in terms of host-guest properties, the plates are zinc(II) porphyrins of the tetra-aryl series. The compounds have been fully characterized by various spectroscopic techniques ((1)H NMR, mass spectrometry, and electronic absorption spectroscopy). Unexpectedly, the copper-complexed porphyrinic [4]rotaxane could be crystallized as its 4PF(6)(-) salt to afford X-ray quality crystals. The structure obtained is in perfect agreement with the postulated chemical structure of the compound. It is particularly attractive in terms of symmetry and molecular aesthetics. The distance between the zinc atoms of the two porphyrins is 8.673 angstrom, which is sufficient to allow insertion between the two porphyrinic plates of small ditopic basic substrates able to interact with the central porphyrinic Zn atoms. This prediction has been confirmed by absorption spectroscopy measurements in the presence of various organic substrates. However, large substrates cannot be introduced in the corresponding recognition site and are thus complexed mostly in an exo fashion, being located outside the receptor cavity. Noteworthy, the stability constants of the 1:1 host-guest complexes are high (10(7) M(-1)). |
Mahboub, O; Carretero Palacios, S; Genet, C; Garcia-Vidal, F J; Rodrigo, Sergio G; Martin-Moreno, L; Ebbesen, T W Optimization of bull's eye structures for transmission enhancement Journal Article In: OPTICS EXPRESS, 18 (11), pp. 11292–11299, 2010, ISSN: 1094-4087. @article{mahboub_optimization_2010, title = {Optimization of bull's eye structures for transmission enhancement}, author = {Mahboub, O. and Carretero Palacios, S. and Genet, C. and Garcia-Vidal, F. J. and Rodrigo, Sergio G. and Martin-Moreno, L. and Ebbesen, T. W.}, doi = {10.1364/OE.18.011292}, issn = {1094-4087}, year = {2010}, date = {2010-05-01}, journal = {OPTICS EXPRESS}, volume = {18}, number = {11}, pages = {11292--11299}, abstract = {We present an exhaustive exploration of the parameter space defining the optical properties of a bull's eye structure, both experimentally and theoretically. By studying the resonance intensity variations associated with the different geometrical features, several parameters are seen to be interlinked and scale laws emerge. From the results it is possible to give a simple recipe to design a bull's eye structure with optimal transmission properties. (C) 2010 Optical Society of America}, keywords = {}, pubstate = {published}, tppubtype = {article} } We present an exhaustive exploration of the parameter space defining the optical properties of a bull's eye structure, both experimentally and theoretically. By studying the resonance intensity variations associated with the different geometrical features, several parameters are seen to be interlinked and scale laws emerge. From the results it is possible to give a simple recipe to design a bull's eye structure with optimal transmission properties. (C) 2010 Optical Society of America |
Karplus, Martin Role of conformation transitions in adenylate kinase Journal Article In: PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA, 107 (17), pp. E71, 2010, ISSN: 0027-8424. @article{karplus_role_2010, title = {Role of conformation transitions in adenylate kinase}, author = {Karplus, Martin}, doi = {10.1073/pnas.1002180107}, issn = {0027-8424}, year = {2010}, date = {2010-04-01}, journal = {PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA}, volume = {107}, number = {17}, pages = {E71}, keywords = {}, pubstate = {published}, tppubtype = {article} } |
Cecchini, Marco ; Alexeev, Yuri ; Karplus, Martin Pi Release from Myosin: A Simulation Analysis of Possible Pathways Journal Article In: STRUCTURE, 18 (4), pp. 458–470, 2010, ISSN: 0969-2126. @article{cecchini_pi_2010, title = {Pi Release from Myosin: A Simulation Analysis of Possible Pathways}, author = {Cecchini, Marco and Alexeev, Yuri and Karplus, Martin}, doi = {10.1016/j.str.2010.01.014}, issn = {0969-2126}, year = {2010}, date = {2010-04-01}, journal = {STRUCTURE}, volume = {18}, number = {4}, pages = {458--470}, abstract = {The release of phosphate (Pi) is an important element in actomyosin function and has been shown to be accelerated by the binding of myosin to actin. To provide information about the structural elements important for Pi release, possible escape pathways from various isolated myosin II structures have been determined by molecular dynamics simulations designed for studying such slow processes. The residues forming the pathways were identified and their role was evaluated by mutant simulations. Pi release is slow in the pre-powerstroke structure, an important element in preventing the powerstroke prior to actin binding, and is much more rapid for Pi modeled into the post-rigor and rigor-like structures. The previously proposed backdoor route is dominant in the pre-powerstroke and post-rigor states, whereas a different path is most important in the rigor-like state. This finding suggests a mechanism for the actin-activated acceleration of Pi release.}, keywords = {}, pubstate = {published}, tppubtype = {article} } The release of phosphate (Pi) is an important element in actomyosin function and has been shown to be accelerated by the binding of myosin to actin. To provide information about the structural elements important for Pi release, possible escape pathways from various isolated myosin II structures have been determined by molecular dynamics simulations designed for studying such slow processes. The residues forming the pathways were identified and their role was evaluated by mutant simulations. Pi release is slow in the pre-powerstroke structure, an important element in preventing the powerstroke prior to actin binding, and is much more rapid for Pi modeled into the post-rigor and rigor-like structures. The previously proposed backdoor route is dominant in the pre-powerstroke and post-rigor states, whereas a different path is most important in the rigor-like state. This finding suggests a mechanism for the actin-activated acceleration of Pi release. |
Karplus, Martin Dynamical aspects of molecular recognition Introduction Journal Article In: JOURNAL OF MOLECULAR RECOGNITION, 23 (2, SI), pp. 102–104, 2010, ISSN: 0952-3499. @article{karplus_dynamical_2010, title = {Dynamical aspects of molecular recognition Introduction}, author = {Karplus, Martin}, doi = {10.1002/jmr.1018}, issn = {0952-3499}, year = {2010}, date = {2010-04-01}, journal = {JOURNAL OF MOLECULAR RECOGNITION}, volume = {23}, number = {2, SI}, pages = {102--104}, keywords = {}, pubstate = {published}, tppubtype = {article} } |
Schwartz, Erik ; Lim, Eunhee ; Gowda, Chandrakala M; Liscio, Andrea ; Fenwick, Oliver ; Tu, Guoli ; Palermo, Vincenzo ; de Gelder, Rene ; Cornelissen, Jeroen J L M; Van Eck, Ernst R H; Kentgens, Arno P M; Cacialli, Franco ; Nolte, Roeland J M; Samori, Paolo ; Huck, Wilhelm T S; Rowan, Alan E Synthesis, Characterization, and Surface Initiated Polymerization of Carbazole Functionalized Isocyanides Journal Article In: CHEMISTRY OF MATERIALS, 22 (8), pp. 2597–2607, 2010, ISSN: 0897-4756. @article{schwartz_synthesis_2010, title = {Synthesis, Characterization, and Surface Initiated Polymerization of Carbazole Functionalized Isocyanides}, author = {Schwartz, Erik and Lim, Eunhee and Gowda, Chandrakala M. and Liscio, Andrea and Fenwick, Oliver and Tu, Guoli and Palermo, Vincenzo and de Gelder, Rene and Cornelissen, Jeroen J. L. M. and Van Eck, Ernst R. H. and Kentgens, Arno P. M. and Cacialli, Franco and Nolte, Roeland J. M. and Samori, Paolo and Huck, Wilhelm T. S. and Rowan, Alan E.}, doi = {10.1021/cm903664g}, issn = {0897-4756}, year = {2010}, date = {2010-04-01}, journal = {CHEMISTRY OF MATERIALS}, volume = {22}, number = {8}, pages = {2597--2607}, abstract = {We describe the design and synthesis of carbazole functionalized isocyanides and the detailed investigation of their properties. Characterization by solid state NMR, CD, and IR spectroscopic techniques reveals that the polymer has a well-defined helical architecture. Surface-initiated polymerization of the isocyanide monomers onto various surfaces was carried out to give polymer brushes up to 150 nm thick. Insights into the electronic properties of the materials were obtained by Kelvin probe force microscopy (KPFM) and electroabsorption studies}, keywords = {}, pubstate = {published}, tppubtype = {article} } We describe the design and synthesis of carbazole functionalized isocyanides and the detailed investigation of their properties. Characterization by solid state NMR, CD, and IR spectroscopic techniques reveals that the polymer has a well-defined helical architecture. Surface-initiated polymerization of the isocyanide monomers onto various surfaces was carried out to give polymer brushes up to 150 nm thick. Insights into the electronic properties of the materials were obtained by Kelvin probe force microscopy (KPFM) and electroabsorption studies |
Liscio, Andrea ; Palermo, Vincenzo ; Samori, Paolo Nanoscale Quantitative Measurement of the Potential of Charged Nanostructures by Electrostatic and Kelvin Probe Force Microscopy: Unraveling Electronic Processes in Complex Materials Journal Article In: ACCOUNTS OF CHEMICAL RESEARCH, 43 (4), pp. 541–550, 2010, ISSN: 0001-4842. @article{liscio_nanoscale_2010, title = {Nanoscale Quantitative Measurement of the Potential of Charged Nanostructures by Electrostatic and Kelvin Probe Force Microscopy: Unraveling Electronic Processes in Complex Materials}, author = {Liscio, Andrea and Palermo, Vincenzo and Samori, Paolo}, doi = {10.1021/ar900247p}, issn = {0001-4842}, year = {2010}, date = {2010-04-01}, journal = {ACCOUNTS OF CHEMICAL RESEARCH}, volume = {43}, number = {4}, pages = {541--550}, abstract = {In microelectronics and biology, many fundamental processes involve the exchange of charges between small objects, such as nanocrystals in photovoltaic blends or individual proteins in photosynthetic reactions. Because these nanoscale electronic processes strongly depend on the structure of the electroactive assemblies, a detailed understanding of these phenomena requires unraveling the relationship between the structure of the nano-object and its electronic function. Because of the fragility of the structures involved and the dynamic variance of the electric potential of each nanostructure during the charge generation and transport processes, understanding this structure function relationship represents a great challenge. This Account discusses how our group and others have exploited scanning probe microscopy based approaches beyond imaging, particularly Kelvin probe force microscopy (KPFM), to map the potential of different nanostructures with a spatial and voltage resolution of a few nanometers and millivolts, respectively. We describe in detail how these techniques can provide researchers several types of chemical information. First, KPFM allows researchers to visualize the photogeneration and splitting of several unitary charges between well-defined nanoobjects having complementary electron-acceptor and -donor properties. In addition, this method maps charge injection and transport in thin layers of polycrystalline materials. Finally, KPFM can monitor the activity of immobilized chemical components of natural photosynthetic systems. In particular, researchers can use KPFM to measure the electric potential without physical contact between the tip and the nanostructure studied. These measurements exploit long-range electrostatic interactions between the scanning probe and the sample, which scale with the square of the probe sample distance, d. While allowing minimal perturbation, these long-range interactions limit the resolution attainable in the measurement of potentials. Although the spatial resolution of KPFM is on the nanometer scale, it is inferior to that of other related techniques such as atomic force or scanning tunneling microscopy, which are based on short-range interactions scaling as d(-7) or e(-d), respectively. To overcome this problem, we have recently devised deconvolution procedures that allow us to quantify the electric potential of a nano-object removing the artifacts due to its nanometric size.}, keywords = {}, pubstate = {published}, tppubtype = {article} } In microelectronics and biology, many fundamental processes involve the exchange of charges between small objects, such as nanocrystals in photovoltaic blends or individual proteins in photosynthetic reactions. Because these nanoscale electronic processes strongly depend on the structure of the electroactive assemblies, a detailed understanding of these phenomena requires unraveling the relationship between the structure of the nano-object and its electronic function. Because of the fragility of the structures involved and the dynamic variance of the electric potential of each nanostructure during the charge generation and transport processes, understanding this structure function relationship represents a great challenge. This Account discusses how our group and others have exploited scanning probe microscopy based approaches beyond imaging, particularly Kelvin probe force microscopy (KPFM), to map the potential of different nanostructures with a spatial and voltage resolution of a few nanometers and millivolts, respectively. We describe in detail how these techniques can provide researchers several types of chemical information. First, KPFM allows researchers to visualize the photogeneration and splitting of several unitary charges between well-defined nanoobjects having complementary electron-acceptor and -donor properties. In addition, this method maps charge injection and transport in thin layers of polycrystalline materials. Finally, KPFM can monitor the activity of immobilized chemical components of natural photosynthetic systems. In particular, researchers can use KPFM to measure the electric potential without physical contact between the tip and the nanostructure studied. These measurements exploit long-range electrostatic interactions between the scanning probe and the sample, which scale with the square of the probe sample distance, d. While allowing minimal perturbation, these long-range interactions limit the resolution attainable in the measurement of potentials. Although the spatial resolution of KPFM is on the nanometer scale, it is inferior to that of other related techniques such as atomic force or scanning tunneling microscopy, which are based on short-range interactions scaling as d(-7) or e(-d), respectively. To overcome this problem, we have recently devised deconvolution procedures that allow us to quantify the electric potential of a nano-object removing the artifacts due to its nanometric size. |
Ruff, Yves ; Buhler, Eric ; Candau, Sauveur-Jean ; Kesselman, Ellina ; Talmon, Yeshayahu ; Lehn, Jean-Marie Glycodynamers: Dynamic Polymers Bearing Oligosaccharides Residues - Generation, Structure, Physicochemical, Component Exchange, and Lectin Binding Properties Journal Article In: JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, 132 (8), pp. 2573–2584, 2010, ISSN: 0002-7863. @article{ruff_glycodynamers:_2010, title = {Glycodynamers: Dynamic Polymers Bearing Oligosaccharides Residues - Generation, Structure, Physicochemical, Component Exchange, and Lectin Binding Properties}, author = {Ruff, Yves and Buhler, Eric and Candau, Sauveur-Jean and Kesselman, Ellina and Talmon, Yeshayahu and Lehn, Jean-Marie}, doi = {10.1021/ja9082733}, issn = {0002-7863}, year = {2010}, date = {2010-03-01}, journal = {JOURNAL OF THE AMERICAN CHEMICAL SOCIETY}, volume = {132}, number = {8}, pages = {2573--2584}, abstract = {Dynamic glycopolymers have been generated by polycondensation through acylhydrazone formation between components bearing lateral bioactive oligosaccharide chains. They have been characterized as bottlebrush type by cryo-TEM and SANS studies. They present remarkable fluorescence properties whose emission wavelengths depend on the constitution of the polymer and are tunable by constitutional modification through exchange/incorporation of components, thus also demonstrating their dynamic character. Constitution-dependent binding of these glycodynamers to a lectin, peanut agglutinin, has been demonstrated.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Dynamic glycopolymers have been generated by polycondensation through acylhydrazone formation between components bearing lateral bioactive oligosaccharide chains. They have been characterized as bottlebrush type by cryo-TEM and SANS studies. They present remarkable fluorescence properties whose emission wavelengths depend on the constitution of the polymer and are tunable by constitutional modification through exchange/incorporation of components, thus also demonstrating their dynamic character. Constitution-dependent binding of these glycodynamers to a lectin, peanut agglutinin, has been demonstrated. |
Beyler, Maryline ; Heitz, Valerie ; Sauvage, Jean-Pierre Coordination Chemistry-Assembled Porphyrinic Catenanes Journal Article In: JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, 132 (12), pp. 4409–4417, 2010, ISSN: 0002-7863. @article{beyler_coordination_2010, title = {Coordination Chemistry-Assembled Porphyrinic Catenanes}, author = {Beyler, Maryline and Heitz, Valerie and Sauvage, Jean-Pierre}, doi = {10.1021/ja910747h}, issn = {0002-7863}, year = {2010}, date = {2010-03-01}, journal = {JOURNAL OF THE AMERICAN CHEMICAL SOCIETY}, volume = {132}, number = {12}, pages = {4409--4417}, abstract = {Non covalent [2]catenanes were synthesized in high yield as kinetic products or as thermodynamic products after completion of an equilibrium. These sophisticated architectures were assembled in two steps, from an oblique bis-zinc(II) porphyrin and two different dipyridyl chelates, by using Cu(I)-N interactions to assemble acyclic complexes and Zn(II)-N interactions to generate rings. (1)H NMR including 2D COSY and ROESY experiments were used to characterize each compound. Spectrophotometric titrations highlight the influence of geometry in terms of distances and angles in non covalent coordinated assemblies. In fact, it was proved that a perfect fit leads to highly stable coordination chemistry-assembled species.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Non covalent [2]catenanes were synthesized in high yield as kinetic products or as thermodynamic products after completion of an equilibrium. These sophisticated architectures were assembled in two steps, from an oblique bis-zinc(II) porphyrin and two different dipyridyl chelates, by using Cu(I)-N interactions to assemble acyclic complexes and Zn(II)-N interactions to generate rings. (1)H NMR including 2D COSY and ROESY experiments were used to characterize each compound. Spectrophotometric titrations highlight the influence of geometry in terms of distances and angles in non covalent coordinated assemblies. In fact, it was proved that a perfect fit leads to highly stable coordination chemistry-assembled species. |
Sauvage, Jean-Pierre ; Collin, Jean-Paul ; Durot, Stephanie ; Frey, Julien ; Heitz, Valerie ; Sour, Angelique ; Lock, Christian From chemical topology to molecular machines Journal Article In: COMPTES RENDUS CHIMIE, 13 (3, SI), pp. 315–328, 2010, ISSN: 1631-0748. @article{sauvage_chemical_2010, title = {From chemical topology to molecular machines}, author = {Sauvage, Jean-Pierre and Collin, Jean-Paul and Durot, Stephanie and Frey, Julien and Heitz, Valerie and Sour, Angelique and Lock, Christian}, doi = {10.1016/j.crci.2009.10.008}, issn = {1631-0748}, year = {2010}, date = {2010-03-01}, journal = {COMPTES RENDUS CHIMIE}, volume = {13}, number = {3, SI}, pages = {315--328}, abstract = {The chemistry of molecules displaying novel topologies has experienced an explosive development in the course of the last 25 years. The fast growth of this field originates to a large extent from the new templated synthetic methods which allow one to prepare these compounds at a real macroscopic level. Our group, in particular, has proposed a particularly efficient copper(I)-based template synthesis of a large variety of catenanes and rotaxanes at an early stage, participating in the revival of molecular topology. One of the highlights of the field has been the synthesis of the trefoil knot, a particularly challenging target. This object is not only an aesthetically attractive molecule but it also displays interesting properties in relation to coordination chemistry and chirality. A highly promising extension of molecular topology is that of molecular machines. By combining the specific properties of catenanes and rotaxanes, i.e., marked flexibility and propensity to undergo large amplitude motions, and coordination chemistry, it has been possible to elaborate and study a large variety of molecular machines. A recent example is that of an adjustable receptor, based on a [3]rotaxane attached to two mobile porphyrinic plates. This compound and related molecules will lead to “molecular presses” and, eventually, to molecular machines usable in solution to catalyse reactions or change the conformation of given substrates. (C) 2009 Academie des sciences. Published by Elsevier Masson SAS. All rights reserved.}, keywords = {}, pubstate = {published}, tppubtype = {article} } The chemistry of molecules displaying novel topologies has experienced an explosive development in the course of the last 25 years. The fast growth of this field originates to a large extent from the new templated synthetic methods which allow one to prepare these compounds at a real macroscopic level. Our group, in particular, has proposed a particularly efficient copper(I)-based template synthesis of a large variety of catenanes and rotaxanes at an early stage, participating in the revival of molecular topology. One of the highlights of the field has been the synthesis of the trefoil knot, a particularly challenging target. This object is not only an aesthetically attractive molecule but it also displays interesting properties in relation to coordination chemistry and chirality. A highly promising extension of molecular topology is that of molecular machines. By combining the specific properties of catenanes and rotaxanes, i.e., marked flexibility and propensity to undergo large amplitude motions, and coordination chemistry, it has been possible to elaborate and study a large variety of molecular machines. A recent example is that of an adjustable receptor, based on a [3]rotaxane attached to two mobile porphyrinic plates. This compound and related molecules will lead to “molecular presses” and, eventually, to molecular machines usable in solution to catalyse reactions or change the conformation of given substrates. (C) 2009 Academie des sciences. Published by Elsevier Masson SAS. All rights reserved. |
Garcia-Vidal, F J; Martin-Moreno, L; Ebbesen, T W; Kuipers, L Light passing through subwavelength apertures Journal Article In: REVIEWS OF MODERN PHYSICS, 82 (1), pp. 729–787, 2010, ISSN: 0034-6861. @article{garcia-vidal_light_2010, title = {Light passing through subwavelength apertures}, author = {Garcia-Vidal, F. J. and Martin-Moreno, L. and Ebbesen, T. W. and Kuipers, L.}, doi = {10.1103/RevModPhys.82.729}, issn = {0034-6861}, year = {2010}, date = {2010-03-01}, journal = {REVIEWS OF MODERN PHYSICS}, volume = {82}, number = {1}, pages = {729--787}, abstract = {This review provides a perspective on the recent developments in the transmission of light through subwavelength apertures in metal films. The main focus is on the phenomenon of extraordinary optical transmission in periodic hole arrays, discovered over a decade ago. It is shown that surface electromagnetic modes play a key role in the emergence of the resonant transmission. These modes are also shown to be at the root of both the enhanced transmission and beaming of light found in single apertures surrounded by periodic corrugations. This review describes both the theoretical and experimental aspects of the subject. For clarity, the physical mechanisms operating in the different structures considered are analyzed within a common theoretical framework. Several applications based on the transmission properties of subwavelength apertures are also addressed.}, keywords = {}, pubstate = {published}, tppubtype = {article} } This review provides a perspective on the recent developments in the transmission of light through subwavelength apertures in metal films. The main focus is on the phenomenon of extraordinary optical transmission in periodic hole arrays, discovered over a decade ago. It is shown that surface electromagnetic modes play a key role in the emergence of the resonant transmission. These modes are also shown to be at the root of both the enhanced transmission and beaming of light found in single apertures surrounded by periodic corrugations. This review describes both the theoretical and experimental aspects of the subject. For clarity, the physical mechanisms operating in the different structures considered are analyzed within a common theoretical framework. Several applications based on the transmission properties of subwavelength apertures are also addressed. |
Grinthal, Alison ; Adamovic, Ivana ; Weiner, Beth ; Karplus, Martin ; Kleckner, Nancy PR65, the HEAT-repeat scaffold of phosphatase PP2A, is an elastic connector that links force and catalysis Journal Article In: PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA, 107 (6), pp. 2467–2472, 2010, ISSN: 0027-8424. @article{grinthal_pr65_2010, title = {PR65, the HEAT-repeat scaffold of phosphatase PP2A, is an elastic connector that links force and catalysis}, author = {Grinthal, Alison and Adamovic, Ivana and Weiner, Beth and Karplus, Martin and Kleckner, Nancy}, doi = {10.1073/pnas.0914073107}, issn = {0027-8424}, year = {2010}, date = {2010-02-01}, journal = {PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA}, volume = {107}, number = {6}, pages = {2467--2472}, abstract = {PR65 is the two-layered (alpha-alpha solenoid) HEAT-repeat (Huntingtin, elongation factor 3, a subunit of protein phosphatase 2A, PI3 kinase target of rapamycin 1) scaffold of protein phosphatase PP2A. Molecular dynamics simulations predict that, at forces expected in living systems, PR65 undergoes (visco-)elastic deformations in response to pulling/pushing on its ends. At lower forces, smooth global flexural and torsional changes occur via even redistribution of stress along the hydrophobic core of the molecule. At intermediate forces, helix-helix separation along one layer (”fracturing”) leads to global relaxation plus loss of contact in the other layer to unstack the affected units. Fracture sites are determined by unusual sequences in contiguous interhelix turns. Normal mode analysis of the heterotrimeric PP2A enzyme reveals that its ambient conformational fluctuations are dominated by elastic deformations of PR65, which introduce a mechanical linkage between the separately bound regulatory and catalytic subunits. PR65-dominated fluctuations of PP2A have the effect of opening and closing the enzyme's substrate binding/catalysis interface, as well as altering the positions of certain catalytic residues. These results suggest that substrate binding/catalysis are sensitive to mechanical force. Force could be imposed from the outside (e.g., in PP2A's response to spindle tension) or arise spontaneously (e.g., in PP2A's interaction with unstructured proteins such as Tau, a microtubule-associated Alzheimer's-implicated protein). The presented example supports the view that conformation and function of protein complexes can be modulated by mechanical energy inputs, as well as by chemical energy inputs from ligand binding. Given that helical-repeat proteins are involved in many cellular processes, the findings also encourage the view that mechanical forces may be of widespread importance.}, keywords = {}, pubstate = {published}, tppubtype = {article} } PR65 is the two-layered (alpha-alpha solenoid) HEAT-repeat (Huntingtin, elongation factor 3, a subunit of protein phosphatase 2A, PI3 kinase target of rapamycin 1) scaffold of protein phosphatase PP2A. Molecular dynamics simulations predict that, at forces expected in living systems, PR65 undergoes (visco-)elastic deformations in response to pulling/pushing on its ends. At lower forces, smooth global flexural and torsional changes occur via even redistribution of stress along the hydrophobic core of the molecule. At intermediate forces, helix-helix separation along one layer (”fracturing”) leads to global relaxation plus loss of contact in the other layer to unstack the affected units. Fracture sites are determined by unusual sequences in contiguous interhelix turns. Normal mode analysis of the heterotrimeric PP2A enzyme reveals that its ambient conformational fluctuations are dominated by elastic deformations of PR65, which introduce a mechanical linkage between the separately bound regulatory and catalytic subunits. PR65-dominated fluctuations of PP2A have the effect of opening and closing the enzyme's substrate binding/catalysis interface, as well as altering the positions of certain catalytic residues. These results suggest that substrate binding/catalysis are sensitive to mechanical force. Force could be imposed from the outside (e.g., in PP2A's response to spindle tension) or arise spontaneously (e.g., in PP2A's interaction with unstructured proteins such as Tau, a microtubule-associated Alzheimer's-implicated protein). The presented example supports the view that conformation and function of protein complexes can be modulated by mechanical energy inputs, as well as by chemical energy inputs from ligand binding. Given that helical-repeat proteins are involved in many cellular processes, the findings also encourage the view that mechanical forces may be of widespread importance. |
Palermo, Vincenzo ; Schwartz, Erik ; Finlayson, Chris E; Liscio, Andrea ; Otten, Matthijs B J; Trapani, Sara ; Muellen, Klaus ; Beljonne, David ; Friend, Richard H; Nolte, Roelond J M; Rowan, Alan E; Samori, Paolo Macromolecular Scaffolding: The Relationship Between Nanoscale Architecture and Function in Multichromophoric Arrays for Organic Electronics Journal Article In: ADVANCED MATERIALS, 22 (8), pp. E81+, 2010, ISSN: 0935-9648. @article{palermo_macromolecular_2010, title = {Macromolecular Scaffolding: The Relationship Between Nanoscale Architecture and Function in Multichromophoric Arrays for Organic Electronics}, author = {Palermo, Vincenzo and Schwartz, Erik and Finlayson, Chris E. and Liscio, Andrea and Otten, Matthijs B. J. and Trapani, Sara and Muellen, Klaus and Beljonne, David and Friend, Richard H. and Nolte, Roelond J. M. and Rowan, Alan E. and Samori, Paolo}, doi = {10.1002/adma.200903672}, issn = {0935-9648}, year = {2010}, date = {2010-02-01}, journal = {ADVANCED MATERIALS}, volume = {22}, number = {8}, pages = {E81+}, abstract = {The optimization of the electronic properties of molecular materials based on optically or electrically active organic building blocks requires a fine-tuning of their self-assembly properties at surfaces. Such a fine-tuning can be obtained on a scale up to 10 nm by mastering principles of supramolecular chemistry, i.e., by using suitably designed molecules interacting via pre-programmed noncovalent forces. The control and fine-tuning on a greater length scale is more difficult and challenging. This Research News highlights recent results we obtained on a new class of macromolecules that possess a very rigid backbone and side chains that point away from this backbone. Each side chain contains an organic semiconducting moiety, whose position and electronic interaction with neighboring moieties are dictated by the central macromolecular scaffold. A combined experimental and theoretical approach has made it possible to unravel the physical and chemical properties of this system across multiple length scales. The (opto)electronic properties of the new functional architectures have been explored by constructing prototypes of field-effect transistors and solar cells, thereby providing direct insight into the relationship between architecture and function.}, keywords = {}, pubstate = {published}, tppubtype = {article} } The optimization of the electronic properties of molecular materials based on optically or electrically active organic building blocks requires a fine-tuning of their self-assembly properties at surfaces. Such a fine-tuning can be obtained on a scale up to 10 nm by mastering principles of supramolecular chemistry, i.e., by using suitably designed molecules interacting via pre-programmed noncovalent forces. The control and fine-tuning on a greater length scale is more difficult and challenging. This Research News highlights recent results we obtained on a new class of macromolecules that possess a very rigid backbone and side chains that point away from this backbone. Each side chain contains an organic semiconducting moiety, whose position and electronic interaction with neighboring moieties are dictated by the central macromolecular scaffold. A combined experimental and theoretical approach has made it possible to unravel the physical and chemical properties of this system across multiple length scales. The (opto)electronic properties of the new functional architectures have been explored by constructing prototypes of field-effect transistors and solar cells, thereby providing direct insight into the relationship between architecture and function. |
Lombard, E; Drezet, A; Genet, C; Ebbesen, T W Polarization control of non-diffractive helical optical beams through subwavelength metallic apertures Journal Article In: NEW JOURNAL OF PHYSICS, 12 , 2010, ISSN: 1367-2630. @article{lombard_polarization_2010, title = {Polarization control of non-diffractive helical optical beams through subwavelength metallic apertures}, author = {Lombard, E. and Drezet, A. and Genet, C. and Ebbesen, T. W.}, doi = {10.1088/1367-2630/12/2/023027}, issn = {1367-2630}, year = {2010}, date = {2010-02-01}, journal = {NEW JOURNAL OF PHYSICS}, volume = {12}, abstract = {We demonstrate experimentally a simple method for preparing non-diffractive vectorial optical beams that can display wave-front helicity. This method is based on space-variant modifications of the polarization of an optical beam transmitted through subwavelength annular rings perforating opaque metal films. We show how the description of the optical properties of such structures must account for the vectorial character of the polarization and how, in turn, these properties can be controlled by straightforward sequences of preparation and analysis of polarization states.}, keywords = {}, pubstate = {published}, tppubtype = {article} } We demonstrate experimentally a simple method for preparing non-diffractive vectorial optical beams that can display wave-front helicity. This method is based on space-variant modifications of the polarization of an optical beam transmitted through subwavelength annular rings perforating opaque metal films. We show how the description of the optical properties of such structures must account for the vectorial character of the polarization and how, in turn, these properties can be controlled by straightforward sequences of preparation and analysis of polarization states. |
Ovchinnikov, Victor ; Trout, Bernhardt L; Karplus, Martin Mechanical Coupling in Myosin V: A Simulation Study Journal Article In: JOURNAL OF MOLECULAR BIOLOGY, 395 (4), pp. 815–833, 2010, ISSN: 0022-2836. @article{ovchinnikov_mechanical_2010, title = {Mechanical Coupling in Myosin V: A Simulation Study}, author = {Ovchinnikov, Victor and Trout, Bernhardt L. and Karplus, Martin}, doi = {10.1016/j.jmb.2009.10.029}, issn = {0022-2836}, year = {2010}, date = {2010-01-01}, journal = {JOURNAL OF MOLECULAR BIOLOGY}, volume = {395}, number = {4}, pages = {815--833}, abstract = {Myosin motor function depends on the interaction between different domains that transmit information from one part of the molecule to another. The interdomain coupling in myosin V is studied with restrained targeted molecular dynamics using an all-atom representation in explicit solvent. To elucidate the origin of the conformational change due to the binding of ATP, targeting forces are applied to small sets of atoms (the forcing sets, FSs) in the direction of their displacement from the rigor conformation, which has a closed actin-binding cleft, to the post-rigor conformation, in which the cleft is open. The “minimal” FS that results in extensive structural changes in the overall myosin conformation is composed of ATP, switch 1, and the nearby HF, HG, and HH helices. Addition of switch 2 to the FS is required to achieve a complete opening of the actin-binding cleft. The restrained targeted molecular dynamics simulations reveal the mechanical coupling pathways between (i) the nucleotide-binding pocket (NBP) and the actin-binding cleft, (ii) the NBP and the converter, and (iii) the actin-binding cleft and the converter. Closing of the NBP due to ATP binding is tightly coupled to the opening of the cleft and leads to the rupture of a key hydrogen bond (F441N/A684O) between switch 2 and the SH1 helix. The actin-binding cleft may mediate the rupture of this bond via a connection between the HW helix, the relay helix, and switch 2. The findings are consistent with experimental studies and a recent normal mode analysis. The present method is expected to be useful more generally in studies of interdomain coupling in proteins. (C) 2009 Elsevier Ltd. All rights reserved.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Myosin motor function depends on the interaction between different domains that transmit information from one part of the molecule to another. The interdomain coupling in myosin V is studied with restrained targeted molecular dynamics using an all-atom representation in explicit solvent. To elucidate the origin of the conformational change due to the binding of ATP, targeting forces are applied to small sets of atoms (the forcing sets, FSs) in the direction of their displacement from the rigor conformation, which has a closed actin-binding cleft, to the post-rigor conformation, in which the cleft is open. The “minimal” FS that results in extensive structural changes in the overall myosin conformation is composed of ATP, switch 1, and the nearby HF, HG, and HH helices. Addition of switch 2 to the FS is required to achieve a complete opening of the actin-binding cleft. The restrained targeted molecular dynamics simulations reveal the mechanical coupling pathways between (i) the nucleotide-binding pocket (NBP) and the actin-binding cleft, (ii) the NBP and the converter, and (iii) the actin-binding cleft and the converter. Closing of the NBP due to ATP binding is tightly coupled to the opening of the cleft and leads to the rupture of a key hydrogen bond (F441N/A684O) between switch 2 and the SH1 helix. The actin-binding cleft may mediate the rupture of this bond via a connection between the HW helix, the relay helix, and switch 2. The findings are consistent with experimental studies and a recent normal mode analysis. The present method is expected to be useful more generally in studies of interdomain coupling in proteins. (C) 2009 Elsevier Ltd. All rights reserved. |
Golosov, Andrei A; Warren, Joshua J; Beese, Lorena S; Karplus, Martin The Mechanism of the Translocation Step in DNA Replication by DNA Polymerase I: A Computer Simulation Analysis Journal Article In: STRUCTURE, 18 (1), pp. 83–93, 2010, ISSN: 0969-2126. @article{golosov_mechanism_2010, title = {The Mechanism of the Translocation Step in DNA Replication by DNA Polymerase I: A Computer Simulation Analysis}, author = {Golosov, Andrei A. and Warren, Joshua J. and Beese, Lorena S. and Karplus, Martin}, doi = {10.1016/j.str.2009.10.014}, issn = {0969-2126}, year = {2010}, date = {2010-01-01}, journal = {STRUCTURE}, volume = {18}, number = {1}, pages = {83--93}, abstract = {High-fidelity DNA polymerases copy DNA rapidly and accurately by adding correct deoxynucleotide triphosphates to a growing primer strand of DNA. Following nucleotide incorporation, a series of conformational changes translocate the DNA substrate by one base pair step, readying the polymerase for the next round of incorporation. Molecular dynamics simulations indicate that the translocation consists globally of a polymerase fingers-opening transition, followed by the DNA displacement and the insertion of the template base into the preinsertion site. They also show that the pyrophosphate release facilitates the opening transition and that the universally conserved Y714 plays a key role in coupling polymerase opening to DNA translocation. The transition involves several metastable intermediates in one of which the O helix is bent in the vicinity of G711. Completion of the translocation appears to require a gating motion of the O1 helix, perhaps facilitated by the presence of G715. These roles are consistent with the high level of conservation of Y714 and the two glycine residues at these positions. It is likely that a corresponding mechanism is applicable to other polymerases.}, keywords = {}, pubstate = {published}, tppubtype = {article} } High-fidelity DNA polymerases copy DNA rapidly and accurately by adding correct deoxynucleotide triphosphates to a growing primer strand of DNA. Following nucleotide incorporation, a series of conformational changes translocate the DNA substrate by one base pair step, readying the polymerase for the next round of incorporation. Molecular dynamics simulations indicate that the translocation consists globally of a polymerase fingers-opening transition, followed by the DNA displacement and the insertion of the template base into the preinsertion site. They also show that the pyrophosphate release facilitates the opening transition and that the universally conserved Y714 plays a key role in coupling polymerase opening to DNA translocation. The transition involves several metastable intermediates in one of which the O helix is bent in the vicinity of G711. Completion of the translocation appears to require a gating motion of the O1 helix, perhaps facilitated by the presence of G715. These roles are consistent with the high level of conservation of Y714 and the two glycine residues at these positions. It is likely that a corresponding mechanism is applicable to other polymerases. |
Qi, Yan ; Spong, Marie C; Nam, Kwangho ; Karplus, Martin ; Verdine, Gregory L Entrapment and Structure of an Extrahelical Guanine Attempting to Enter the Active Site of a Bacterial DNA Glycosylase, MutM Journal Article In: JOURNAL OF BIOLOGICAL CHEMISTRY, 285 (2), pp. 1468–1478, 2010, ISSN: 0021-9258. @article{qi_entrapment_2010, title = {Entrapment and Structure of an Extrahelical Guanine Attempting to Enter the Active Site of a Bacterial DNA Glycosylase, MutM}, author = {Qi, Yan and Spong, Marie C. and Nam, Kwangho and Karplus, Martin and Verdine, Gregory L.}, doi = {10.1074/jbc.M109.069799}, issn = {0021-9258}, year = {2010}, date = {2010-01-01}, journal = {JOURNAL OF BIOLOGICAL CHEMISTRY}, volume = {285}, number = {2}, pages = {1468--1478}, abstract = {MutM, a bacterial DNA glycosylase, protects genome integrity by catalyzing glycosidic bond cleavage of 8-oxoguanine (oxoG) lesions, thereby initiating base excision DNA repair. The process of searching for and locating oxoG lesions is especially challenging, because of the close structural resemblance of oxoG to its million-fold more abundant progenitor, G. Extrusion of the target nucleobase from the DNA double helix to an extrahelical position is an essential step in lesion recognition and catalysis by MutM. Although the interactions between the extruded oxoG and the active site of MutM have been well characterized, little is known in structural detail regarding the interrogation of extruded normal DNA bases by MutM. Here we report the capture and structural elucidation of a complex in which MutM is attempting to present an undamaged G to its active site. The structure of this MutM-extrahelical G complex provides insights into the mechanism MutM employs to discriminate against extrahelical normal DNA bases and into the base extrusion process in general.}, keywords = {}, pubstate = {published}, tppubtype = {article} } MutM, a bacterial DNA glycosylase, protects genome integrity by catalyzing glycosidic bond cleavage of 8-oxoguanine (oxoG) lesions, thereby initiating base excision DNA repair. The process of searching for and locating oxoG lesions is especially challenging, because of the close structural resemblance of oxoG to its million-fold more abundant progenitor, G. Extrusion of the target nucleobase from the DNA double helix to an extrahelical position is an essential step in lesion recognition and catalysis by MutM. Although the interactions between the extruded oxoG and the active site of MutM have been well characterized, little is known in structural detail regarding the interrogation of extruded normal DNA bases by MutM. Here we report the capture and structural elucidation of a complex in which MutM is attempting to present an undamaged G to its active site. The structure of this MutM-extrahelical G complex provides insights into the mechanism MutM employs to discriminate against extrahelical normal DNA bases and into the base extrusion process in general. |
Ciesielski, Artur ; Lena, Stefano ; Masiero, Stefano ; Spada, Gian Piero ; Samori, Paolo Dynamers at the Solid-Liquid Interface: Controlling the Reversible Assembly/Reassembly Process between Two Highly Ordered Supramolecular Guanine Motifs Journal Article In: ANGEWANDTE CHEMIE-INTERNATIONAL EDITION, 49 (11), pp. 1963–1966, 2010, ISSN: 1433-7851. @article{ciesielski_dynamers_2010, title = {Dynamers at the Solid-Liquid Interface: Controlling the Reversible Assembly/Reassembly Process between Two Highly Ordered Supramolecular Guanine Motifs}, author = {Ciesielski, Artur and Lena, Stefano and Masiero, Stefano and Spada, Gian Piero and Samori, Paolo}, doi = {10.1002/anie.200905827}, issn = {1433-7851}, year = {2010}, date = {2010-01-01}, journal = {ANGEWANDTE CHEMIE-INTERNATIONAL EDITION}, volume = {49}, number = {11}, pages = {1963--1966}, keywords = {}, pubstate = {published}, tppubtype = {article} } |
Raimondo, Corinna ; Reinders, Federica ; Soydaner, Umut ; Mayor, Marcel ; Samori, Paolo Light-responsive reversible solvation and precipitation of gold nanoparticles Journal Article In: CHEMICAL COMMUNICATIONS, 46 (7), pp. 1147–1149, 2010, ISSN: 1359-7345. @article{raimondo_light-responsive_2010, title = {Light-responsive reversible solvation and precipitation of gold nanoparticles}, author = {Raimondo, Corinna and Reinders, Federica and Soydaner, Umut and Mayor, Marcel and Samori, Paolo}, doi = {10.1039/b915491d}, issn = {1359-7345}, year = {2010}, date = {2010-01-01}, journal = {CHEMICAL COMMUNICATIONS}, volume = {46}, number = {7}, pages = {1147--1149}, abstract = {Photo-irradiation with visible and UV light can be used to reversibly trigger the precipitation and solvation, in organic media, of Au nanoparticles coated with a rigid-rod type azobenzene.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Photo-irradiation with visible and UV light can be used to reversibly trigger the precipitation and solvation, in organic media, of Au nanoparticles coated with a rigid-rod type azobenzene. |
Samori, Cristian ; Ali-Boucetta, Hanene ; Sainz, Raquel ; Guo, Chang ; Toma, Francesca Maria ; Fabbro, Chiara ; da Ros, Tatiana ; Prato, Maurizio ; Kostarelos, Kostas ; Bianco, Alberto Enhanced anticancer activity of multi-walled carbon nanotube-methotrexate conjugates using cleavable linkers Journal Article In: CHEMICAL COMMUNICATIONS, 46 (9), pp. 1494–1496, 2010, ISSN: 1359-7345. @article{samori_enhanced_2010, title = {Enhanced anticancer activity of multi-walled carbon nanotube-methotrexate conjugates using cleavable linkers}, author = {Samori, Cristian and Ali-Boucetta, Hanene and Sainz, Raquel and Guo, Chang and Toma, Francesca Maria and Fabbro, Chiara and da Ros, Tatiana and Prato, Maurizio and Kostarelos, Kostas and Bianco, Alberto}, doi = {10.1039/b923560d}, issn = {1359-7345}, year = {2010}, date = {2010-01-01}, journal = {CHEMICAL COMMUNICATIONS}, volume = {46}, number = {9}, pages = {1494--1496}, abstract = {Methotrexate was tethered to multi-walled carbon nanotubes through different cleavable linkers exploiting the ammonium functionalities introduced by 1,3-dipolar cycloaddition reaction of azomethine ylides to the nanotubes. The new nanobio-hybrid conjugates were internalized into human breast cancer cells and it was shown that the cytotoxic activity was strongly dependent on the presence and type of linker.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Methotrexate was tethered to multi-walled carbon nanotubes through different cleavable linkers exploiting the ammonium functionalities introduced by 1,3-dipolar cycloaddition reaction of azomethine ylides to the nanotubes. The new nanobio-hybrid conjugates were internalized into human breast cancer cells and it was shown that the cytotoxic activity was strongly dependent on the presence and type of linker. |
Ciesielski, Artur ; Perone, Rosaria ; Pieraccini, Silvia ; Spada, Gian Piero ; Samori, Paolo Nanopatterning the surface with ordered supramolecular architectures of N-9-alkylated guanines: STM reveals Journal Article In: CHEMICAL COMMUNICATIONS, 46 (25), pp. 4493–4495, 2010, ISSN: 1359-7345. @article{ciesielski_nanopatterning_2010, title = {Nanopatterning the surface with ordered supramolecular architectures of N-9-alkylated guanines: STM reveals}, author = {Ciesielski, Artur and Perone, Rosaria and Pieraccini, Silvia and Spada, Gian Piero and Samori, Paolo}, doi = {10.1039/c0cc00443j}, issn = {1359-7345}, year = {2010}, date = {2010-01-01}, journal = {CHEMICAL COMMUNICATIONS}, volume = {46}, number = {25}, pages = {4493--4495}, abstract = {STM study of the self-assembly at the solid-liquid interface of substituted guanines exposing in the N-9-position alkyl side chains with different lengths revealed the formation of distinct crystalline nanopatterns.}, keywords = {}, pubstate = {published}, tppubtype = {article} } STM study of the self-assembly at the solid-liquid interface of substituted guanines exposing in the N-9-position alkyl side chains with different lengths revealed the formation of distinct crystalline nanopatterns. |
Zalewski, Leszek ; Wykes, Michael ; Brovelli, Sergio ; Bonini, Massimo ; Breiner, Thomas ; Kastler, Marcel ; Doetz, Florian ; Beljonne, David ; Anderson, Harry L; Cacialli, Franco ; Samori, Paolo A Conjugated Thiophene-Based Rotaxane: Synthesis, Spectroscopy, and Modeling Journal Article In: CHEMISTRY-A EUROPEAN JOURNAL, 16 (13), pp. 3933–3941, 2010, ISSN: 0947-6539. @article{zalewski_conjugated_2010, title = {A Conjugated Thiophene-Based Rotaxane: Synthesis, Spectroscopy, and Modeling}, author = {Zalewski, Leszek and Wykes, Michael and Brovelli, Sergio and Bonini, Massimo and Breiner, Thomas and Kastler, Marcel and Doetz, Florian and Beljonne, David and Anderson, Harry L. and Cacialli, Franco and Samori, Paolo}, doi = {10.1002/chem.200903353}, issn = {0947-6539}, year = {2010}, date = {2010-01-01}, journal = {CHEMISTRY-A EUROPEAN JOURNAL}, volume = {16}, number = {13}, pages = {3933--3941}, abstract = {A dithiophene rotaxane 1 subset of beta-CD and its shape-persistent corresponding dumbbell 1 were synthesized and fully characterized. 2D NOESY experiments, supported by molecular dynamics calculations, revealed a very mobile macrocycle (beta-CD). Steady-state and time-resolved photoluminescence experiments in solution were employed to elucidate the excited-state dynamics for both systems and to explore the effect of cyclodextrin encapsulation. The photoluminescence (PL) spectrum of 1 subset of beta-CD was found to be blueshifted with respect to the dumb-bell 1 (2.81 and 2.78 eV, respectively). Additionally, in contrast to previous observations, neither PL spectra nor the decay kinetics of both threaded and unthreaded systems showed changes upon increasing the concentration or changing the polarity of the solutions, thereby providing evidence for a lack of tendency toward aggregation of the unthreaded backbone.}, keywords = {}, pubstate = {published}, tppubtype = {article} } A dithiophene rotaxane 1 subset of beta-CD and its shape-persistent corresponding dumbbell 1 were synthesized and fully characterized. 2D NOESY experiments, supported by molecular dynamics calculations, revealed a very mobile macrocycle (beta-CD). Steady-state and time-resolved photoluminescence experiments in solution were employed to elucidate the excited-state dynamics for both systems and to explore the effect of cyclodextrin encapsulation. The photoluminescence (PL) spectrum of 1 subset of beta-CD was found to be blueshifted with respect to the dumb-bell 1 (2.81 and 2.78 eV, respectively). Additionally, in contrast to previous observations, neither PL spectra nor the decay kinetics of both threaded and unthreaded systems showed changes upon increasing the concentration or changing the polarity of the solutions, thereby providing evidence for a lack of tendency toward aggregation of the unthreaded backbone. |
Bleger, David ; Ciesielski, Artur ; Samori, Paolo ; Hecht, Stefan Photoswitching Vertically Oriented Azobenzene Self-Assembled Mono layers at the Solid-Liquid Interface Journal Article In: CHEMISTRY-A EUROPEAN JOURNAL, 16 (48), pp. 14256–14260, 2010, ISSN: 0947-6539. @article{bleger_photoswitching_2010, title = {Photoswitching Vertically Oriented Azobenzene Self-Assembled Mono layers at the Solid-Liquid Interface}, author = {Bleger, David and Ciesielski, Artur and Samori, Paolo and Hecht, Stefan}, doi = {10.1002/chem.201002834}, issn = {0947-6539}, year = {2010}, date = {2010-01-01}, journal = {CHEMISTRY-A EUROPEAN JOURNAL}, volume = {16}, number = {48}, pages = {14256--14260}, keywords = {}, pubstate = {published}, tppubtype = {article} } |
De Luca, Giovanna ; Liscio, Andrea ; Melucci, Manuela ; Schnitzler, Tobias ; Pisula, Wojciech ; Clark Jr., Christopher G; Scolaro, Luigi Monsu ; Palermo, Vincenzo ; Muellen, Klaus ; Samori, Paolo Phase separation and affinity between a fluorinated perylene diimide dye and an alkyl-substituted hexa-peri-hexabenzocoronene Journal Article In: JOURNAL OF MATERIALS CHEMISTRY, 20 (1), pp. 71–82, 2010, ISSN: 0959-9428. @article{de_luca_phase_2010, title = {Phase separation and affinity between a fluorinated perylene diimide dye and an alkyl-substituted hexa-peri-hexabenzocoronene}, author = {De Luca, Giovanna and Liscio, Andrea and Melucci, Manuela and Schnitzler, Tobias and Pisula, Wojciech and Clark, Jr., Christopher G. and Scolaro, Luigi Monsu and Palermo, Vincenzo and Muellen, Klaus and Samori, Paolo}, doi = {10.1039/b915484a}, issn = {0959-9428}, year = {2010}, date = {2010-01-01}, journal = {JOURNAL OF MATERIALS CHEMISTRY}, volume = {20}, number = {1}, pages = {71--82}, abstract = {Fluorination of alkyl groups is a known strategy for hindering miscibility, thus promoting phase separation, when blends are prepared with a hydrocarbon compound. A new perylene bis(dicarboximide) derivative functionalized with branched N-perfluoroalkyl moieties (BPF-PDI) has been synthesized as electron acceptor to be potentially used in conjunction with the electron donor hexakis(dodecyl) hexabenzocoronene (HBC-C(12)) in bulk heterojunction solar cells. Aiming at controlling self-assembly between the two components at the supramolecular level, stoichiometric blends in CHCl(3) have been prepared either by spin-or drop-casting onto silicon surfaces, and further subjected to solvent vapour annealing (SVA) treatment in a CHCl(3)-saturated atmosphere. Spectroscopic investigation in solution shows the formation of supramolecular BPF-PDI-HBC-C(12) dimers, with an association constant K(ass) = (2.1 +/- 0.3) x 10(4) M(-1), pointing to a strong and unexpected affinity between the two species within the mixture. Characterization through optical and atomic force microscopies of the deposited samples revealed that the self-assembly behaviour of the blends on SiO(x) is remarkably different from mono-component films, thus confirming the absence of a macroscopic phase-separation between the two components featuring isolated domains of the neat acceptor or donor compound. In addition, X-ray studies provided evidence for the existence of a local-scale phase separation. These findings are of importance for organic photovoltaics, since they offer a new strategy to control the phase separation at different scales in electron acceptor-donor blends.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Fluorination of alkyl groups is a known strategy for hindering miscibility, thus promoting phase separation, when blends are prepared with a hydrocarbon compound. A new perylene bis(dicarboximide) derivative functionalized with branched N-perfluoroalkyl moieties (BPF-PDI) has been synthesized as electron acceptor to be potentially used in conjunction with the electron donor hexakis(dodecyl) hexabenzocoronene (HBC-C(12)) in bulk heterojunction solar cells. Aiming at controlling self-assembly between the two components at the supramolecular level, stoichiometric blends in CHCl(3) have been prepared either by spin-or drop-casting onto silicon surfaces, and further subjected to solvent vapour annealing (SVA) treatment in a CHCl(3)-saturated atmosphere. Spectroscopic investigation in solution shows the formation of supramolecular BPF-PDI-HBC-C(12) dimers, with an association constant K(ass) = (2.1 +/- 0.3) x 10(4) M(-1), pointing to a strong and unexpected affinity between the two species within the mixture. Characterization through optical and atomic force microscopies of the deposited samples revealed that the self-assembly behaviour of the blends on SiO(x) is remarkably different from mono-component films, thus confirming the absence of a macroscopic phase-separation between the two components featuring isolated domains of the neat acceptor or donor compound. In addition, X-ray studies provided evidence for the existence of a local-scale phase separation. These findings are of importance for organic photovoltaics, since they offer a new strategy to control the phase separation at different scales in electron acceptor-donor blends. |
De Luca, Giovanna ; Treossi, Emanuele ; Liscio, Andrea ; Mativetsky, Jeffrey M; Scolaro, Luigi Monsu ; Palermo, Vincenzo ; Samori, Paolo Solvent vapour annealing of organic thin films: controlling the self-assembly of functional systems across multiple length scales Journal Article In: JOURNAL OF MATERIALS CHEMISTRY, 20 (13), pp. 2493–2498, 2010, ISSN: 0959-9428. @article{de_luca_solvent_2010, title = {Solvent vapour annealing of organic thin films: controlling the self-assembly of functional systems across multiple length scales}, author = {De Luca, Giovanna and Treossi, Emanuele and Liscio, Andrea and Mativetsky, Jeffrey M. and Scolaro, Luigi Monsu and Palermo, Vincenzo and Samori, Paolo}, doi = {10.1039/b921612j}, issn = {0959-9428}, year = {2010}, date = {2010-01-01}, journal = {JOURNAL OF MATERIALS CHEMISTRY}, volume = {20}, number = {13}, pages = {2493--2498}, keywords = {}, pubstate = {published}, tppubtype = {article} } |
Treier, Matthias ; Orgiu, Emanuele ; Zalewski, Leszek ; Cho, Don ; Rieger, Ralph ; Muellen, Klaus ; Samori, Paolo Solid-solid transfer of organic semiconductors for field-effect transistor fabrication Journal Article In: JOURNAL OF MATERIALS CHEMISTRY, 20 (41), pp. 9018–9021, 2010, ISSN: 0959-9428. @article{treier_solid-solid_2010, title = {Solid-solid transfer of organic semiconductors for field-effect transistor fabrication}, author = {Treier, Matthias and Orgiu, Emanuele and Zalewski, Leszek and Cho, Don and Rieger, Ralph and Muellen, Klaus and Samori, Paolo}, doi = {10.1039/c0jm02173c}, issn = {0959-9428}, year = {2010}, date = {2010-01-01}, journal = {JOURNAL OF MATERIALS CHEMISTRY}, volume = {20}, number = {41}, pages = {9018--9021}, abstract = {We present a simple yet potentially universally applicable method for the solid-solid transfer of organic materials under ambient conditions for the fabrication of organic field-effect transistors. Thermal annealing of sprinkled powders of organic semiconductors on gold patterned SiOx surfaces yielded functional transistors with some of the characteristics comparable to those of solution-processed devices.}, keywords = {}, pubstate = {published}, tppubtype = {article} } We present a simple yet potentially universally applicable method for the solid-solid transfer of organic materials under ambient conditions for the fabrication of organic field-effect transistors. Thermal annealing of sprinkled powders of organic semiconductors on gold patterned SiOx surfaces yielded functional transistors with some of the characteristics comparable to those of solution-processed devices. |
Melucci, Manuela ; Treossi, Emanuele ; Ortolani, Luca ; Giambastiani, Giuliano ; Morandi, Vittorio ; Klar, Philipp ; Casiraghi, Cinzia ; Samori, Paolo ; Palermo, Vincenzo Facile covalent functionalization of graphene oxide using microwaves: bottom-up development of functional graphitic materials Journal Article In: JOURNAL OF MATERIALS CHEMISTRY, 20 (41), pp. 9052–9060, 2010, ISSN: 0959-9428. @article{melucci_facile_2010, title = {Facile covalent functionalization of graphene oxide using microwaves: bottom-up development of functional graphitic materials}, author = {Melucci, Manuela and Treossi, Emanuele and Ortolani, Luca and Giambastiani, Giuliano and Morandi, Vittorio and Klar, Philipp and Casiraghi, Cinzia and Samori, Paolo and Palermo, Vincenzo}, doi = {10.1039/c0jm01242d}, issn = {0959-9428}, year = {2010}, date = {2010-01-01}, journal = {JOURNAL OF MATERIALS CHEMISTRY}, volume = {20}, number = {41}, pages = {9052--9060}, abstract = {Graphene oxide (GO) exfoliated sheets were used as two dimensional platforms to covalently tether on their surface thousands of optically active quaterthiophene molecules (T4), using an innovative microwave-assisted silanization reaction. This method allowed to perform GO functionalization in one-step, under mild conditions in a few tens of minutes rather than days. The hybrid GOT4 could be processed in either H2O or apolar organic solvents and deposited as single sheets, microplatelets or macroscopic membranes. Absorption/emission spectroscopy reveals that GOT4 combines limited T4-T4 interactions with strong T4-GO ones. These findings, combined with the `user-friendly' engineering approach presented here, pave the way towards the bottom-up fabrication of new GO-based tailored materials for electronics, sensors and biological applications.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Graphene oxide (GO) exfoliated sheets were used as two dimensional platforms to covalently tether on their surface thousands of optically active quaterthiophene molecules (T4), using an innovative microwave-assisted silanization reaction. This method allowed to perform GO functionalization in one-step, under mild conditions in a few tens of minutes rather than days. The hybrid GOT4 could be processed in either H2O or apolar organic solvents and deposited as single sheets, microplatelets or macroscopic membranes. Absorption/emission spectroscopy reveals that GOT4 combines limited T4-T4 interactions with strong T4-GO ones. These findings, combined with the `user-friendly' engineering approach presented here, pave the way towards the bottom-up fabrication of new GO-based tailored materials for electronics, sensors and biological applications. |
Orgiu, Emanuele ; Crivillers, Nuria ; Rotzler, Juergen ; Mayor, Marcel ; Samori, Paolo Tuning the charge injection of P3HT-based organic thin-film transistors through electrode functionalization with oligophenylene SAMs Journal Article In: JOURNAL OF MATERIALS CHEMISTRY, 20 (48), pp. 10798–10800, 2010, ISSN: 0959-9428. @article{orgiu_tuning_2010, title = {Tuning the charge injection of P3HT-based organic thin-film transistors through electrode functionalization with oligophenylene SAMs}, author = {Orgiu, Emanuele and Crivillers, Nuria and Rotzler, Juergen and Mayor, Marcel and Samori, Paolo}, doi = {10.1039/c0jm03363d}, issn = {0959-9428}, year = {2010}, date = {2010-01-01}, journal = {JOURNAL OF MATERIALS CHEMISTRY}, volume = {20}, number = {48}, pages = {10798--10800}, abstract = {Field-effect mobility and threshold voltage are modulated by functionalizing gold electrodes with chemisorbed SAMs of aromatic thiols having an increasing number of phenylenes. The contact resistance in poly(3-hexylthiophene)-based TFTs was found to be ruled by the joint effect of the energetic alignment between metal and semiconductor, the interfacial morphology and tunneling resistance of the SAMs.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Field-effect mobility and threshold voltage are modulated by functionalizing gold electrodes with chemisorbed SAMs of aromatic thiols having an increasing number of phenylenes. The contact resistance in poly(3-hexylthiophene)-based TFTs was found to be ruled by the joint effect of the energetic alignment between metal and semiconductor, the interfacial morphology and tunneling resistance of the SAMs. |
Dabirian, R; Feng, X; Ortolani, L; Liscio, A; Morandi, V; Muellen, K; Samori, P; Palermo, V Micron-sized [6,6]-phenyl C61 butyric acid methyl ester crystals grown by dip coating in solvent vapour atmosphere: interfaces for organic photovoltaics Journal Article In: PHYSICAL CHEMISTRY CHEMICAL PHYSICS, 12 (17), pp. 4473–4480, 2010, ISSN: 1463-9076. @article{dabirian_micron-sized_2010, title = {Micron-sized [6,6]-phenyl C61 butyric acid methyl ester crystals grown by dip coating in solvent vapour atmosphere: interfaces for organic photovoltaics}, author = {Dabirian, R. and Feng, X. and Ortolani, L. and Liscio, A. and Morandi, V. and Muellen, K. and Samori, P. and Palermo, V.}, doi = {10.1039/b923496a}, issn = {1463-9076}, year = {2010}, date = {2010-01-01}, journal = {PHYSICAL CHEMISTRY CHEMICAL PHYSICS}, volume = {12}, number = {17}, pages = {4473--4480}, abstract = {We have devised a novel dip coating procedure to form highly crystalline and macroscopic pi-conjugated architectures on solid surfaces. We have employed this approach to a technologically relevant system, i.e. the electron-acceptor [6,6]-phenyl C61 butyric acid methyl ester molecule (PCBM), which is the most commonly used electron-acceptor in organic photovoltaics. Highly ordered, hexagonal shaped crystals of PCBM, ranging between 1 to 80 mm in diameter and from 20 to 500 nm in thickness, have been grown by dip coating the substrates into a solution containing the fullerene derivative. These crystals have been found to possess a monocrystalline character, to exhibit a hexagonal symmetry and to display micron sized molecularly. at terraces. The crystals have been prepared on a wide variety of surfaces such as SiO(x), silanized SiO(x), Au, graphite, amorphous carbon-copper grids and ITO. Their multiscale characterization has been performed by atomic force microscopy (AFM), Kelvin probe force microscopy (KPFM), X-ray diffraction (XRD), optical microscopy, scanning and transmission electron microscopy (SEM, TEM). To test the stability of these electron accepting PCBM crystals, they have been coated with a complementary, electron donor hexa-peri-hexabenzocoronene (HBC) derivative by solution processing from acetone and chloroform-methanol blends. The HBC self assembles in a well-defined network of nanofibers on the PCBM substrate, and the two materials can be clearly resolved by AFM and KPFM. Due to its structural precision on the macroscopic scale, the PCBM crystals appear as ideal interface to perform fundamental photophysical studies in electron-acceptor and-donor blends, as well as workbench for unravelling the architecture vs. function relationship in organic solar cells prototypes.}, keywords = {}, pubstate = {published}, tppubtype = {article} } We have devised a novel dip coating procedure to form highly crystalline and macroscopic pi-conjugated architectures on solid surfaces. We have employed this approach to a technologically relevant system, i.e. the electron-acceptor [6,6]-phenyl C61 butyric acid methyl ester molecule (PCBM), which is the most commonly used electron-acceptor in organic photovoltaics. Highly ordered, hexagonal shaped crystals of PCBM, ranging between 1 to 80 mm in diameter and from 20 to 500 nm in thickness, have been grown by dip coating the substrates into a solution containing the fullerene derivative. These crystals have been found to possess a monocrystalline character, to exhibit a hexagonal symmetry and to display micron sized molecularly. at terraces. The crystals have been prepared on a wide variety of surfaces such as SiO(x), silanized SiO(x), Au, graphite, amorphous carbon-copper grids and ITO. Their multiscale characterization has been performed by atomic force microscopy (AFM), Kelvin probe force microscopy (KPFM), X-ray diffraction (XRD), optical microscopy, scanning and transmission electron microscopy (SEM, TEM). To test the stability of these electron accepting PCBM crystals, they have been coated with a complementary, electron donor hexa-peri-hexabenzocoronene (HBC) derivative by solution processing from acetone and chloroform-methanol blends. The HBC self assembles in a well-defined network of nanofibers on the PCBM substrate, and the two materials can be clearly resolved by AFM and KPFM. Due to its structural precision on the macroscopic scale, the PCBM crystals appear as ideal interface to perform fundamental photophysical studies in electron-acceptor and-donor blends, as well as workbench for unravelling the architecture vs. function relationship in organic solar cells prototypes. |
Osorio, Edgar A; Ruben, Mario ; Seldenthuis, Johannes S; Lehn, Jean-Marie ; van der Zant, Herre S J Conductance Switching and Vibrational Fine Structure of a [2 x 2] Co-4(II) Gridlike Single Molecule Measured in a Three-Terminal Device Journal Article In: SMALL, 6 (2), pp. 174–178, 2010, ISSN: 1613-6810. @article{osorio_conductance_2010, title = {Conductance Switching and Vibrational Fine Structure of a [2 x 2] Co-4(II) Gridlike Single Molecule Measured in a Three-Terminal Device}, author = {Osorio, Edgar A. and Ruben, Mario and Seldenthuis, Johannes S. and Lehn, Jean-Marie and van der Zant, Herre S. J.}, doi = {10.1002/smll.200901559}, issn = {1613-6810}, year = {2010}, date = {2010-01-01}, journal = {SMALL}, volume = {6}, number = {2}, pages = {174--178}, keywords = {}, pubstate = {published}, tppubtype = {article} } |
Lehn, Jean-Marie Dynamers: Dynamic Molecular and Supramolecular Polymers Journal Article In: AUSTRALIAN JOURNAL OF CHEMISTRY, 63 (4), pp. 611–623, 2010, ISSN: 0004-9425. @article{lehn_dynamers:_2010, title = {Dynamers: Dynamic Molecular and Supramolecular Polymers}, author = {Lehn, Jean-Marie}, doi = {10.1071/CH10035}, issn = {0004-9425}, year = {2010}, date = {2010-01-01}, journal = {AUSTRALIAN JOURNAL OF CHEMISTRY}, volume = {63}, number = {4}, pages = {611--623}, abstract = {Dynamers are defined as constitutional dynamic polymers, i.e. polymeric entities whose monomeric components are linked through reversible connections and have therefore the capacity to modify their constitution by exchange and reshuffling of their components. They may be either of supramolecular or molecular nature depending on whether the connections are non-covalent interactions or reversible covalent bonds. They are formed respectively either by polyassociation with interactional recognition or by polycondensation with functional recognition between the connecting subunits. Both types are illustrated by specific examples implementing hydrogen bonding on one hand and formation of imine-type bonds on the other. The dynamic properties confer to dynamers the ability to undergo adaptation and driven evolution under the effect of external chemical or physical triggers. Dynamers thus are constitutional dynamic materials resulting from the application of the principles of constitutional dynamic chemistry to polymer science.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Dynamers are defined as constitutional dynamic polymers, i.e. polymeric entities whose monomeric components are linked through reversible connections and have therefore the capacity to modify their constitution by exchange and reshuffling of their components. They may be either of supramolecular or molecular nature depending on whether the connections are non-covalent interactions or reversible covalent bonds. They are formed respectively either by polyassociation with interactional recognition or by polycondensation with functional recognition between the connecting subunits. Both types are illustrated by specific examples implementing hydrogen bonding on one hand and formation of imine-type bonds on the other. The dynamic properties confer to dynamers the ability to undergo adaptation and driven evolution under the effect of external chemical or physical triggers. Dynamers thus are constitutional dynamic materials resulting from the application of the principles of constitutional dynamic chemistry to polymer science. |
Godin, Guillaume ; Levrand, Barbara ; Trachsel, Alain ; Lehn, Jean-Marie ; Herrmann, Andreas Reversible formation of aminals: a new strategy to control the release of bioactive volatiles from dynamic mixtures Journal Article In: CHEMICAL COMMUNICATIONS, 46 (18), pp. 3125–3127, 2010, ISSN: 1359-7345. @article{godin_reversible_2010, title = {Reversible formation of aminals: a new strategy to control the release of bioactive volatiles from dynamic mixtures}, author = {Godin, Guillaume and Levrand, Barbara and Trachsel, Alain and Lehn, Jean-Marie and Herrmann, Andreas}, doi = {10.1039/c002302g}, issn = {1359-7345}, year = {2010}, date = {2010-01-01}, journal = {CHEMICAL COMMUNICATIONS}, volume = {46}, number = {18}, pages = {3125--3127}, abstract = {Dynamic mixtures generated by reversible aminal formation of fragrance aldehydes with N,N'-dibenzyl alkyldiamines in aqueous systems were found to be suitable delivery systems for the controlled release of bioactive volatiles.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Dynamic mixtures generated by reversible aminal formation of fragrance aldehydes with N,N'-dibenzyl alkyldiamines in aqueous systems were found to be suitable delivery systems for the controlled release of bioactive volatiles. |
Lao, Luciana Lisa ; Schmitt, Jean-Louis ; Lehn, Jean-Marie Evolution of a Constitutional Dynamic Library Driven by Self-Organisation of a Helically Folded Molecular Strand Journal Article In: CHEMISTRY-A EUROPEAN JOURNAL, 16 (16), pp. 4903–4910, 2010, ISSN: 0947-6539. @article{lao_evolution_2010, title = {Evolution of a Constitutional Dynamic Library Driven by Self-Organisation of a Helically Folded Molecular Strand}, author = {Lao, Luciana Lisa and Schmitt, Jean-Louis and Lehn, Jean-Marie}, doi = {10.1002/chem.200903437}, issn = {0947-6539}, year = {2010}, date = {2010-01-01}, journal = {CHEMISTRY-A EUROPEAN JOURNAL}, volume = {16}, number = {16}, pages = {4903--4910}, abstract = {Conversion of macrocyclic imine entities into helical strands was achieved through three- and four-component exchange reactions within constitutionally dynamic libraries. The generation of sequences of the intrinsic helicity codon, based on the hydrazone pyrimidine fragment obtained by condensation of pyrimidine dialdehyde A with pyrimidine bis-hydrazine B, shifted the equilibrium between all the possible macrocycles and strands towards the full expression (textbackslashtextbackslashtextgreater98%) of helical product [A/B]. Furthermore, it was shown that chain folding accelerated the dynamic exchange reactions among the library members. Lastly, in four-component experiments (involving A. B. E and either C or D), even though the macrocyclic entities ([A/C], [B/E]: [A/D], [B/E]) were the kinetically preferred products, over time dialdehyde A relinquished its initial diamine partners C or I) to opt for bis-hydrazine B, which allowed the preferential formation of the helically folded strand. The present results indicate that self-organisation pressure was able to drive the dynamic system towards the selective generation of the strand undergoing helical folding.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Conversion of macrocyclic imine entities into helical strands was achieved through three- and four-component exchange reactions within constitutionally dynamic libraries. The generation of sequences of the intrinsic helicity codon, based on the hydrazone pyrimidine fragment obtained by condensation of pyrimidine dialdehyde A with pyrimidine bis-hydrazine B, shifted the equilibrium between all the possible macrocycles and strands towards the full expression (textbackslashtextbackslashtextgreater98%) of helical product [A/B]. Furthermore, it was shown that chain folding accelerated the dynamic exchange reactions among the library members. Lastly, in four-component experiments (involving A. B. E and either C or D), even though the macrocyclic entities ([A/C], [B/E]: [A/D], [B/E]) were the kinetically preferred products, over time dialdehyde A relinquished its initial diamine partners C or I) to opt for bis-hydrazine B, which allowed the preferential formation of the helically folded strand. The present results indicate that self-organisation pressure was able to drive the dynamic system towards the selective generation of the strand undergoing helical folding. |
Publications
2010 |
From filamentary clouds to prestellar cores to the stellar IMF: Initial highlights from the Herschel Gould Belt Survey Journal Article In: ASTRONOMY & ASTROPHYSICS, 518 , 2010, ISSN: 0004-6361. |
The Herschel Space Observatory view of dust in M81 Journal Article In: ASTRONOMY & ASTROPHYSICS, 518 , 2010, ISSN: 1432-0746. |
Mapping the interstellar medium in galaxies with Herschel Journal Article In: ASTRONOMY & ASTROPHYSICS, 518 , 2010, ISSN: 0004-6361. |
The dust morphology of the elliptical Galaxy M 86 with SPIRE Journal Article In: ASTRONOMY & ASTROPHYSICS, 518 , 2010, ISSN: 0004-6361. |
Determining dust temperatures and masses in the Herschel era: The importance of observations longward of 200 micron Journal Article In: ASTRONOMY & ASTROPHYSICS, 518 , 2010, ISSN: 1432-0746. |
In Vivo Efficacy of Natural Product-Inspired Irreversible Kinase Inhibitors Journal Article In: CHEMBIOCHEM, 11 (12), pp. 1692–1699, 2010, ISSN: 1439-4227. |
The central region of spiral galaxies as seen by Herschel Journal Article In: ASTRONOMY & ASTROPHYSICS, 518 , 2010, ISSN: 0004-6361. |
Autoactivation of Transforming Growth Factor beta-activated Kinase 1 Is a Sequential Bimolecular Process Journal Article In: JOURNAL OF BIOLOGICAL CHEMISTRY, 285 (33), pp. 25753–25766, 2010, ISSN: 0021-9258. |
1,2-Dicyano-4,5-bis[2 `-(2 `'-benzyloxyethoxy)ethoxy]benzene - precursor towards new functionalized phthalocyanines Journal Article In: MENDELEEV COMMUNICATIONS, 20 (4), pp. 237–238, 2010, ISSN: 0959-9436. |
Colloidal Quantum Dots as Probes of Excitation Field Enhancement in Photonic Antennas Journal Article In: ACS NANO, 4 (8), pp. 4571–4578, 2010, ISSN: 1936-0851. |
Extraordinary Optical Transmission Enhanced by Nanofocusing Journal Article In: NANO LETTERS, 10 (8), pp. 3123–3128, 2010, ISSN: 1530-6984. |
Conformational Free-Energy Difference of a Miniprotein from Nonequilibrium Simulations Journal Article In: JOURNAL OF PHYSICAL CHEMISTRY LETTERS, 1 (13), pp. 1922–1926, 2010, ISSN: 1948-7185. |
XPS investigation of surface changes during thermal aging of Natural Gas Vehicle catalysts: Influence of Rh addition to Pd Journal Article In: SURFACE AND INTERFACE ANALYSIS, 42 (6-7, SI), pp. 530–535, 2010, ISSN: 0142-2421. |
Enhanced luminescence properties of highly threaded conjugated polyelectrolytes with potassium counter-ions upon blending with poly(ethylene oxide) Journal Article In: JOURNAL OF APPLIED PHYSICS, 107 (12), 2010, ISSN: 0021-8979. |
Protein dynamics investigated by inherent structure analysis Journal Article In: PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA, 107 (20), pp. 9152–9157, 2010, ISSN: 0027-8424. |
Metallo-Controlled Dynamic Molecular Tweezers: Design, Synthesis, and Self-Assembly by Metal-Ion Coordination Journal Article In: EUROPEAN JOURNAL OF INORGANIC CHEMISTRY, (13), pp. 1913–1928, 2010, ISSN: 1434-1948. |
Molecular Editing of Kinase-Targeting Resorcylic Acid Lactones (RAL): Fluoroenone RAL Journal Article In: CHEMMEDCHEM, 5 (5), pp. 670–673, 2010, ISSN: 1860-7179. |
Templated Synthesis of Cyclic [4]Rotaxanes Consisting of Two Stiff Rods Threaded through Two Bis-macrocycles with a Large and Rigid Central Plate as Spacer Journal Article In: JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, 132 (19), pp. 6840–6850, 2010, ISSN: 0002-7863. |
Optimization of bull's eye structures for transmission enhancement Journal Article In: OPTICS EXPRESS, 18 (11), pp. 11292–11299, 2010, ISSN: 1094-4087. |
Role of conformation transitions in adenylate kinase Journal Article In: PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA, 107 (17), pp. E71, 2010, ISSN: 0027-8424. |
Pi Release from Myosin: A Simulation Analysis of Possible Pathways Journal Article In: STRUCTURE, 18 (4), pp. 458–470, 2010, ISSN: 0969-2126. |
Dynamical aspects of molecular recognition Introduction Journal Article In: JOURNAL OF MOLECULAR RECOGNITION, 23 (2, SI), pp. 102–104, 2010, ISSN: 0952-3499. |
Synthesis, Characterization, and Surface Initiated Polymerization of Carbazole Functionalized Isocyanides Journal Article In: CHEMISTRY OF MATERIALS, 22 (8), pp. 2597–2607, 2010, ISSN: 0897-4756. |
Nanoscale Quantitative Measurement of the Potential of Charged Nanostructures by Electrostatic and Kelvin Probe Force Microscopy: Unraveling Electronic Processes in Complex Materials Journal Article In: ACCOUNTS OF CHEMICAL RESEARCH, 43 (4), pp. 541–550, 2010, ISSN: 0001-4842. |
Glycodynamers: Dynamic Polymers Bearing Oligosaccharides Residues - Generation, Structure, Physicochemical, Component Exchange, and Lectin Binding Properties Journal Article In: JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, 132 (8), pp. 2573–2584, 2010, ISSN: 0002-7863. |
Coordination Chemistry-Assembled Porphyrinic Catenanes Journal Article In: JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, 132 (12), pp. 4409–4417, 2010, ISSN: 0002-7863. |
From chemical topology to molecular machines Journal Article In: COMPTES RENDUS CHIMIE, 13 (3, SI), pp. 315–328, 2010, ISSN: 1631-0748. |
Light passing through subwavelength apertures Journal Article In: REVIEWS OF MODERN PHYSICS, 82 (1), pp. 729–787, 2010, ISSN: 0034-6861. |
PR65, the HEAT-repeat scaffold of phosphatase PP2A, is an elastic connector that links force and catalysis Journal Article In: PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA, 107 (6), pp. 2467–2472, 2010, ISSN: 0027-8424. |
Macromolecular Scaffolding: The Relationship Between Nanoscale Architecture and Function in Multichromophoric Arrays for Organic Electronics Journal Article In: ADVANCED MATERIALS, 22 (8), pp. E81+, 2010, ISSN: 0935-9648. |
Polarization control of non-diffractive helical optical beams through subwavelength metallic apertures Journal Article In: NEW JOURNAL OF PHYSICS, 12 , 2010, ISSN: 1367-2630. |
Mechanical Coupling in Myosin V: A Simulation Study Journal Article In: JOURNAL OF MOLECULAR BIOLOGY, 395 (4), pp. 815–833, 2010, ISSN: 0022-2836. |
The Mechanism of the Translocation Step in DNA Replication by DNA Polymerase I: A Computer Simulation Analysis Journal Article In: STRUCTURE, 18 (1), pp. 83–93, 2010, ISSN: 0969-2126. |
Entrapment and Structure of an Extrahelical Guanine Attempting to Enter the Active Site of a Bacterial DNA Glycosylase, MutM Journal Article In: JOURNAL OF BIOLOGICAL CHEMISTRY, 285 (2), pp. 1468–1478, 2010, ISSN: 0021-9258. |
Dynamers at the Solid-Liquid Interface: Controlling the Reversible Assembly/Reassembly Process between Two Highly Ordered Supramolecular Guanine Motifs Journal Article In: ANGEWANDTE CHEMIE-INTERNATIONAL EDITION, 49 (11), pp. 1963–1966, 2010, ISSN: 1433-7851. |
Light-responsive reversible solvation and precipitation of gold nanoparticles Journal Article In: CHEMICAL COMMUNICATIONS, 46 (7), pp. 1147–1149, 2010, ISSN: 1359-7345. |
Enhanced anticancer activity of multi-walled carbon nanotube-methotrexate conjugates using cleavable linkers Journal Article In: CHEMICAL COMMUNICATIONS, 46 (9), pp. 1494–1496, 2010, ISSN: 1359-7345. |
Nanopatterning the surface with ordered supramolecular architectures of N-9-alkylated guanines: STM reveals Journal Article In: CHEMICAL COMMUNICATIONS, 46 (25), pp. 4493–4495, 2010, ISSN: 1359-7345. |
A Conjugated Thiophene-Based Rotaxane: Synthesis, Spectroscopy, and Modeling Journal Article In: CHEMISTRY-A EUROPEAN JOURNAL, 16 (13), pp. 3933–3941, 2010, ISSN: 0947-6539. |
Photoswitching Vertically Oriented Azobenzene Self-Assembled Mono layers at the Solid-Liquid Interface Journal Article In: CHEMISTRY-A EUROPEAN JOURNAL, 16 (48), pp. 14256–14260, 2010, ISSN: 0947-6539. |
Phase separation and affinity between a fluorinated perylene diimide dye and an alkyl-substituted hexa-peri-hexabenzocoronene Journal Article In: JOURNAL OF MATERIALS CHEMISTRY, 20 (1), pp. 71–82, 2010, ISSN: 0959-9428. |
Solvent vapour annealing of organic thin films: controlling the self-assembly of functional systems across multiple length scales Journal Article In: JOURNAL OF MATERIALS CHEMISTRY, 20 (13), pp. 2493–2498, 2010, ISSN: 0959-9428. |
Solid-solid transfer of organic semiconductors for field-effect transistor fabrication Journal Article In: JOURNAL OF MATERIALS CHEMISTRY, 20 (41), pp. 9018–9021, 2010, ISSN: 0959-9428. |
Facile covalent functionalization of graphene oxide using microwaves: bottom-up development of functional graphitic materials Journal Article In: JOURNAL OF MATERIALS CHEMISTRY, 20 (41), pp. 9052–9060, 2010, ISSN: 0959-9428. |
Tuning the charge injection of P3HT-based organic thin-film transistors through electrode functionalization with oligophenylene SAMs Journal Article In: JOURNAL OF MATERIALS CHEMISTRY, 20 (48), pp. 10798–10800, 2010, ISSN: 0959-9428. |
Micron-sized [6,6]-phenyl C61 butyric acid methyl ester crystals grown by dip coating in solvent vapour atmosphere: interfaces for organic photovoltaics Journal Article In: PHYSICAL CHEMISTRY CHEMICAL PHYSICS, 12 (17), pp. 4473–4480, 2010, ISSN: 1463-9076. |
Conductance Switching and Vibrational Fine Structure of a [2 x 2] Co-4(II) Gridlike Single Molecule Measured in a Three-Terminal Device Journal Article In: SMALL, 6 (2), pp. 174–178, 2010, ISSN: 1613-6810. |
Dynamers: Dynamic Molecular and Supramolecular Polymers Journal Article In: AUSTRALIAN JOURNAL OF CHEMISTRY, 63 (4), pp. 611–623, 2010, ISSN: 0004-9425. |
Reversible formation of aminals: a new strategy to control the release of bioactive volatiles from dynamic mixtures Journal Article In: CHEMICAL COMMUNICATIONS, 46 (18), pp. 3125–3127, 2010, ISSN: 1359-7345. |
Evolution of a Constitutional Dynamic Library Driven by Self-Organisation of a Helically Folded Molecular Strand Journal Article In: CHEMISTRY-A EUROPEAN JOURNAL, 16 (16), pp. 4903–4910, 2010, ISSN: 0947-6539. |