@article {2022|2156, title = {Building Biological Relevance Into Integrative Modelling of Macromolecular Assemblies}, journal = {Frontiers in Molecular Biosciences}, volume = {9}, year = {2022}, pages = {826136}, abstract = {

Recent advances in structural biophysics and integrative modelling methods now allow us to decipher the structures of large macromolecular assemblies. Understanding the dynamics and mechanisms involved in their biological function requires rigorous integration of all available data. We have developed a complete modelling pipeline that includes analyses to extract biologically significant information by consistently combining automated and interactive human-guided steps. We illustrate this idea with two examples. First, we describe the ryanodine receptor, an ion channel that controls ion flux across the cell membrane through transitions between open and closed states. The conformational changes associated with the transitions are small compared to the considerable system size of the receptor; it is challenging to consistently track these states with the available cryo-EM structures. The second example involves homologous recombination, in which long filaments of a recombinase protein and DNA catalyse the exchange of homologous DNA strands to reliably repair DNA double-strand breaks. The nucleoprotein filament reaction intermediates in this process are short-lived and heterogeneous, making their structures particularly elusive. The pipeline we describe, which incorporates experimental and theoretical knowledge combined with state-of-the-art interactive and immersive modelling tools, can help overcome these challenges. In both examples, we point to new insights into biological processes that arise from such interdisciplinary approaches.

}, issn = {2296-889X}, doi = {10.3389/fmolb.2022.826136}, url = {https://www.frontiersin.org/article/10.3389/fmolb.2022.826136}, author = {Molza, Anne-Elisabeth and Westermaier, Yvonne and Moutte, Magali and Ducrot, Pierre and Danilowicz, Claudia and Godoy-Carter, Veronica and Prentiss, Mara and Robert, Charles H. and Marc Baaden and Pr{\'e}vost, Chantal} } @article {2022|2160, title = {Open-channel structure of a pentameric ligand-gated ion channel reveals a mechanism of leaflet-specific phospholipid modulation}, journal = {Nature Communications}, volume = {13}, year = {2022}, doi = {10.1038/s41467-022-34813-5}, url = {https://doi.org/10.1038/s41467-022-34813-5}, author = {John T. Petroff and Noah M. Dietzen and Ezry Santiago-McRae and Brett Deng and Maya S. Washington and Lawrence J. Chen and K. Trent Moreland and Zengqin Deng and Michael Rau and James A. J. Fitzpatrick and Peng Yuan and Thomas T. Joseph and J{\'e}r{\^o}me H{\'e}nin and Grace Brannigan and Wayland W. L. Cheng} } @article {2022|2158, title = {Tripeptide loop closure: A detailed study of reconstructions based on Ramachandran distributions}, journal = {Proteins: Structure, Function, and Bioinformatics}, volume = {90}, year = {2022}, pages = {858-868}, abstract = {

Abstract Tripeptide loop closure (TLC) is a standard procedure to reconstruct protein backbone conformations, by solving a zero-dimensional polynomial system yielding up to 16 solutions. In this work, we first show that multiprecision is required in a TLC solver to guarantee the existence and the accuracy of solutions. We then compare solutions yielded by the TLC solver against tripeptides from the Protein Data Bank. We show that these solutions are geometrically diverse (up to Root mean square deviation with respect to the data) and sound in terms of potential energy. Finally, we compare Ramachandran distributions of data and reconstructions for the three amino acids. The distribution of reconstructions in the second angular space stands out, with a rather uniform distribution leaving a central void. We anticipate that these insights, coupled to our robust implementation in the Structural Bioinformatics Library ( https://sbl.inria.fr/doc/Tripeptide_loop_closure-user-manual.html), will help understanding the properties of TLC reconstructions, with potential applications to the generation of conformations of flexible loops in particular.

}, keywords = {protein loop conformations, Ramachandran diagrams, robust numerics, tripeptide loop closure, tripeptides}, doi = {https://doi.org/10.1002/prot.26281}, url = {https://onlinelibrary.wiley.com/doi/abs/10.1002/prot.26281}, author = {O{\textquoteright}Donnell, Timoth{\'e}e and Robert, Charles H. and Cazals, Fr{\'e}d{\'e}ric} } @article {2021|2155, title = {Modeling Perturbations in Protein Filaments at the Micro and Meso Scale Using NAMD and PTools/Heligeom}, journal = {Bio-protocol}, volume = {11}, year = {2021}, pages = {e4097}, abstract = {

Protein filaments are dynamic entities that respond to external stimuli by slightly or substantially modifying the internal binding geometries between successive protomers. This results in overall changes in the filament architecture, which are difficult to model due to the helical character of the system. Here, we describe how distortions in RecA nucleofilaments and their consequences on the filament-DNA and bound DNA-DNA interactions at different stages of the homologous recombination process can be modeled using the PTools/Heligeom software and subsequent molecular dynamics simulation with NAMD. Modeling methods dealing with helical macromolecular objects typically rely on symmetric assemblies and take advantage of known symmetry descriptors. Other methods dealing with single objects, such as MMTK or VMD, do not integrate the specificities of regular assemblies. By basing the model building on binding geometries at the protomer-protomer level, PTools/Heligeom frees the building process from a priori knowledge of the system topology and enables irregular architectures and symmetry disruption to be accounted for. doi: 10.21769/BioProtoc.4097

}, doi = {10.21769/BioProtoc.4097}, url = {www.bioprotocol.org/e4097}, author = {Boyer, B. and Laurent, B. and Robert, C. H. and Prevost, C.} } @article {2020|2142, title = {Scalable molecular dynamics on CPU and GPU architectures with NAMD}, journal = {The Journal of Chemical Physics}, volume = {153}, year = {2020}, chapter = {044130}, abstract = {

NAMD is a molecular dynamics program designed for high-performance simulations of very large biological objects on CPU- and GPU-based architectures. NAMD offers scalable performance on petascale parallel supercomputers consisting of hundreds of thousands of cores, as well as on inexpensive commodity clusters commonly found in academic environments. It is written in C++ and leans on Charm++ parallel objects for optimal performance on low-latency architectures. NAMD is a versatile, multipurpose code that gathers state-of-the-art algorithms to carry out simulations in apt thermodynamic ensembles, using the widely popular CHARMM, AMBER, OPLS, and GROMOS biomolecular force fields. Here, we review the main features of NAMD that allow both equilibrium and enhanced-sampling molecular dynamics simulations with numerical efficiency. We describe the underlying concepts utilized by NAMD and their implementation, most notably for handling long-range electrostatics; controlling the temperature, pressure, and pH; applying external potentials on tailored grids; leveraging massively parallel resources in multiple-copy simulations; and hybrid quantum-mechanical/molecular-mechanical descriptions. We detail the variety of options offered by NAMD for enhanced-sampling simulations aimed at determining free-energy differences of either alchemical or geometrical transformations and outline their applicability to specific problems. Last, we discuss the roadmap for the development of NAMD and our current efforts toward achieving optimal performance on GPU-based architectures, for pushing back the limitations that have prevented biologically realistic billion-atom objects to be fruitfully simulated, and for making large-scale simulations less expensive and easier to set up, run, and analyze. NAMD is distributed free of charge with its source code at www.ks.uiuc.edu.

}, keywords = {NAMD}, doi = {10.1063/5.0014475}, url = {https://aip.scitation.org/doi/10.1063/5.0014475}, author = {James Phillips and David Hardy and Julio Maia and John Stone and Joao Ribeiro and Rafael Bernardi and Ronak Buch and Giacomo Fiorin and J{\'e}r{\^o}me H{\'e}nin and Wei Jiang and Ryan McGreevy and Melo, Marcelo Cardoso dos Reis and Brian Radak and Robert Skeel and Abhishek Singharoy and Yi Wang and Benoit Roux and Aleksei Aksimentiev and Zan Luthey-Schulten and Laxmikant Kale and Klaus Schulten and Christophe Chipot and Emad Tajkhorshid} } @article {2020|2140, title = {Structural transitions in the RNA 7SK 5{\textquoteright} hairpin and their effect on HEXIM binding}, journal = {Nucleic Acids Res}, volume = {48}, year = {2020}, month = {01}, pages = {373-389}, abstract = {

7SK RNA, as part of the 7SK ribonucleoprotein complex, is crucial to the regulation of transcription by RNA-polymerase II, via its interaction with the positive transcription elongation factor P-TEFb. The interaction is induced by binding of the protein HEXIM to the 5\&$\#$39; hairpin (HP1) of 7SK RNA. Four distinct structural models have been obtained experimentally for HP1. Here, we employ computational methods to investigate the relative stability of these structures, transitions between them, and the effects of mutations on the observed structural ensembles. We further analyse the results with respect to mutational binding assays, and hypothesize a mechanism for HEXIM binding. Our results indicate that the dominant structure in the wild type exhibits a triplet involving the unpaired nucleotide U40 and the base pair A43-U66 in the GAUC/GAUC repeat. This conformation leads to an open major groove with enough potential binding sites for peptide recognition. Sequence mutations of the RNA change the relative stability of the different structural ensembles. Binding affinity is consequently lost if these changes alter the dominant structure.

}, doi = {10.1093/nar/gkz1071}, author = {R{\"o}der, Konstantin and Guillaume Stirnemann and Dock-Bregeon, Anne-Catherine and Wales, David J and Pasquali, Samuela} } @article {2020|2077, title = {Visualizing biomolecular electrostatics in virtual reality with UnityMol-APBS.}, journal = {Protein Sci}, volume = {29}, year = {2020}, month = {2020 Jan}, pages = {237-246}, abstract = {

Virtual reality is a powerful tool with the ability to immerse a user within a completely external environment. This immersion is particularly useful when visualizing and analyzing interactions between small organic molecules, molecular inorganic complexes, and biomolecular systems such as redox proteins and enzymes. A common tool used in the biomedical community to analyze such interactions is the Adaptive Poisson-Boltzmann Solver (APBS) software, which was developed to solve the equations of continuum electrostatics for large biomolecular assemblages. Numerous applications exist for using APBS in the biomedical community including analysis of protein ligand interactions and APBS has enjoyed widespread adoption throughout the biomedical community. Currently, typical use of the full APBS toolset is completed via the command line followed by visualization using a variety of two-dimensional external molecular visualization software. This process has inherent limitations: visualization of three-dimensional objects using a two-dimensional interface masks important information within the depth component. Herein, we have developed a single application, UnityMol-APBS, that provides a dual experience where users can utilize the full range of the APBS toolset, without the use of a command line interface, by use of a simple graphical user interface (GUI) for either a standard desktop or immersive virtual reality experience.

}, issn = {1469-896X}, doi = {10.1002/pro.3773}, author = {Laureanti, Joseph and Brandi, Juan and Offor, Elvis and Engel, David and Rallo, Robert and Ginovska, Bojana and Martinez, Xavier and Marc Baaden and Baker, Nathan A} } @article {2019|2070, title = {Design games and game design: Relations between design, codesign and serious games in adult education}, journal = {From UXD to LivXD: Living eXperience Design}, year = {2019}, pages = {229{\textendash}253}, author = {Alvarez, Julian and Irrmann, Olivier and Djaouti, Damien and Antoine Taly and Rampnoux, Olivier and Sauv{\'e}, Louise} } @article {2019|2079, title = {Molecular Graphics: Bridging Structural Biologists and Computer Scientists.}, journal = {Structure}, volume = {27}, year = {2019}, month = {2019 11 05}, pages = {1617-1623}, abstract = {

Visualization of molecular structures is one of the most common tasks carried out by structural biologists, typically using software, such as Chimera, COOT, PyMOL, or VMD. In this Perspective article, we outline how past developments in computer graphics and data visualization have expanded the understanding of biomolecular function, and we summarize recent advances that promise to further transform structural biology. We also highlight how progress in molecular graphics has been impeded by communication barriers between two communities: the computer scientists driving these advances, and the structural and computational biologists who stand to benefit. By pointing to canonical papers and explaining technical progress underlying new graphical developments in simple terms, we aim to improve communication between these communities; this, in turn, would help shape future developments in molecular graphics.

}, issn = {1878-4186}, doi = {10.1016/j.str.2019.09.001}, author = {Martinez, Xavier and Krone, Michael and Alharbi, Naif and Rose, Alexander S and Laramee, Robert S and O{\textquoteright}Donoghue, Sean and Marc Baaden and Chavent, Matthieu} } @article {2018|2134, title = {DNA Binding Induces a Nanomechanical Switch in the RRM1 Domain of TDP-43}, journal = {J Phys Chem Lett}, volume = {9}, year = {2018}, month = {Jul}, pages = {3800-3807}, abstract = {

Understanding the molecular mechanisms governing protein-nucleic acid interactions is fundamental to many nuclear processes. However, how nucleic acid binding affects the conformation and dynamics of the substrate protein remains poorly understood. Here we use a combination of single molecule force spectroscopy AFM and biochemical assays to show that the binding of TG-rich ssDNA triggers a mechanical switch in the RRM1 domain of TDP-43, toggling between an entropic spring devoid of mechanical stability and a shock absorber bound-form that resists unfolding forces of \∼40 pN. The fraction of mechanically resistant proteins correlates with an increasing length of the TG n oligonucleotide, demonstrating that protein mechanical stability is a direct reporter of nucleic acid binding. Steered molecular dynamics simulations on related RNA oligonucleotides reveal that the increased mechanical stability fingerprinting the holo-form is likely to stem from a unique scenario whereby the nucleic acid acts as a \"mechanical staple\" that protects RRM1 from mechanical unfolding. Our approach highlights nucleic acid binding as an effective strategy to control protein nanomechanics.

}, doi = {10.1021/acs.jpclett.8b01494}, author = {Wang, Yong Jian and Rico-Lastres, Palma and Lezamiz, Ainhoa and Mora, Marc and Solsona, Carles and Guillaume Stirnemann and Garcia-Manyes, Sergi} } @article {2018|2093, title = {Dystrophin{\textquoteright}s central domain forms a complex filament that becomes disorganized by in-frame deletions.}, journal = {J Biol Chem}, volume = {293}, year = {2018}, month = {2018 05 04}, pages = {6637-6646}, abstract = {

Dystrophin, encoded by the gene, is critical for maintaining plasma membrane integrity during muscle contraction events. Mutations in the gene disrupting the reading frame prevent dystrophin production and result in severe Duchenne muscular dystrophy (DMD); in-frame internal deletions allow production of partly functional internally deleted dystrophin and result in less severe Becker muscular dystrophy (BMD). Many known BMD deletions occur in dystrophin\&$\#$39;s central domain, generally considered to be a monotonous rod-shaped domain based on the knowledge of spectrin family proteins. However, the effects caused by these deletions, ranging from asymptomatic to severe BMD, argue against the central domain serving only as a featureless scaffold. We undertook structural studies combining small-angle X-ray scattering and molecular modeling in an effort to uncover the structure of the central domain, as dystrophin has been refractory to characterization. We show that this domain appears to be a tortuous and complex filament that is profoundly disorganized by the most severe BMD deletion (loss of exons 45-47). Despite the preservation of large parts of the binding site for neuronal nitric oxide synthase (nNOS) in this deletion, computational approaches failed to recreate the association of dystrophin with nNOS. This observation is in agreement with a strong decrease of nNOS immunolocalization in muscle biopsies, a parameter related to the severity of BMD phenotypes. The structural description of the whole dystrophin central domain we present here is a first necessary step to improve the design of microdystrophin constructs toward the goal of a successful gene therapy for DMD.

}, keywords = {Binding Sites, Dystrophin, Exons, Gene Deletion, Humans, Molecular Docking Simulation, Muscular Dystrophy, Duchenne, Nitric Oxide Synthase Type I, Protein Domains, Reading Frames, Scattering, Small Angle, Solutions, X-Ray Diffraction}, issn = {1083-351X}, doi = {10.1074/jbc.M117.809798}, author = {Delalande, Olivier and Molza, Anne-Elisabeth and Dos Santos Morais, Raphael and Ch{\'e}ron, Ang{\'e}lique and Pollet, {\'E}meline and Raguenes-Nicol, C{\'e}line and Tascon, Christophe and Giudice, Emmanuel and Guilbaud, Marine and Nicolas, Aur{\'e}lie and Bondon, Arnaud and Leturcq, France and Nicolas F{\'e}rey and Marc Baaden and Perez, Javier and Roblin, Pierre and Pi{\'e}tri-Rouxel, France and Hubert, Jean-Fran{\c c}ois and Czjzek, Mirjam and Le Rumeur, Elisabeth} } @article {2018|2094, title = {Holding the Nucleosome Together: A Quantitative Description of the DNA-Histone Interface in Solution.}, journal = {J Chem Theory Comput}, volume = {14}, year = {2018}, month = {2018 Feb 13}, pages = {1045-1058}, abstract = {

The nucleosome is the fundamental unit of eukaryotic genome packaging in the chromatin. In this complex, the DNA wraps around eight histone proteins to form a superhelical double helix. The resulting bending, stronger than anything observed in free DNA, raises the question of how such a distortion is stabilized by the proteic and solvent environments. In this work, the DNA-histone interface in solution was exhaustively analyzed from nucleosome structures generated by molecular dynamics. An original Voronoi tessellation technique, measuring the topology of interacting elements without any empirical or subjective adjustment, was used to characterize the interface in terms of contact area and occurrence. Our results revealed an interface more robust than previously known, combining extensive, long-lived nonelectrostatic and electrostatic interactions between DNA and both structured and unstructured histone regions. Cation accumulation makes the proximity of juxtaposed DNA gyres in the superhelix possible by shielding the strong electrostatic repulsion of the charged phosphate groups. Overall, this study provides new insights on the nucleosome cohesion, explaining how DNA distortions can be maintained in a nucleoprotein complex.

}, keywords = {DNA, Histones, Molecular Dynamics Simulation, Nucleosomes, Solutions, Static Electricity}, issn = {1549-9626}, doi = {10.1021/acs.jctc.7b00936}, author = {Elbahnsi, Ahmad and Retureau, Romain and Marc Baaden and Hartmann, Brigitte and Oguey, Christophe} } @article {2018|2087, title = {The major β-catenin/E-cadherin junctional binding site is a primary molecular mechano-transductor of differentiation .}, journal = {Elife}, volume = {7}, year = {2018}, month = {2018 07 19}, abstract = {

, the primary molecular mechanotransductive events mechanically initiating cell differentiation remain unknown. Here we find the molecular stretching of the highly conserved Y654-β-catenin-D665-E-cadherin binding site as mechanically induced by tissue strain. It triggers the increase of accessibility of the Y654 site, target of the Src42A kinase phosphorylation leading to irreversible unbinding. Molecular dynamics simulations of the β-catenin/E-cadherin complex under a force mimicking a 6 pN physiological mechanical strain predict a local 45\% stretching between the two α-helices linked by the site and a 15\% increase in accessibility of the phosphorylation site. Both are quantitatively observed using FRET lifetime imaging and non-phospho Y654 specific antibody labelling, in response to the mechanical strains developed by endogenous and magnetically mimicked early mesoderm invagination of gastrulating embryos. This is followed by the predicted release of 16\% of β-catenin from junctions, observed in FRAP, which initiates the mechanical activation of the β-catenin pathway process.

}, keywords = {Amino Acid Sequence, Animals, Armadillo Domain Proteins, Binding Sites, Cadherins, Cell Differentiation, Drosophila melanogaster, Drosophila Proteins, Fluorescence Resonance Energy Transfer, Mechanotransduction, Cellular, Molecular Dynamics Simulation, Phosphorylation, Protein Binding, Protein Conformation, Proto-Oncogene Proteins pp60(c-src), Sequence Homology, Transcription Factors}, issn = {2050-084X}, doi = {10.7554/eLife.33381}, author = {R{\"o}per, Jens-Christian and Mitrossilis, D{\'e}mosth{\`e}ne and Guillaume Stirnemann and Waharte, Fran{\c c}ois and Brito, Isabel and Fernandez-Sanchez, Maria-Elena and Marc Baaden and Salamero, Jean and Farge, Emmanuel} } @article {2018|2044, title = {Meet-U: Educating through research immersion}, journal = {PLOS Computational Biology}, volume = {14}, year = {2018}, month = {03}, pages = {1-10}, abstract = {

We present a new educational initiative called Meet-U that aims to train students for collaborative work in computational biology and to bridge the gap between education and research. Meet-U mimics the setup of collaborative research projects and takes advantage of the most popular tools for collaborative work and of cloud computing. Students are grouped in teams of 4\–5 people and have to realize a project from A to Z that answers a challenging question in biology. Meet-U promotes \"coopetition,\" as the students collaborate within and across the teams and are also in competition with each other to develop the best final product. Meet-U fosters interactions between different actors of education and research through the organization of a meeting day, open to everyone, where the students present their work to a jury of researchers and jury members give research seminars. This very unique combination of education and research is strongly motivating for the students and provides a formidable opportunity for a scientific community to unite and increase its visibility. We report on our experience with Meet-U in two French universities with master\’s students in bioinformatics and modeling, with protein\–protein docking as the subject of the course. Meet-U is easy to implement and can be straightforwardly transferred to other fields and/or universities. All the information and data are available at www.meet-u.org.

}, doi = {10.1371/journal.pcbi.1005992}, url = {https://doi.org/10.1371/journal.pcbi.1005992}, author = {Abdollahi, Nika and Albani, Alexandre and Anthony, Eric and Baud, Agnes and Cardon, M{\'e}lissa and Clerc, Robert and Czernecki, Dariusz and Conte, Romain and David, Laurent and Delaune, Agathe and Djerroud, Samia and Fourgoux, Pauline and Guiglielmoni, Nad{\`e}ge and Laurentie, Jeanne and Lehmann, Nathalie and Lochard, Camille and Montagne, R{\'e}mi and Myrodia, Vasiliki and Opuu, Vaitea and Parey, Elise and Polit, L{\'e}lia and Priv{\'e}, Sylvain and Quignot, Chlo{\'e} and Ruiz-Cuevas, Maria and Sissoko, Mariam and Sompairac, Nicolas and Vallerix, Audrey and Verrecchia, Violaine and Delarue, Marc and Gu{\'e}rois, Raphael and Ponty, Yann and S Sacquin-Mora and Carbone, Alessandra and Froidevaux, Christine and Le Crom, St{\'e}phane and Lespinet, Olivier and Weigt, Martin and Abboud, Samer and Bernardes, Juliana and Bouvier, Guillaume and Dequeker, Chlo{\'e} and Ferr{\'e}, Arnaud and Fuchs, Patrick and Lelandais, Ga{\"e}lle and Poulain, Pierre and Richard, Hugues and Schweke, Hugo and Laine, Elodie and Lopes, Anne} } @article {2018|2129, title = {Probing the quality control mechanism of the twin-arginine translocase with folding variants of a -designed heme protein.}, journal = {J Biol Chem}, volume = {293}, year = {2018}, month = {2018 05 04}, pages = {6672-6681}, abstract = {

Protein transport across the cytoplasmic membrane of bacterial cells is mediated by either the general secretion (Sec) system or the twin-arginine translocase (Tat). The Tat machinery exports folded and cofactor-containing proteins from the cytoplasm to the periplasm by using the transmembrane proton motive force as a source of energy. The Tat apparatus apparently senses the folded state of its protein substrates, a quality-control mechanism that prevents premature export of nascent unfolded or misfolded polypeptides, but its mechanistic basis has not yet been determined. Here, we investigated the innate ability of the model Tat system to recognize and translocate -designed protein substrates with experimentally determined differences in the extent of folding. Water-soluble, four-helix bundle maquette proteins were engineered to bind two, one, or no heme cofactors, resulting in a concomitant reduction in the extent of their folding, assessed with temperature-dependent CD spectroscopy and one-dimensional H NMR spectroscopy. Fusion of the archetypal N-terminal Tat signal peptide of the trimethylamine--oxide (TMAO) reductase (TorA) to the N terminus of the protein maquettes was sufficient for the Tat system to recognize them as substrates. The clear correlation between the level of Tat-dependent export and the degree of heme -induced folding of the maquette protein suggested that the membrane-bound Tat machinery can sense the extent of folding and conformational flexibility of its substrates. We propose that these artificial proteins are ideal substrates for future investigations of the Tat system\&$\#$39;s quality-control mechanism.

}, keywords = {Amino Acid Sequence, Bacterial Proteins, Circular Dichroism, Escherichia coli, Escherichia coli Proteins, Heme-Binding Proteins, Hemeproteins, Membrane Transport Proteins, Methylamines, Models, Molecular, Oxidoreductases, N-Demethylating, Periplasm, Protein Folding, Protein Sorting Signals, Protein Stability, Protein Transport, Proton Magnetic Resonance Spectroscopy, Substrate Specificity, Temperature}, issn = {1083-351X}, doi = {10.1074/jbc.RA117.000880}, author = {Sutherland, George A and Grayson, Katie J and Adams, Nathan B P and Mermans, Daphne M J and Jones, Alexander S and Robertson, Angus J and Auman, Dirk B and Brindley, Amanda A and Sterpone, Fabio and Tuffery, Pierre and Philippe Derreumaux and Dutton, P Leslie and Robinson, Colin and Hitchcock, Andrew and Hunter, C Neil} } @article {2017|2033, title = {Configurational Disorder of Water Hydrogen Bond Network at the Protein Dynamical Transition}, volume = {121}, year = {2017}, pages = {6792-6798}, author = {O. Rahaman and M. Kalimeri and M. Katava and A. Paciaroni and F. Sterpone} } @article {2017, title = {Mobility and core-protein binding patterns of disordered C-terminal tails in β-tubulin isotypes.}, journal = {Biochemistry}, volume = { 56}, year = {2017}, pages = {1746{\textendash}1756}, chapter = {1746}, abstract = {

Although they play a significant part in the regulation of microtubule structure, dynamics and function, the disordered C-terminal tails of tubulin remain invisible to experimental structural methods and do not appear in the crystallographic structures that are currently available in the Protein Data Bank. Interestingly, these tails concentrate most of the sequence variability between tubulin isotypes, and are the sites of the principal post-translational modifications undergone by this protein. Using homology modeling, we developed two complete models for the human αI/βI and αI/βIII tubulin isotypes that include their C-terminal tails. We then investigated the conformational variability of the two β-tails using long time-scale classical Molecular Dynamics (MD) simulations that revealed similar features, notably the unexpected presence of common anchoring regions on the surface of the tubulin dimer, but also distinctive mobility or interaction patterns, some of which could be related to the tail lengths and charge distributions. We also observed in our simulations that the C-terminal tail from the βI isotype, but not the βIII, formed contacts in the putative binding site of a recently discovered peptide that disrupts microtubule formation in glioma cells. Hindering the binding site in the βI isotype would be consistent with this peptide\’s preferential disruption of microtubule formation in glioma, whose cells overexpress βIII, compared to normal glial cells. While these observations need to be confirmed with more intensive sampling, our study opens up new perspectives for the development of isotype-specific chemotherapy drugs.

}, doi = {10.1021/acs.biochem.6b00988}, author = {Laurin, Yoann and Eyer, Joel and Charles H. Robert and Chantal Pr{\'e}vost and S Sacquin-Mora} } @conference {2017|2101, title = {Molecular Visualization of Computational Biology Data: A Survey of Surveys}, booktitle = {EuroVis 2017 - Short Papers}, year = {2017}, publisher = {The Eurographics Association}, organization = {The Eurographics Association}, isbn = {978-3-03868-043-7}, doi = {10.2312/eurovisshort.20171146}, author = {Alharbi, Naif and Alharbi, Mohammad and Martinez, Xavier and Krone, Michael and Rose, Alexander S. and Marc Baaden and Laramee, Robert S. and Chavent, Matthieu}, editor = {Barbora Kozlikova and Tobias Schreck and Thomas Wischgoll} } @article {2017|2028, title = {New Coarse Variables for the Accurate Determination of Standard Binding Free Energies}, journal = {J Chem Theory Comput}, volume = {13}, year = {2017}, month = {2017 Nov 14}, pages = {5173-5178}, abstract = {

To improve sampling of the configurational entropy change upon protein-ligand binding, we have introduced a new set of coarse variables describing the relative orientation and position of the ligand via a global macromolecular orientational procedure, onto which geometrical restraints are applied. Evaluating the potential of mean force for the different coarse variables, the experimental standard binding free energy for three decapeptides associated with the SH3 domain of the Abl kinase is reproduced quantitatively.

}, issn = {1549-9626}, doi = {10.1021/acs.jctc.7b00791}, author = {Fu, Haohao and Cai, Wensheng and J{\'e}r{\^o}me H{\'e}nin and Roux, Beno{\^\i}t and Chipot, Christophe} } @article {2017|2036, title = {VLITL is a major cross-β-sheet signal for fibrinogen Aα-chain frameshift variants.}, journal = {Blood}, volume = {130}, year = {2017}, month = {2017 12 21}, pages = {2799-2807}, abstract = {

The first case of hereditary fibrinogen Aα-chain amyloidosis was recognized \>20 years ago, but disease mechanisms still remain unknown. Here we report detailed clinical and proteomics studies of a French kindred with a novel amyloidogenic fibrinogen Aα-chain frameshift variant, Phe521Leufs, causing a severe familial form of renal amyloidosis. Next, we focused our investigations to elucidate the molecular basis that render this Aα-chain variant amyloidogenic. We show that a 49-mer peptide derived from the C-terminal part of the Phe521Leufs chain is deposited as fibrils in the patient\&$\#$39;s kidneys, establishing that only a small portion of Phe521Leufs directly contributes to amyloid formation in vivo. In silico analysis indicated that this 49-mer Aα-chain peptide contained a motif (VLITL), with a high intrinsic propensity for β-aggregation at residues 44 to 48 of human renal fibrils. To experimentally verify the amyloid propensity of VLITL, we generated synthetic Phe521Leufs-derived peptides and compared their capacity for fibril formation in vitro with that of their VLITL-deleted counterparts. We show that VLITL forms typical amyloid fibrils in vitro and is a major signal for cross-β-sheet self-association of the 49-mer Phe521Leufs peptide identified in vivo, whereas its absence abrogates fibril formation. This study provides compelling evidence that VLITL confers amyloidogenic properties to Aα-chain frameshift variants, yielding a previously unknown molecular basis for the pathogenesis of Aα-chain amyloidosis.

}, keywords = {Amino Acid Motifs, Amino Acid Sequence, Amyloid, Amyloidosis, Familial, Fibrinogen, Frameshift Mutation, Humans, Kidney, Protein Conformation, beta-Strand}, issn = {1528-0020}, doi = {10.1182/blood-2017-07-796185}, author = {Garnier, Cyrille and Briki, Fatma and Nedelec, Brigitte and Le Pogamp, Patrick and Dogan, Ahmet and Rioux-Leclercq, Nathalie and Goude, Renan and Beugnet, Caroline and Martin, Laurent and Delpech, Marc and Bridoux, Frank and Grateau, Gilles and Doucet, Jean and Philippe Derreumaux and Valleix, Sophie} } @article {2016|1661, title = {Hybridizing Rapidly Exploring Random Trees and Basin Hopping Yields an Improved Exploration of Energy Landscapes}, journal = {J. Comput. Chem.}, volume = {37}, year = {2016}, month = {mar}, pages = {752}, chapter = {739}, abstract = {

The number of local minima of the potential energy landscape (PEL) of molecular systems generally grows exponentially with the number of degrees of freedom, so that a crucial property of PEL exploration algorithms is their ability to identify local minima, which are low lying and diverse. In this work, we pres- ent a new exploration algorithm, retaining the ability of basin hopping (BH) to identify local minima, and that of transition based rapidly exploring random trees (T-RRT) to foster the exploration of yet unexplored regions. This ability is obtained by interleaving calls to the extension procedures of BH and T- RRT, and we show tuning the balance between these two types of calls allows the algorithm to focus on low lying regions. Computational efficiency is obtained using state-of- the art data structures, in particular for searching approximate nearest neighbors in metric spaces. We present results for the BLN69, a protein model whose conformational space has dimension 207 and whose PEL has been studied exhaustively. On this system, we show that the propensity of our algorithm to explore low lying regions of the landscape significantly out- performs those of BH and T-RRT.

}, doi = {10.1002/jcc.24256}, author = {Christine A. Roth and Tom Dreyfus and Charles H. Robert and Fr{\'e}d{\'e}ric Cazals} } @article {2016|1750, title = {Non-equivalent binding sites for Abeta1-40 on PrP determine the oligomerisation pathway}, journal = {Prion}, volume = {10}, number = {1}, year = {2016}, pages = {S40}, issn = {1933-6896}, author = {Grznarova, Katarina and Torrent, Joan and Munoz-Montesino, Carola and Nasica, Jessica and Philippe Derreumaux and Beringue, Vincent and Deslys, Jean-Philippe and Rezaei, Human} } @article {2016|1733, title = {PEP-FOLD3: faster denovo structure prediction for linear peptides in solution and in complex}, journal = {Nucleic Acids Res.}, volume = {44}, number = {W1}, year = {2016}, pages = {W449-W454}, abstract = {Structure determination of linear peptides of 5-50 amino acids in aqueous solution and interacting with proteins is a key aspect in structural biology. PEP-FOLD3 is a novel computational framework, that allows both (i) de novo free or biased prediction for linear peptides between 5 and 50 amino acids, and (ii) the generation of native-like conformations of peptides interacting with a protein when the interaction site is known in advance. PEP-FOLD3 is fast, and usually returns solutions in a few minutes. Testing PEP-FOLD3 on 56 peptides in aqueous solution led to experimental-like conformations for 80\% of the targets. Using a benchmark of 61 peptide-protein targets starting from the unbound form of the protein receptor, PEP-FOLD3 was able to generate peptide poses deviating on average by 3.3 angstrom from the experimental conformation and return a native-like pose in the first 10 clusters for 52\% of the targets. PEP-FOLD3 is available at http://bioserv.rpbs.univ-paris-diderot.fr/services/PEP-FOLD3.}, issn = {0305-1048}, doi = {10.1093/nar/gkw329}, author = {Lamiable, Alexis and Thevenet, Pierre and Rey, Julien and Vavrusa, Marek and Philippe Derreumaux and Pierre Tuffery} } @article {2016|1744, title = {Picosecond infrared laser-induced all-atom nonequilibrium molecular dynamics simulation of dissociation of viruses}, journal = {Phys. Chem. Chem. Phys.}, volume = {18}, number = {17}, year = {2016}, month = {may}, pages = {11951{\textendash}11958}, abstract = {Since the discovery of the plant pathogen tobacco mosaic virus as the first viral entity in the late 1800s, viruses traditionally have been mainly thought of as pathogens for disease-resistances. However, viruses have recently been exploited as nanoplatforms with applications in biomedicine and materials science. To this aim, a large majority of current methods and tools have been developed to improve the physical stability of viral particles, which may be critical to the extreme physical or chemical conditions that viruses may encounter during purification, fabrication processes, storage and use. However, considerably fewer studies are devoted to developing efficient methods to degrade or recycle such enhanced stability biomaterials. With this in mind, we carry out all-atom nonequilibriummolecular dynamics simulation, inspired by the recently developed mid-infrared free-electron laser pulse technology, to dissociate viruses. Adopting the poliovirus as a representative example, we find that the primary step in the dissociation process is due to the strong resonance between the amide I vibrational modes of the virus and the tuned laser frequencies. This process is determined by a balance between the formation and dissociation of the protein shell, reflecting the highly plasticity of the virus. Furthermore, our method should provide a feasible approach to simulate viruses, which is otherwise too expensive for conventional equilibrium all-atom simulations of such very large systems. Our work shows a proof of concept which may open a new, efficient way to cleave or to recycle virus-based materials, provide an extremely valuable tool for elucidating mechanical aspects of viruses, and may well play an important role in future fighting against virus-related diseases.}, issn = {1463-9076}, doi = {10.1039/c5cp07711g}, author = {Viet Hoang Man and Van-Oanh, Nguyen-Thi and Philippe Derreumaux and Li, Mai Suan and Roland, Christopher and Sagui, Celeste and Phuong Hoang Nguyen} } @article {2015|1634, title = {Amyloid beta Protein and Alzheimer{\textquoteright}s Disease: When Computer Simulations Complement Experimental Studies}, journal = {Chem. Rev.}, volume = {115}, number = {9}, year = {2015}, month = {may}, pages = {3518{\textendash}3563}, doi = {10.1021/cr500638n}, author = {Nasica-Labouze, Jessica and Phuong Hoang Nguyen and Fabio Sterpone and Berthoumieu, Olivia and Buchete, Nicolae-Viorel and Cote, Sebastien and De Simone, Alfonso and Doig, Andrew J. and Faller, Peter and Garcia, Angel and Laio, Alessandro and Li, Mai Suan and Melchionna, Simone and Mousseau, Normand and Mu, Yuguang and Paravastu, Anant and Pasquali, Samuela and Rosenman, David J. and Strodel, Birgit and Tarus, Bogdan and Viles, John H. and Zhang, Tong and Wang, Chunyu and Philippe Derreumaux} } @article {2015|1657, title = {Changes in protein structure at the interface accompanying complex formation.}, journal = {Iucrj}, volume = {2}, number = {Pt 6}, year = {2015}, month = {nov}, pages = {643{\textendash}652}, publisher = {Department of Biochemistry, Bose Institute , P-1/12 CIT Scheme VIIM, Kolkata 700 054, India.}, abstract = {Protein interactions are essential in all biological processes. The changes brought about in the structure when a free component forms a complex with another molecule need to be characterized for a proper understanding of molecular recognition as well as for the successful implementation of docking algorithms. Here, unbound (U) and bound (B) forms of protein structures from the Protein-Protein Interaction Affinity Database are compared in order to enumerate the changes that occur at the interface atoms/residues in terms of the solvent-accessible surface area (ASA), secondary structure, temperature factors (B factors) and disorder-to-order transitions. It is found that the interface atoms optimize contacts with the atoms in the partner protein, which leads to an increase in their ASA in the bound interface in the majority (69\%) of the proteins when compared with the unbound interface, and this is independent of the root-mean-square deviation between the U and B forms. Changes in secondary structure during the transition indicate a likely extension of helices and strands at the expense of turns and coils. A reduction in flexibility during complex formation is reflected in the decrease in B factors of the interface residues on going from the U form to the B form. There is, however, no distinction in flexibility between the interface and the surface in the monomeric structure, thereby highlighting the potential problem of using B factors for the prediction of binding sites in the unbound form for docking another protein. 16\% of the proteins have missing (disordered) residues in the U form which are observed (ordered) in the B form, mostly with an irregular conformation; the data set also shows differences in the composition of interface and non-interface residues in the disordered polypeptide segments as well as differences in their surface burial.}, doi = {10.1107/S2052252515015250}, author = {Chakravarty, Devlina and Janin, Jo{\"e}l and Charles H. Robert and Chakrabarti, Pinak} } @article {2015|1635, title = {Combined Experimental and Simulation Studies Suggest a Revised Mode of Action of the Anti-Alzheimer Disease Drug NQ-Trp}, journal = {Chemistry-a European Journal}, volume = {21}, number = {36}, year = {2015}, pages = {12657{\textendash}12666}, doi = {10.1002/chem.201500888}, author = {Berthoumieu, Olivia and Phuong Hoang Nguyen and del Castillo-Frias, Maria P. and Ferre, Sabrina and Tarus, Bogdan and Nasica-Labouze, Jessica and Noel, Sabrina and Saurel, Olivier and Rampon, Claire and Doig, Andrew J. and Philippe Derreumaux and Faller, Peter} } @article {2015|1679, title = {Conformational ensembles and sampled landscapes: analysis and comparison}, journal = {J. Comp. Chem.}, volume = {36}, year = {2015}, pages = {1213{\textendash}31}, author = {Fr{\'e}d{\'e}ric Cazals and A Roth and T Dreyfus and D Mazauric and Charles H. Robert} } @article {2015|1965, title = {An integrative approach to the study of filamentous oligomeric assemblies, with application to {R}ec{A}}, journal = {Plos One}, volume = {in press}, year = {2015}, pages = {e0116414}, abstract = {

Oligomeric macromolecules in the cell self-organize into a wide variety of geometrical motifs such as helices, rings or linear filaments. The recombinase proteins involved in homologous recombination present many such assembly motifs. Here, we examine in particular the polymorphic characteristics of RecA, the most studied member of the recombinase family, using an integrative approach that relates local modes of monomer/monomer association to the global architecture of their screw-type organization. In our approach, local modes of association are sampled via docking or Monte Carlo simulations. This enables shedding new light on fiber morphologies that may be adopted by the RecA protein. Two distinct RecA helical morphologies, the so-called \"extended\" and \"compressed\" forms, are known to play a role in homologous recombination. We investigate the variability within each form in terms of helical parameters and steric accessibility. We also address possible helical discontinuities in RecA filaments due to multiple monomer-monomer association modes. By relating local interface organization to global filament morphology, the strategies developed here to study RecA self-assembly are particularly well suited to other DNA-binding proteins and to filamentous protein assemblies in general.

}, doi = {10.1371/journal.pone.0116414}, author = {Benjamin Boyer and Johann Ezelin and Pierre Poulain and A Saladin and Martin Zacharias and Charles H. Robert and Chantal Pr{\'e}vost} } @article {2015|1586, title = {Investigating the Structural Variability and Binding Modes of the Glioma Targeting NFL-TBS.40-63 Peptide on Tubulin}, journal = {Biochemistry}, volume = {54}, number = {23}, year = {2015}, month = {jun}, pages = {3660{\textendash}3669}, doi = {10.1021/acs.biochem5b00146}, author = {Laurin, Y. and Savarin, P. and Charles H. Robert and M. Takahashi and Eyer, J. and Chantal Pr{\'e}vost and S Sacquin-Mora} } @article {2015|1664, title = {Membrane Protein Structure, Function, and Dynamics: a Perspective from Experiments and Theory.}, journal = {J. Membr. Biol.}, volume = {248}, year = {2015}, publisher = {Biomedical Research Foundation, Academy of Athens, 4 Soranou Ephessiou, 11527, Athens, Greece, zcournia@bioacademy.gr.}, chapter = {611}, abstract = {

Membrane proteins mediate processes that are fundamental for the flourishing of biological cells. Membrane-embedded transporters move ions and larger solutes across membranes; receptors mediate communication between the cell and its environment and membrane-embedded enzymes catalyze chemical reactions. Understanding these mechanisms of action requires knowledge of how the proteins couple to their fluid, hydrated lipid membrane environment. We present here current studies in computational and experimental membrane protein biophysics, and show how they address outstanding challenges in understanding the complex environmental effects on the structure, function, and dynamics of membrane proteins.

}, doi = {10.1007/s00232-015-9802-0}, author = {Cournia, Zoe and Allen, Toby W. and Andricioaei, Ioan and Antonny, Bruno and Baum, Daniel and Grace Brannigan and Buchete, Nicolae-Viorel and Deckman, Jason T. and Delemotte, Lucie and Del Val, Coral and Friedman, Ran and Gkeka, Paraskevi and Hege, Hans-Christian and J{\'e}r{\^o}me H{\'e}nin and Kasimova, Marina A. and Kolocouris, Antonios and Michael L Klein and Khalid, Syma and Lemieux, M Joanne and Lindow, Norbert and Roy, Mahua and Selent, Jana and Mounir Tarek and Tofoleanu, Florentina and Vanni, Stefano and Urban, Sinisa and Wales, David J. and Smith, Jeremy C. and Bondar, Ana-Nicoleta} } @article {2015|1549, title = {{N}othing to sneeze at: a dynamic and integrative computational model of an influenza {A} virion}, journal = {Structure}, volume = {23}, number = {3}, year = {2015}, month = {mar}, pages = {584{\textendash}597}, author = {Reddy, T. and Shorthouse, D. and Parton, D. L. and Jefferys, E. and Fowler, P. W. and Matthieu Chavent and Marc Baaden and Sansom, M. S.} } @article {2015|1705, title = {Picosecond dissociation of amyloid fibrils with infrared laser: A nonequilibrium simulation study}, journal = {J. Chem. Phys.}, volume = {143}, number = {15}, year = {2015}, month = {oct}, pages = {155101}, doi = {10.1063/1.4933207}, author = {Man Hoang Viet and Philippe Derreumaux and Mai Suan Li and Roland, Christopher and Sagui, Celeste and Phuong Hoang Nguyen} } @article {2015|1745, title = {Picosecond melting of peptide nanotubes using an infrared laser: a nonequilibrium simulation study}, journal = {Phys. Chem. Chem. Phys.}, volume = {17}, number = {41}, year = {2015}, pages = {27275{\textendash}27280}, doi = {10.1039/c5cp04401d}, author = {Viet, Man Hoang and Phan Minh Truong and Philippe Derreumaux and Li, Mai Suan and Roland, Christopher and Sagui, Celeste and Phuong Hoang Nguyen} } @article {2015|1668, title = {Role of Internal Water on Protein Thermal Stability: The Case of Homologous G Domains.}, journal = {J. Phys. Chem. B}, volume = {119}, year = {2015}, month = {jul}, pages = {8939{\textendash}49}, abstract = {

In this work, we address the question of whether the enhanced stability of thermophilic proteins has a direct connection with internal hydration. Our model systems are two homologous G domains of different stability: the mesophilic G domain of the elongation factor thermal unstable protein from E. coli and the hyperthermophilic G domain of the EF-1α protein from S. solfataricus. Using molecular dynamics simulation at the microsecond time scale, we show that both proteins host water molecules in internal cavities and that these molecules exchange with the external solution in the nanosecond time scale. The hydration free energy of these sites evaluated via extensive calculations is found to be favorable for both systems, with the hyperthermophilic protein offering a slightly more favorable environment to host water molecules. We estimate that, under ambient conditions, the free energy gain due to internal hydration is about 1.3 kcal/mol in favor of the hyperthermophilic variant. However, we also find that, at the high working temperature of the hyperthermophile, the cavities are rather dehydrated, meaning that under extreme conditions other molecular factors secure the stability of the protein. Interestingly, we detect a clear correlation between the hydration of internal cavities and the protein conformational landscape. The emerging picture is that internal hydration is an effective observable to probe the conformational landscape of proteins. In the specific context of our investigation, the analysis confirms that the hyperthermophilic G domain is characterized by multiple states and it has a more flexible structure than its mesophilic homologue.

}, issn = {1520-5207}, doi = {10.1021/jp507571u}, author = {Rahaman, Obaidur and Kalimeri, Maria and Melchionna, Simone and J{\'e}r{\^o}me H{\'e}nin and Fabio Sterpone} } @article {2015|2000, title = {{T}he plastid terminal oxidase: its elusive function points to multiple contributions to plastid physiology}, journal = {Annu. Rev. Plant Biol.}, volume = {66}, number = {1}, year = {2015}, pages = {49{\textendash}74}, publisher = {Annual Reviews}, author = {Nawrocki, W. J. and Tourasse, N. J. and Antoine Taly and Rappaport, F. and Wollman, F. A.} } @article {2014|1931, title = {Assessing the effect of dynamics on the closed-loop protein-folding hypothesis}, journal = {Journal of the Royal Society Interface}, volume = {11}, number = {91}, year = {2014}, pages = {20130935}, doi = {10.1098/rsif.2013.0935}, url = {http://rsif.royalsocietypublishing.org/content/11/91/20130935.abstract}, author = {Chintapalli, Sree V. and Illingworth, Christopher J. R. and Upton, Graham J. G. and S Sacquin-Mora and Reeves, Philip J. and Mohammedali, Hani S. and Reynolds, Christopher A.} } @article {2014|1412, title = {{E}xa{V}iz: a flexible framework to analyse, steer and interact with molecular dynamics simulations}, journal = {Faraday Discuss.}, volume = {169}, year = {2014}, note = {[DOI:\href{http://dx.doi.org/10.1039/c3fd00142c}{10.1039/c3fd00142c}] [PubMed:\href{http://www.ncbi.nlm.nih.gov/pubmed/25340956}{25340956}]}, pages = {119{\textendash}142}, author = {Dreher, M and Prevoteau-Jonquet, J and Trellet, M and Piuzzi, M and Marc Baaden and Raffin, B and Nicolas F{\'e}rey and Robert, S and Limet, S.} } @article {2014|1772, title = {INRIA Tech Report: Conformational ensembles and sampled landscapes: analysis and comparison.}, year = {2014}, author = {Fr{\'e}d{\'e}ric Cazals and T. Dreyfus and D. Mazauric and A. Roth and Charles H. Robert} } @conference {2014|1760, title = {Optogating a powerful approach to control an ion-channel gate}, booktitle = {PURINERGIC SIGNALLING}, volume = {10}, number = {4}, year = {2014}, pages = {762{\textendash}762}, publisher = {SPRINGER VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS}, organization = {SPRINGER VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS}, author = {Lemoine, Damien and Habermacher, Chlo{\'e} and Martz, Adeline and M{\'e}ry, Pierre-Fran\c cois and Bouquier, Nathalie and Diverchy, Fanny and Antoine Taly and Rassendren, Fran\c cois and Specht, Alexandre and Grutter, Thomas} } @article {2013|1956, title = {The effect of protein composition on hydration dynamics}, journal = {Phys. Chem. Chem. Phys.}, volume = {15}, number = {10}, year = {2013}, pages = {3570{\textendash}3576}, publisher = {The Royal Society of Chemistry}, abstract = {Water dynamics at the surface of two homologous proteins with different thermal resistances is found to be unaffected by the different underlying amino-acid compositions{,} and when proteins are folded it responds similarly to temperature variations. Upon unfolding the water dynamics slowdown with respect to bulk decreases by a factor of two. Our findings are explained by the dominant topological perturbation induced by the protein on the water hydrogen bond dynamics.}, author = {Rahaman, O. and Melchionna, S. and Laage, D. and Sterpone, F.} } @article {2013|1926, title = {How Conformational Flexibility Stabilizes the Hyperthermophilic Elongation Factor G-Domain}, journal = {J. Phys. Chem. B}, volume = {117}, number = {44}, year = {2013}, month = {nov}, pages = {13775{\textendash}13785}, author = {Kalimeri, Maria and Rahaman, Obaidur and Melchionna, Simone and Sterpone, Fabio} } @article {2013|1531, title = {Interactive Molecular Dynamics: Scaling up to Large Systems.}, journal = {Procedia Comput. Sci.}, volume = {18}, year = {2013}, pages = {20{\textendash}29}, doi = {10.1016/j.procs.2013.05.165}, author = {M. Dreher and M. Piuzzi and A. Turki and Matthieu Chavent and Marc Baaden and Nicolas F{\'e}rey and S. Limet and B. Raffin and S. Robert} } @inbook {2013|1499, title = {Modeling macromolecular complexes: a journey across scales}, booktitle = {Modeling in Computational Biology and Biomedicine: A Multidisciplinary Endeavor}, year = {2013}, note = {(in press)}, publisher = {Springer-Verlag Berlin Heidelberg}, organization = {Springer-Verlag Berlin Heidelberg}, author = {Fr{\'e}d{\'e}ric Cazals and Tom Dreyfus and Charles H. Robert} } @article {2013|1747, title = {A mutation causes MuSK reduced sensitivity to agrin and congenital myasthenia}, journal = {Plos One}, volume = {8}, number = {1}, year = {2013}, publisher = {Public Library of Science}, author = {Ammar, A Ben and Soltanzadeh, Payam and Bauch{\'e}, St{\'e}phanie and Richard, Pascale and Goillot, Evelyne and Herbst, Ruth and Gaudon, Karen and Huz{\'e}, Caroline and Schaeffer, Laurent and Yamanashi, Yuji and others} } @article {2013|1973, title = {{O}ptical control of an ion channel gate}, journal = {Proc. Natl. Acad. Sci. U.s.a.}, volume = {110}, number = {51}, year = {2013}, month = {dec}, pages = {20813{\textendash}20818}, author = {Lemoine, D. and Habermacher, C. and Martz, A. and Mery, P. F. and Bouquier, N. and Diverchy, F. and Antoine Taly and Rassendren, F. and Specht, A. and Grutter, T.} } @article {2013|1976, title = {Reassessing buried surface areas in protein-protein complexes.}, journal = {Protein Sci.}, volume = {22}, year = {2013}, month = {aug}, pages = {1453{\textendash}57}, abstract = {

The buried surface area (BSA), which measures the size of the interface in a protein-protein complex may differ from the accessible surface area (ASA) lost upon association (which we call DSA), if conformation changes take place. To evaluate the DSA, we measure the ASA of the interface atoms in the bound and unbound states of the components of 144 protein-protein complexes taken from the Protein-Protein Interaction Affinity Database of Kastritis et al. (2011). We observe differences exceeding 20\%, and a systematic bias in the distribution. On average, the ASA calculated in the bound state of the components is 3.3\% greater than in their unbound state, and the BSA, 7\% greater than the DSA. The bias is observed even in complexes where the conformation changes are small. An examination of the bound and unbound structures points to a possible origin: local movements optimize contacts with the other component at the cost of internal contacts, and presumably also the binding free energy.

}, keywords = {binding free energy, conformation changes, protein-protein interaction, solvent accessible surface}, doi = {10.1002/pro.2330}, author = {Chakravarty, Devlina and Guharoy, Mainak and Robert, Charles H. and Chakrabarti, Pinak and Janin, Jo{\"e}l} } @article {2013|1814, title = {Towards Morse theory for point cloud data.}, journal = {Inria Tech Reports}, number = {8331}, year = {2013}, publisher = {Inria}, url = {http://hal.inria.fr/hal-00848753}, author = {F. Cazals and C. Mueller and C. Robert and A. Roth} } @article {2012|1756, title = {Involvement of the cysteine-rich head domain in activation and desensitization of the P2X1 receptor}, journal = {Proceedings of the National Academy of Sciences of the United States of America}, volume = {109}, number = {28}, year = {2012}, pages = {11396{\textendash}11401}, publisher = {National Acad Sciences}, author = {L{\"o}rinczi, {\'E}va and Bhargava, Yogesh and Marino, Stephen F and Antoine Taly and Kaczmarek-H{\'a}jek, Karina and Barrantes-Freer, Alonso and Dutertre, S{\'e}bastien and Grutter, Thomas and Rettinger, J{\"u}rgen and Nicke, Annette} } @article {2012|1813, title = {Substitutions at residue 211 in the prion protein drive a switch between CJD and GSS syndrome, a new mechanism governing inherited neurodegenerative disorders}, journal = {Hum. Mol. Genet.}, volume = {21}, number = {26}, year = {2012}, month = {dec}, pages = {5417{\textendash}5428}, doi = {10.1093/hmg/dds377}, author = {Katell Peoc{\textquoteright}h and Etienne Levavasseur and Emilien Delmont and Alfonso De Simone Isabelle Laffont-Proust and Nicolas Privat and Y Chebaro and C{\'e}line Chapuis Pierre Bedoucha and Jean-Philippe Brandel and Annie Laquerriere and Jean-Louis Kemeny Jean-Jacques Hauw and Michel Borg and Human Rezaei and Philippe Derreumaux Jean-Louis Laplanche and St{\'e}phane Ha{\"\i}k} } @article {2012|2005, title = {α7-{N}icotinic acetylcholine receptors: an old actor for new different roles}, journal = {Curr. Drug Targets}, volume = {13}, number = {5}, year = {2012}, month = {may}, pages = {574{\textendash}578}, publisher = {Bentham Science Publishers}, author = {Russo, P. and Antoine Taly} } @article {2011|1834, title = {{B}inding modes of noncompetitive {G}{A}{B}{A}-channel blockers revisited using engineered affinity-labeling reactions combined with new docking studies}, journal = {J. Agric. Food Chem.}, volume = {59}, number = {7}, year = {2011}, month = {apr}, pages = {2803{\textendash}2807}, author = {Charon, S. and Antoine Taly and Rodrigo, J. and Perret, P. and Goeldner, M.} } @article {2011|1665, title = {Community-wide assessment of protein-interface modeling suggests improvements to design methodology.}, journal = {J. Mol. Biol.}, volume = {414}, year = {2011}, month = {nov}, pages = {289{\textendash}302}, abstract = {

The CAPRI (Critical Assessment of Predicted Interactions) and CASP (Critical Assessment of protein Structure Prediction) experiments have demonstrated the power of community-wide tests of methodology in assessing the current state of the art and spurring progress in the very challenging areas of protein docking and structure prediction. We sought to bring the power of community-wide experiments to bear on a very challenging protein design problem that provides a complementary but equally fundamental test of current understanding of protein-binding thermodynamics. We have generated a number of designed protein-protein interfaces with very favorable computed binding energies but which do not appear to be formed in experiments, suggesting that there may be important physical chemistry missing in the energy calculations. A total of 28 research groups took up the challenge of determining what is missing: we provided structures of 87 designed complexes and 120 naturally occurring complexes and asked participants to identify energetic contributions and/or structural features that distinguish between the two sets. The community found that electrostatics and solvation terms partially distinguish the designs from the natural complexes, largely due to the nonpolar character of the designed interactions. Beyond this polarity difference, the community found that the designed binding surfaces were, on average, structurally less embedded in the designed monomers, suggesting that backbone conformational rigidity at the designed surface is important for realization of the designed function. These results can be used to improve computational design strategies, but there is still much to be learned; for example, one designed complex, which does form in experiments, was classified by all metrics as a nonbinder.

}, keywords = {Binding Sites, Models, Molecular, Protein Binding, Proteins}, issn = {1089-8638}, doi = {10.1016/j.jmb.2011.09.031}, author = {Fleishman, Sarel J and Whitehead, Timothy A and Strauch, Eva-Maria and Corn, Jacob E and Qin, Sanbo and Zhou, Huan-Xiang and Mitchell, Julie C and Demerdash, Omar N A and Takeda-Shitaka, Mayuko and Terashi, Genki and Moal, Iain H and Li, Xiaofan and Bates, Paul A and Martin Zacharias and Park, Hahnbeom and Ko, Jun-su and Lee, Hasup and Seok, Chaok and Bourquard, Thomas and Bernauer, Julie and Poupon, Anne and Az{\'e}, J{\'e}r{\^o}me and Soner, Seren and Ovali, Sefik Kerem and Ozbek, Pemra and Tal, Nir Ben and Haliloglu, T{\"u}rkan and Hwang, Howook and Vreven, Thom and Pierce, Brian G and Weng, Zhiping and P{\'e}rez-Cano, Laura and Pons, Carles and Fern{\'a}ndez-Recio, Juan and Jiang, Fan and Yang, Feng and Gong, Xinqi and Cao, Libin and Xu, Xianjin and Liu, Bin and Wang, Panwen and Li, Chunhua and Wang, Cunxin and Charles H. Robert and Guharoy, Mainak and Liu, Shiyong and Huang, Yangyu and Li, Lin and Guo, Dachuan and Chen, Ying and Xiao, Yi and London, Nir and Itzhaki, Zohar and Schueler-Furman, Ora and Inbar, Yuval and Potapov, Vladimir and Cohen, Mati and Schreiber, Gideon and Tsuchiya, Yuko and Kanamori, Eiji and Standley, Daron M and Nakamura, Haruki and Kinoshita, Kengo and Driggers, Camden M and Hall, Robert G and Morgan, Jessica L and Hsu, Victor L and Zhan, Jian and Yang, Yuedong and Zhou, Yaoqi and Kastritis, Panagiotis L and Bonvin, Alexandre M J J and Zhang, Weiyi and Camacho, Carlos J and Kilambi, Krishna P and Sircar, Aroop and Gray, Jeffrey J and Ohue, Masahito and Uchikoga, Nobuyuki and Matsuzaki, Yuri and Ishida, Takashi and Akiyama, Yutaka and Khashan, Raed and Bush, Stephen and Fouches, Denis and Tropsha, Alexander and Esquivel-Rodr{\'\i}guez, Juan and Kihara, Daisuke and Stranges, P Benjamin and Jacak, Ron and Kuhlman, Brian and Huang, Sheng-You and Zou, Xiaoqin and Wodak, Shoshana J and Janin, Jo{\"e}l and Baker, David} } @inbook {2011|1573, title = {Exploring the energy landscape of small peptides and proteins by molecular dynamics simulations}, year = {2011}, publisher = {Wiley}, organization = {Wiley}, author = {G. Stock and A. Jain and L. Riccardi and Phuong Hoang Nguyen}, editor = {R. Schweitzer-Stenner} } @article {2011|1848, title = {Free energy profiles along consensus normal modes provide insight into {HIV}-1 protease flap opening}, journal = {J. Chem. Theor. Comput.}, volume = {7}, year = {2011}, pages = {2348{\textendash}52}, author = {Paulo R. Batista and Gaurav Pandey and Paulo M. Bisch and Paulo G. Pascutti and David Perahia and Charles H. Robert} } @article {2011|1437, title = {GPU-accelerated atom and dynamic bond visualization using HyperBalls: a unified algorithm for balls, sticks and hyperboloids}, journal = {J. Comput. Chem.}, volume = {32}, number = {13}, year = {2011}, month = {oct}, pages = {2924{\textendash}2935}, doi = {10.1002/jcc.21861/abstract}, author = {Matthieu Chavent and A. Vanel and A. Tek and B. L{\'e}vy and S. Robert and B. Raffin and Marc Baaden} } @article {2011|1738, title = {Non-monotonic dependence of water reorientation dynamics on surface hydrophilicity: competing effects of the hydration structure and hydrogen-bond strength}, journal = {Phys. Chem. Chem. Phys.}, volume = {13}, year = {2011}, pages = {19911}, abstract = {

The reorientation dynamics of interfacial water molecules was recently shown to change non-monotonically next to surfaces of increasing hydrophilicity, with slower dynamics next to strongly hydrophobic (apolar) and very hydrophilic surfaces, and faster dynamics next to surfaces of intermediate hydrophilicities. Through a combination of molecular dynamics simulations and analytic modeling, we provide a molecular interpretation of this behavior. We show that this non-monotonic dependence arises from two competing effects induced by the increasing surface hydrophilicity: first a change in the hydration structure with an enhanced population of water OH bonds pointing toward the surface and second a strengthening of the water-surface interaction energy. The extended jump model, including the effects due to transition-state excluded volume and transition-state hydrogen-bond strength, provides a quasi-quantitative description of the non-monotonic changes in the water reorientation dynamics with surface hydrophilicity.

}, issn = {1463-9076}, author = {Guillaume Stirnemann and Castrillon, Santiago Romero-Vargas and Hynes, James T. and Rossky, Peter J. and Debenedetti, Pablo G. and Laage, Damien} } @inbook {2011|1417, title = {Receptor Flexibility in Ligand Docking and Virtual Screening.}, booktitle = {In-silico lead discovery}, year = {2011}, publisher = {Bentham Science Publishers}, organization = {Bentham Science Publishers}, author = {Maria A. Miteva and Charles H. Robert and J. D. Marechal and David Perahia} } @article {2011|1383, title = {Reorientation and Allied Dynamics in Water and Aqueous Solutions}, journal = {Annu. Rev. Phys. Chem.}, volume = {62}, year = {2011}, pages = {395{\textendash}416}, abstract = {

The reorientation of a water molecule is important for a host of phenomena, ranging over?in an only partial listing?the key dynamic hydrogen-bond network restructuring of water itself, aqueous solution chemical reaction mechanisms and rates, ion transport in aqueous solution and membranes, protein folding, and enzymatic activity. This review focuses on water reorientation and related dynamics in pure water, and for aqueous solutes with hydrophobic, hydrophilic, and amphiphilic character, ranging from tetramethylurea to halide ions and amino acids. Attention is given to the application of theory, simulation, and experiment in the probing of these dynamics, in usefully describing them, and in assessing the description. Special emphasis is placed on a novel sudden, large-amplitude jump mechanism for water reorientation, which contrasts with the commonly assumed Debye rotational diffusion mechanism, characterized by small-amplitude angular motion. Some open questions and directions for further research are also discussed. Expected final online publication date for the Annual Review of Physical Chemistry Volume 62 is March 31, 2011. Please see http://www.annualreviews.org/catalog/pubdates.aspx for revised estimates.

}, isbn = {0066-426X 1545-1593}, issn = {0066-426X}, doi = {doi: 10.1146/annurev.physchem.012809.103503}, url = {http://www.annualreviews.org/doi/abs/10.1146/annurev.physchem.012809.103503$\backslash$nhttp://www.annualreviews.org.login.ezproxy.lib.purdue.edu/doi/pdf/10.1146/annurev.physchem.012809.103503}, author = {Laage, Damien and Guillaume Stirnemann and Fabio Sterpone and Rey, Rossend and Hynes, James T.} } @article {2010|1749, title = {A computational study of a recreated {G} protein-{GEF} reaction intermediate competent for nucleotide exchange: fate of the {M}g ion}, journal = {Plos One}, volume = {5}, number = {2}, year = {2010}, month = {feb}, pages = {e9142}, publisher = {Public Library of Science}, abstract = {

Small G-proteins of the superfamily Ras function as molecular switches, interacting with different cellular partners according to their activation state. G-protein activation involves the dissociation of bound GDP and its replacement by GTP, in an exchange reaction that is accelerated and regulated in the cell by guanine-nucleotide exchange factors (GEFs). Large conformational changes accompany the exchange reaction, and our understanding of the mechanism is correspondingly incomplete. However, much knowledge has been derived from structural studies of blocked or inactive mutant GEFs, which presumably closely represent intermediates in the exchange reaction and yet which are by design incompetent for carrying out the nucleotide exchange reaction. In this study we have used comparative modelling to recreate an exchange-competent form of a late, pre-GDP-ejection intermediate species in Arf1, a well-characterized small G-protein. We extensively characterized three distinct models of this intermediate using molecular dynamics simulations, allowing us to address ambiguities related to the mutant structural studies. We observed in particular the unfavorable nature of Mg2+ associated forms of the complex and the establishment of closer Arf1-GEF contacts in its absence. The results of this study shed light on GEF-mediated activation of this small G protein and on predicting the fate of the Mg ion at a critical point in the exchange reaction. The structural models themselves furnish additional targets for interfacial inhibitor design, a promising direction for exploring potentially druggable targets with high biological specificity.

}, doi = {10.1371/journal.pone.0009142}, url = {http://dx.doi.org/10.1371\%2Fjournal.pone.0009142}, author = {M{\'e}riam Ben Hamida{\textendash}Reba\"{\i} and Charles H. Robert} } @article {2010|1736, title = {Consensus {M}odes, a robust description of protein collective motions from multiple-minima normal mode analysis{\textendash}application to the {HIV}-1 protease.}, journal = {Phys. Chem. Chem. Phys.}, volume = {12}, year = {2010}, month = {mar}, pages = {2850{\textendash}2859}, abstract = {

Protein flexibility is essential for enzymatic function, ligand binding, and protein-protein or protein-nucleic acid interactions. Normal mode analysis has increasingly been shown to be well suited for studying such flexibility, as it can be used to identify favorable structural deformations that correspond to functional motions. However, normal modes are strictly relevant to a single structure, reflecting a particular minimum on a complex energy surface, and are thus susceptible to artifacts. We describe a new theoretical framework for determining \"consensus\" normal modes from a set of related structures, such as those issuing from a short molecular dynamics simulation. This approach is more robust than standard normal mode analysis, and provides higher collectivity and symmetry properties. In an application to HIV-1 protease, the low-frequency consensus modes describe biologically relevant motions including flap opening and closing that can be used in interpreting structural changes accompanying the binding of widely differing inhibitors.

}, doi = {10.1039/b919148h}, author = {Paulo R. Batista and Charles H. Robert and Jean-Didier Mar{\'e}chal and M{\'e}riam Ben Hamida{\textendash}Reba\"{\i} and Paulo Pascutti and Paulo M. Bisch and David P. Perahia} } @article {2010|1788, title = {How does heparin prevent the p{H} inactivation of cathepsin {B}? Allosteric mechanism elucidated by docking and molecular dynamics.}, journal = {Bmc Genomics}, volume = {11, S5}, year = {2010}, author = {Mauricio G.S. Costa and Paulo R. Batista and Cl{\`a}udio S Shida and Charles H. Robert and Paulo M. Bisch and Pedro G. Pascutti} } @article {2010|1685, title = {Non adiabatic simulations of exciton dissociation in poly-p-phenylenevinylene oligomers}, journal = {J. Phys. Chem. A}, volume = {114}, year = {2010}, pages = {7661{\textendash}7670}, author = {M. Bedard-Hearn and Fabio Sterpone and P.J. Rossky} } @article {2010|1395, title = {{P}hotocontrol of protein activity in cultured cells and zebrafish with one- and two-photon illumination}, journal = {Chembiochem}, volume = {11}, year = {2010}, month = {mar}, pages = {653{\textendash}663}, author = {Sinha, D. K. and Neveu, P. and Gagey, N. and Aujard, I. and Benbrahim-Bouzidi, C. and Le Saux, T. and Rampon, C. and Gauron, C. and Goetz, B. and Dubruille, S. and Marc Baaden and Volovitch, M. and Bensimon, D. and Vriz, S. and Jullien, L.} } @conference {2010|1459, title = {A Rendering Method for Small Molecules up to Macromolecular Systems: HyperBalls Accelerated by Graphics Processors}, booktitle = {JOBIM}, year = {2010}, author = {Matthieu Chavent and A. Vanel and B. L{\'e}vy and B. Raffin and A. Tek and Marc Baaden} } @article {2010|1977, title = {Side-chain rotamer transitions at protein-protein interfaces}, journal = {Proteins: Struct., Funct., Bioinf.}, volume = {78}, year = {2010}, pages = {3219{\textendash}25}, author = {Mainak Guharoy and Jo\�el Janin and Charles H. Robert} } @article {2010, title = {The VLITL aggregation-prone motif might trigger amyloid fibril formation of fibrinogen A alpha-chain frameshift variants in vivo}, journal = {Amyloid-journal of Protein Folding Disorders}, volume = {17}, number = {Suppl. 1}, year = {2010}, note = {12th International Symposium on Amyloidosis from Molecular Mechanisms Toward the Cure of Systemic Amyloidoses, Rome, ITALY, APR 18-21, 2010}, pages = {96{\textendash}97}, author = {Valleix, S. and Philippe Derreumaux and Garnier, C. and Briki, F. and Boimard, M. and Doucet, J. and Rioux-Leclercq, N. and Martin, L. and Grateau, G. and Delpech, M. and Le Pogamp, P.} } @article {2010|1649, title = {Water reorientation, hydrogen-bond dynamics and 2D-IR spectroscopy next to an extended hydrophobic surface.}, journal = {Farad. Discuss.}, volume = {146}, year = {2010}, pages = {263{\textendash}281}, abstract = {

The dynamics of water next to hydrophobic groups is critical for several fundamental biochemical processes such as protein folding and amyloid fiber aggregation. Some biomolecular systems, like melittin or other membrane-associated proteins, exhibit extended hydrophobic surfaces. Due to the strain these surfaces impose on the hydrogen (H)-bond network, the water molecules shift from the clathrate-like arrangement observed around small solutes to an anticlathrate-like geometry with some dangling OH bonds pointing toward the surface. Here we examine the water reorientation dynamics next to a model hydrophobic surface through molecular dynamics simulations and analytic modeling. We show that the water OH bonds lying next to the hydrophobic surface fall into two subensembles with distinct dynamical reorientation properties. The first is the OH bonds tangent to the surface; these exhibit a behavior similar to the water OHs around small hydrophobic solutes, i.e. with a moderate reorientational slowdown explained by an excluded volume effect due to the surface. The second is the dangling OHs pointing toward the surface: these are not engaged in any H-bond, reorient much faster than in the bulk, and exhibit an unusual anisotropy decay which becomes negative for delays of a few picoseconds. The H-bond dynamics, i.e. the exchanges between the different configurations, and the resulting anisotropy decays are analyzed within the analytic extended jump model. We also show that a recent spectroscopy technique, two-dimensional time resolved vibrational spectroscopy (2D-IR), can be used to selectively follow the dynamics of dangling OHs, since these are spectrally distinct from H-bonded ones. By computing the first 2D-IR spectra of water next to a hydrophobic surface, we establish a connection between the spectral dynamics and the dynamical properties that we obtain directly from the simulations.

}, issn = {1359-6640}, author = {Guillaume Stirnemann and Rossky, Peter J and Hynes, James T and Laage, Damien} } @article {2009|1394, title = {Disulfide bond substitution by directed evolution in an engineered binding-protein scaffold.}, journal = {Chembiochem}, volume = {10}, year = {2009}, pages = {1349{\textendash}1359}, author = {Antoine Drevelle and Agathe Urvoas and M{\'e}riam Ben Hamida-Rebai and G{\'e}rard Van Vooren and Magali Nicaise and Marie Valerio-Lepiniec and Michel Desmadril and Charles H. Robert and Philippe Minard} } @article {2009|1486, title = {Free-Energy Landscape of RNA Hairpins Constructed via Dihedral Angle Principal Component Analysis}, journal = {J. Phys. Chem. B}, volume = {113}, number = {52}, year = {2009}, month = {dec}, pages = {16660{\textendash}16668}, author = {Riccardi, Laura and Phuong Hoang Nguyen and Stock, Gerhard} } @article {2009|1440, title = {Nonadiabatic mixed quantum-classical dynamic simulation of pi-stacked oligophenylenevinylenes}, journal = {J. Phys. Chem. A}, volume = {113}, number = {15}, year = {2009}, pages = {3427{\textendash}30}, author = {Sterpone, Fabio and Bedard-Hearn, Michael J and Rossky, Peter J} } @article {2009|1779, title = {Role of nucleic acid binding in Sir3p-dependent interactions with chromatin fibers.}, journal = {Biochemistry}, volume = {48}, number = {2}, year = {2009}, month = {jan}, pages = {276{\textendash}288}, publisher = {Department of Biological Sciences and Cell Differentiation and Development Center, Marshall University, Huntington, West Virginia 25755, USA.}, abstract = {

Recent studies of the mechanisms involved in the regulation of gene expression in eukaryotic organisms depict a highly complex process requiring a coordinated rearrangement of numerous molecules to mediate DNA accessibility. Silencing in Saccharomyces cerevisiae involves the Sir family of proteins. Sir3p, originally described as repressing key areas of the yeast genome through interactions with the tails of histones H3 and H4, appears to have additional roles in that process, including involvement with a DNA binding component. Our in vitro studies focused on the characterization of Sir3p-nucleic acid interactions and their biological functions in Sir3p-mediated silencing using binding assays, EM imaging, and theoretical modeling. Our results suggest that the initial Sir3p recruitment is partially DNA-driven, highly cooperative, and dependent on nucleosomal features other than histone tails. The initial step appears to be rapidly followed by the spreading of silencing using linker DNA as a track.

}, doi = {10.1021/bi801705g}, author = {Nicholas L Adkins and Steve J McBryant and Cotteka N Johnson and Jennifer M Leidy and Christopher L Woodcock and Charles H Robert and Jeffrey C Hansen and Philippe T Georgel} } @article {2008|1940, title = {HU binds and folds single-stranded DNA}, journal = {Nucl. Acids Res.}, volume = {36}, number = {3}, year = {2008}, pages = {1026{\textendash}1036}, author = {Dmitri Kamashev and Anna Balandina and Alexey K Mazur and Paola B. Arimondo and Josette Rouviere-Yaniv} } @article {2008|1829, title = {Molecular modeling and simulation of conjugated polymer oligomers: ground and excited state chain dynamics of PPV in the gas phase}, journal = {J. Phys. Chem. B}, volume = {112}, number = {16}, year = {2008}, pages = {4983{\textendash}93}, author = {Sterpone, Fabio and Rossky, Peter J} } @article {2007|1776, title = {The conserved glycine/alanine residue of the active-site loop containing the putative acetylCoA-binding motif is essential for the overall structural integrity of Mesorhizobium loti arylamine N-acetyltransferase 1}, journal = {Biochem. Biophys. Res. Commun.}, volume = {361}, number = {1}, year = {2007}, month = {sep}, pages = {256{\textendash}262}, doi = {10.1016/j.bbrc.2007.07.034}, author = {Atmane, Noureddine and Dairou, Julien and Flatters, Delphine and Martins, Marta and Pluvinage, Benjamin and Philippe Derreumaux and Dupret, Jean-Marie and Rodrigues-Lima, Fernando} } @article {2007|1828, title = {How protein surfaces induce anomalous dynamics of hydration water}, journal = {J. Phys. Chem. B}, volume = {111}, number = {26}, year = {2007}, pages = {7584{\textendash}90}, abstract = {Water around biomolecules slows down with respect to pure water, and both rotation and translation exhibit anomalous time dependence in the hydration shell. The origin of such behavior remains elusive. We use molecular dynamics simulations of water dynamics around several designed protein models to establish the connection between the appearance of the anomalous dynamics and water-protein interactions. For the first time we quantify the separate effect of protein topological and energetic disorder on the hydration water dynamics. When a static protein structure is simulated, we show that both types of disorder contribute to slow down water diffusion, and that allowing for protein motion, increasing the spatial dimensionality of the interface, reduces the anomalous character of hydration water. The rotation of water is, instead, altered by the energetic disorder only; indeed, when electrostatic interactions between the protein and water are switched off, water reorients even faster than in the bulk. The dynamics of water is also related to the collective structure{\textendash}{\`a} voir the hydrogen bond (H-bond) network{\textendash}formed by the solvent enclosing the protein surface. We show that, as expected for a full hydrated protein, when the protein surface offers pinning sites (charged or polar sites), the superficial water-water H-bond network percolates throughout the whole surface, hindering the water diffusion, whereas it does not when the protein surface lacks electrostatic interactions with water and the water diffusion is enhanced.}, author = {Pizzitutti, Francesco and Marchi, Massimo and Sterpone, Fabio and Rossky, Peter J} } @article {2006|1943, title = {Hfq variant with altered RNA binding functions}, journal = {Nucleic Acids Res.}, volume = {34}, number = {2}, year = {2006}, pages = {709{\textendash}720}, doi = {10.1093/nar/gkj464}, author = {Ziolkowska, K and Philippe Derreumaux and Folichon, M and Pellegrini, O and Regnier, P and Boni, IV and Hajnsdorf, E} } @article {2006|1810, title = {Normal mode analysis as a prerequisite for drug design: Application to matrix metalloproteinases inhibitors}, journal = {Febs Lett.}, volume = {580}, number = {22}, year = {2006}, month = {oct}, pages = {5130{\textendash}5136}, abstract = {We demonstrate the utility of normal mode analysis in correctly predicting the binding modes of inhibitors in the active sites of matrix metalloproteinases (MMPs). We show the accuracy in predicting the positions of MMP-3 inhibitors is strongly dependent on which structure is used as the target, especially when it has been energy minimized. This dependency can be overcome by using intermediate structures generated along one of the normal modes previously calculated for a given target. These results may be of prime importance for further in silico drug discovery.}, doi = {10.1016/j.febslet.2006.08.037}, author = {Nicolas Floquet and Jean-Didier Mar{\'e}chal and Marie-Ange Badet-Denisot and Charles H Robert and Manuel Dauchez and David Perahia} } @article {2006|1658, title = {Odorant Binding and Conformational Dynamics in the Odorant-binding Protein}, journal = {J. Biol. Chem.}, volume = {281}, number = {40}, year = {2006}, month = {oct}, pages = {29929{\textendash}29937}, abstract = {In mammals, the olfactory epithelium secretes odorant-binding proteins (OBPs), which are lipocalins found freely dissolved in the mucus layer protecting the olfactory neurons. OBPs may act as passive transporters of predominantly hydrophobic odorant molecules across the aqueous mucus layer, or they may play a more active role in which the olfactory neuronal receptor recognizes the OBP-ligand complex. To better understand the molecular events accompanying the initial steps in the olfaction process, we have performed molecular dynamics studies of rat and pig OBPs with the odorant molecule thymol. These calculations provide an atomic level description of conformational changes and pathway intermediates that remain difficult to study directly. A series of eight independent molecular dynamics trajectories of rat OBP permitted the observation of a consensus pathway for ligand unbinding and the calculation of the potential of mean force (PMF) along this path. Titration microcalorimetry confirmed the specific binding of thymol to this protein with a strong hydrophobic component. In both rat and pig OBPs we observed lipocalin strand pair opening in the presence of ligand, consistent with potential roles of these proteins in olfactive receptor recognition.}, doi = {10.1074/jbc.M604869200}, author = {Eric Hajjar and David Perahia and Helene D{\'e}bat and Claude Nespoulous and Charles H. Robert} } @article {2006|1842, title = {Structural changes of region 1-16 of the Alzheimer disease amyloid beta-peptide upon zinc binding and in vitro aging}, journal = {J. Biol. Chem.}, volume = {281}, number = {4}, year = {2006}, pages = {2151{\textendash}2161}, author = {Severine Zirah and Sergey A. Kozin and Alexey K Mazur and Alain Blond and Michel Cheminant and Isabelle Segalas-Milazzo and Pascale Debey and Sylvie Rebuffat} } @article {2004|1867, title = {The antitumor properties of the alpha 3(IV)-(185-203) peptide from the NC1 domain of type IV collagen (tumstatin) are conformation-dependent}, journal = {J. Biol. Chem.}, volume = {279}, number = {3}, year = {2004}, month = {jan}, pages = {2091{\textendash}2100}, doi = {10.1074/jbc.M307736200}, author = {Floquet, N and Pasco, S and Ramont, L and Philippe Derreumaux and Laronze, JY and Nuzillard, JM and Maquart, FX and Alix, AJP and Monboisse, JC} } @article {2004|1807, title = {The C-terminal domain of Escherichia coli Hfq increases the stability of the hexamer}, journal = {Eur. J. Biochem.}, volume = {271}, number = {7}, year = {2004}, month = {apr}, pages = {1258{\textendash}1265}, doi = {10.1111/j.1432-1033.2004.04026.x}, author = {Arluison, V and Folichon, M and Marco, S and Philippe Derreumaux and Pellegrini, O and Seguin, J and Hajnsdorf, E and Regnier, P} } @article {2004|1824, title = {Integrating three views of Arf1 activation dynamics}, journal = {J. Mol. Biol.}, volume = {337}, number = {4}, year = {2004}, month = {apr}, pages = {969{\textendash}983}, author = {Robert, Charles H and Cherfils, Jacqueline and Mouawad, Liliane and Perahia, David} } @article {2004|1801, title = {Molecular cloning of a mollusk glucanase}, journal = {Comp. Biochem. Physiol.}, volume = {137}, number = {2}, year = {2004}, pages = {169{\textendash}178}, author = {Valeri B. Kozhemyako and Denis V. Rebrikov and Sergey A. Lukyanov and Ekaterina A. Bogdanova and Antoine Marin and Alexey K Mazur and Svetlana N. Kovalchuk and Elena V. Agafonova and Victoria V. Sova and Ludmila A. Elyakova and Valeri A. Rasskazov} } @article {2002, title = {Analysis of Protein Sequence/Structure Similarity Relationships}, journal = {Biophys. J.}, volume = {83}, year = {2002}, pages = {2781{\textendash}2791}, author = {H. H. Gan and R. A. Perow and S. Roy and J. Ko, M. Wu, J. Huang and S. Yan and A. Nicoletta and J. Vafai, D. Sun and L. Wang and J. E. Noah and S. Pasquali and T. Schlick} } @article {2002|1790, title = {Differential core histone binding behavior: {R}{N}{A} polymerase {I} promoter region vs 5{S} r{D}{N}{A} positioning {D}{N}{A} sequences}, journal = {Cell Biochem. Biophys.}, volume = {37}, number = {1}, year = {2002}, pages = {1{\textendash}13}, author = {Georgel, Philippe T and Robert, Charles H} } @article {2002|1599, title = {New insights into the allosteric mechanism of human hemoglobin from molecular dynamics simulations}, journal = {Biophys. J.}, volume = {82}, number = {6}, year = {2002}, month = {jun}, pages = {3224{\textendash}3245}, author = {Mouawad, Liliane and Perahia, David and Charles H. Robert and Guilbert, Christophe} } @article {2002|1902, title = {Structural modelling of the Sm-like protein Hfq from Escherichia coli}, journal = {J. Mol. Biol.}, volume = {320}, number = {4}, year = {2002}, month = {jul}, pages = {705{\textendash}712}, doi = {10.1016/S0022-2836(02)00548-X}, author = {Arluison, V and Philippe Derreumaux and Allemand, F and Folichon, M and Hajnsdorf, E and Regnier, P} } @inbook {2001|1640, title = {Internal coordinate simulation method}, booktitle = {Computational Biochemistry and Biophysics}, year = {2001}, pages = {115{\textendash}131}, publisher = {Marcel Dekker}, organization = {Marcel Dekker}, address = {New York}, author = {Alexey K Mazur}, editor = {Oren M. Becker and Alexander D. MacKerell and Benoit Roux and Masakatsu Watanabe} } @article {2001|1841, title = {Sheep prion protein synthetic peptide spanning helix 1 and beta-strand 2 (residues 142-166) shows beta-hairpin structure in solution}, journal = {J. Biol. Chem.}, volume = {276}, number = {49}, year = {2001}, pages = {46364{\textendash}46370}, author = {S. A. Kozin and G. Bertho and Alexey K Mazur and H. Rabesona and J. P. Girault and T. Haertle and M. Takahashi and P. Debey and G. H. Hoa} } @article {1998|1530, title = {Folding and Aggregation of Designed Protein Chains}, journal = {Proc. Natl. Acad. Sci. Usa}, volume = {95}, year = {1998}, pages = {12930{\textendash}1293}, author = {R.A. Broglia and G. Tiana and S. Pasquali and H. E. Roman and E. Vigezzi} } @article {1998|1822, title = {A soft, mean{\textendash}field potential derived from crystal contacts for predicting protein{\textendash}protein interactions}, journal = {J. Mol. Biol.}, volume = {283}, number = {5}, year = {1998}, month = {nov}, pages = {1037{\textendash}1047}, author = {Robert, C H and Janin, J} } @article {1997|1680, title = {Collective-variable Monte Carlo simulation of DNA}, journal = {J. Comp. Chem.}, volume = {18}, year = {1997}, pages = {2001{\textendash}2011}, author = {H. Gabb and Chantal Pr{\'e}vost and G. Bertucat and Charles H. Robert and Richard Lavery} } @article {1996|1666, title = {Finding and visualizing nucleic acid base stacking}, journal = {J Mol Graph}, volume = {14}, number = {1}, year = {1996}, month = {feb}, pages = {6{\textendash}11}, author = {Gabb, H A and Sanghani, S R and Charles H. Robert and Chantal Pr{\'e}vost} } @article {1995|1601, title = {Estimating friction coefficients of mixed globular/chain molecules, such as protein/{DNA} complexes}, journal = {Biophys. J.}, volume = {69}, number = {3}, year = {1995}, month = {sep}, pages = {840{\textendash}848}, author = {Charles H. Robert} } @article {1995|1969, title = {Significance of bound water to local chain conformations in protein crystals}, journal = {Proc. Natl. Acad. Sci. U.s.a.}, volume = {92}, number = {16}, year = {1995}, month = {aug}, pages = {7600{\textendash}7604}, author = {Robert, C H and Ho, P S} } @article {1994|1968, title = {Three-dimensional structure of extended chromatin fibers as revealed by tapping-mode scanning force microscopy}, journal = {Proc. Natl. Acad. Sci. U.s.a.}, volume = {91}, number = {24}, year = {1994}, month = {nov}, pages = {11621{\textendash}11625}, abstract = {Unfixed chicken erythrocyte chromatin fibers in very low salt have been imaged with a scanning force microscope operating in the tapping mode in air at ambient humidity. These images reveal a three-dimensional organization of the fibers. The planar "zig-zag" conformation is rare, and extended "beads-on-a-string" fibers are seen only in chromatin depleted of histones H1 and H5. Glutaraldehyde fixation reveals very similar structures. Fibers fixed in 10 mM salt appear somewhat more compacted. These results, when compared with modeling studies, suggest that chromatin fibers may exist as irregular three-dimensional arrays of nucleosomes even at low ionic strength.}, keywords = {Animals, Atomic Force, Biological, Chickens, Chromatin, Fixatives, Histones, Microscopy, Models, Non-P.H.S., Non-U.S. Gov{\textquoteright}t, Osmolar Concentration, P.H.S., Research Support, Sodium Chloride, U.S. Gov{\textquoteright}t}, author = {S. H. Leuba and G. Yang and C. Robert and B. Samori and K. van Holde and J. Zlatanova and C. Bustamante} } @article {1993|1628, title = {Persistence analysis of the static and dynamical helix deformations of DNA oligonucleotides: application to the crystal structure and molecular dynamics simulation of d(CGCGAATTCGCG)2}, journal = {Biopolymers}, volume = {33}, year = {1993}, month = {mar}, pages = {335{\textendash}50}, abstract = {

A theory and graphical presentation for the analysis of helix structure and deformations in oligonucleotides is presented. The parameters \"persistence\" and \"flexibility\" as defined in the configurational statistics of polymers of infinite length are reformulated at the oligonucleotide level in an extension of J. A. Schellman\&$\#$39;s method [(1974) Biopolymers, Vol. 17, pp. 217-226], and used as a basis for a systematic \"Persistence Analysis\" of the helix deformation properties for all possible subsequences in the structure. The basis for the analysis is a set of link vectors referenced to individual base pairs, and is limited to sequences exhibiting only perturbed rod-like behavior, i.e., below the threshold for supercoiling. The present application of the method is concerned with a physical model for the angular component of bending, so the link vectors are defined as the unit components of a global helix axis obtained by the procedure \"Curves\" of R. Lavery and H. Sklenar [(1988) J. Biomol. Struct. Dynam., Vol. 6, pp. 63-91; (1989) ibid., Vol. 6, pp. 655-667]. A discussion of the relationship between global bending and relative orientation of base pairs is provided. Our approach is illustrated by analysis of some model oligonucleotide structures with intrinsic kinks, the crystal structure of the dodecamer d(CGCGAATTCGCG)2, and the results of two molecular dynamics simulations on this dodecamer using two variations of the GROMOS force field. The results indicate that essentially all aspects of curvature in short oligonucleotides can be determined, such as the position and orientation of each bend, the sharpness or smoothness, and the location and linearity of subsequences. In the case of molecular dynamics simulations, where a Boltzmann ensemble of structures is analyzed, the spatial extent of the deformations (flexibility) is also considered.

}, doi = {10.1002/bip.360330303}, author = {Chantal Pr{\'e}vost and Louise-May, S and Ravishanker, G and Richard Lavery and Beveridge, D L} } @article {1992|1596, title = {Kinetics of pore-mediated release of marker molecules from liposomes or cells}, journal = {Biophys. Chem.}, volume = {42}, number = {3}, year = {1992}, month = {apr}, pages = {291{\textendash}296}, author = {Schwarz, G and Charles H. Robert} } @article {1991|1593, title = {A combined study of aggregation, membrane affinity and pore activity of natural and modified melittin}, journal = {Biochim. Biophys. Acta}, volume = {1069}, number = {1}, year = {1991}, month = {oct}, pages = {77{\textendash}86}, author = {Stankowski, S and Pawlak, M and Kaisheva, E and Charles H. Robert and Schwarz, G} } @conference {1991|1580, title = {Methodological considerations on molecular dynamics simulations of DNA oligonucleotides}, booktitle = {AIP Conference Proceedings}, year = {1991}, month = {oct}, publisher = {AIP}, organization = {AIP}, abstract = {

Methodological aspects of solvent effects, simulation protocol, analysis and visualization of results, accuracy, and sensitivity of results to force field parametrization are discussed for molecular dynamics simulation on oligonucleotides. Recent results comparing AMBER, CHARMM and GROMOS force fields are included. The calculation of build\‚{\"A}{\^e}up curves for the nuclear Overhauser effect from simulations is also described.

}, doi = {10.1063/1.41314}, author = {Beveridge, DL and Swaminathan, S and Ravishanker, G and Withka, J and Srinivasan, J and Chantal Pr{\'e}vost and Louise-May, S and DiCapua, FM and Bolton, PH} } @article {1991|1719, title = {NMR and conformational studies of the cyclobutane ring involved in the bicyclo [4.2. 0] octane system of a tetracyclic diterpene structure}, journal = {Magn. Reson. Chem.}, volume = {29}, year = {1991}, pages = {870{\textendash}877}, abstract = {

Conformational studies were performed on the bicyclo [4.2.0] octane system of a series of related tetracyclic diterpenes, using molecular mechanics and 1H NMR. Both methods gave compatible results, but did not permit the deduction of any quantitative relationship linking the vicinal coupling constants to the cyclobutane dihedral angles. Nevertheless, the Karplus relationship allowed a qualitative interpretation of the coupling constants in terms of conformation. A set of characteristic 1H NMR coupling constants was obtained which allows the interpretation of the 1H NMR spectrum of any compound presenting a similar system.

}, doi = {DOI: 10.1002/mrc.1260290903}, url = {http://onlinelibrary.wiley.com/doi/10.1002/mrc.1260290903/full}, author = {Do Khac Manh, Duc and Fetizon, Marcel and Chantal Pr{\'e}vost and Roy, Pierre} } @article {1990|1786, title = {A hierarchical {\textquoteleft}nesting{\textquoteright} approach to describe the stability of alpha helices with side-chain interactions}, journal = {Biopolymers}, volume = {30}, number = {3-4}, year = {1990}, pages = {335{\textendash}347}, author = {Robert, C H} } @article {1990, title = {Pore formation kinetics in membranes, determined from the release of marker molecules out of liposomes or cells}, journal = {Biophys. J.}, volume = {58}, year = {1990}, pages = {577{\textendash}583}, author = {Schwarz, Gerhard and Charles H. Robert} } @article {1989|1785, title = {Allosteric formulation of thermal transitions in macromolecules, including effects of ligand binding and oligomerization}, journal = {Biopolymers}, volume = {28}, number = {10}, year = {1989}, month = {oct}, pages = {1705{\textendash}1729}, author = {Robert, C H and Colosimo, A and Gill, S J} } @article {1989|1821, title = {Binding of oxygen and carbon monoxide to the hemocyanin from the spiny lobster}, journal = {J. Mol. Biol.}, volume = {207}, number = {4}, year = {1989}, month = {jun}, pages = {829{\textendash}832}, author = {Connelly, P R and Johnson, C R and Robert, C H and Bak, H J and Gill, S J} } @article {1988|1597, title = {Analysis and parameter resolution in highly cooperative systems}, journal = {Biophys. Chem.}, volume = {30}, number = {2}, year = {1988}, month = {jun}, pages = {133{\textendash}141}, author = {Gill, S J and Connelly, P R and Di Cera, E and Charles H. Robert} } @inbook {1988, title = {Analysis of allosteric systems}, booktitle = {Biochemical Thermodynamics}, year = {1988}, publisher = {Elsevier}, organization = {Elsevier}, edition = {2nd}, address = {Holland}, author = {Gill, S. J. and Robert, C. H. and Wyman, J.} } @article {1988|1858, title = {Enthalpy of dimerization of benzene in water}, journal = {J. Phys. Chem.}, volume = {92}, year = {1988}, pages = {3623{\textendash}3625}, author = {D. Hallen and I. Wadso and D. J. Wasserman and C. H. Robert and S. J. Gill} } @article {1988|1589, title = {Linkage of organic phosphates to oxygen binding in human hemoglobin at high concentrations}, journal = {Biochemistry}, volume = {27}, number = {18}, year = {1988}, month = {sep}, pages = {6835{\textendash}6843}, author = {Charles H. Robert and Fall, L and Gill, S J} } @article {1988|1590, title = {Nested allosteric interaction in tarantula hemocyanin revealed through the binding of oxygen and carbon monoxide}, journal = {Biochemistry}, volume = {27}, number = {18}, year = {1988}, month = {sep}, pages = {6901{\textendash}6908}, author = {Decker, H and Connelly, P R and Charles H. Robert and Gill, S J} } @article {1988|1591, title = {Quantitative analysis of linkage in macromolecules when one ligand is present in limited total quantity}, journal = {Biochemistry}, volume = {27}, number = {18}, year = {1988}, month = {sep}, pages = {6829{\textendash}6835}, author = {Charles H. Robert and Gill, S J and Wyman, J} } @article {1987|1777, title = {Allosteric interpretation of the oxygen-binding reaction of human hemoglobin tetramers}, journal = {Biochemistry}, volume = {26}, number = {13}, year = {1987}, month = {jun}, pages = {4003{\textendash}4008}, author = {Di Cera, E and Robert, C H and Gill, S J} } @inbook {1987, title = {Calorimetric analysis of oxygen binding to lobster hemocyanin}, booktitle = {Invertebrate Oxygen Carriers}, year = {1987}, publisher = {Springer-Verlag}, organization = {Springer-Verlag}, address = {Berlin}, author = {Parody-Morreale, A. and Robert, C. H. and Gill, S. J.} } @article {1987|1818, title = {Calorimetric studies of oxygen and carbon monoxide binding to human hemoglobin. Sequential binding heats for oxygen}, journal = {J. Biol. Chem.}, volume = {262}, number = {23}, year = {1987}, month = {aug}, pages = {10994{\textendash}10999}, author = {Parody-Morreale, A and Robert, C H and Bishop, G A and Gill, S J} } @article {1987|1820, title = {Carbon dioxide and oxygen linkage in human hemoglobin tetramers}, journal = {J. Mol. Biol.}, volume = {196}, number = {4}, year = {1987}, month = {aug}, pages = {927{\textendash}934}, author = {Doyle, M L and Di Cera, E and Robert, C H and Gill, S J} } @article {1987|1991, title = {Gas-solution microcalorimeter for determining heat binding curves}, journal = {Rev. Sci. Instr.}, volume = {58}, year = {1987}, pages = {632{\textendash}638}, author = {Bishop, G. A. and Parody-Morreale, A. and Robert, C. and and Gill, S. J.} } @inbook {1987|1429, title = {Nesting- An extension of the MWC model and its application to tarantula hemocyanin}, booktitle = {Invertebrate Oxygen Carriers}, year = {1987}, publisher = {Springer-Verlag}, organization = {Springer-Verlag}, address = {Berlin}, author = {Decker, H. and Robert, C. H. and Gill, S. J.} } @article {1987|1967, title = {Nesting: hierarchies of allosteric interactions}, journal = {Proc. Natl. Acad. Sci. U.s.a.}, volume = {84}, number = {7}, year = {1987}, month = {apr}, pages = {1891{\textendash}1895}, author = {Robert, C H and Decker, H and Richey, B and Gill, S J and Wyman, J} } @article {1987|1592, title = {Oxygen binding constants for human hemoglobin tetramers}, journal = {Biochemistry}, volume = {26}, number = {13}, year = {1987}, month = {jun}, pages = {3995{\textendash}4002}, author = {Gill, S J and Di Cera, E and Doyle, M L and Bishop, G A and Charles H. Robert} } @article {1986|1781, title = {Analysis of zeros of binding polynomials for tetrameric hemoglobins}, journal = {Biophys. Chem.}, volume = {24}, number = {3}, year = {1986}, month = {aug}, pages = {295{\textendash}309}, author = {Connelly, P R and Charles H. Robert and Briggs, W E and Gill, S J} } @article {1986|1602, title = {Cooperative free energies for nested allosteric models as applied to human hemoglobin}, journal = {Biophys. J.}, volume = {50}, number = {4}, year = {1986}, month = {oct}, pages = {747{\textendash}752}, author = {Gill, S J and Charles H. Robert and Coletta, M and Di Cera, E and Brunori, M} } @article {1985|1855, title = {Dry deposition of nitric acid to grass}, journal = {J. Geophys. Res.}, volume = {90}, year = {1985}, pages = {2085{\textendash}2090}, author = {B. A. Huebert and C. H. Robert} }