@article {2024, title = {A Perspective on the Prospective Use of AI in Protein Structure Prediction}, journal = {J Chem Inf Model}, volume = {64}, year = {2024}, month = {Jan}, pages = {26{\textendash}41}, author = {Versini, R. and Sritharan, S. and Aykac Fas, B. and Tubiana, T. and Aimeur, S. Z. and Henri, J. and Erard, M. and N{\"u}sse, O. and Andreani, J. and Baaden, M. and Fuchs, P. and Galochkina, T. and Chatzigoulas, A. and Cournia, Z. and Santuz, H. and S Sacquin-Mora and Taly, A.} } @article {2022|2151, title = {Symmetry-Adapted Restraints for Binding Free Energy Calculations.}, journal = {J Chem Theory Comput}, year = {2022}, month = {2022 Mar 01}, abstract = {

Binding free energy calculations rely critically on a precise definition of the bound state and well-designed ligand restraints to ensure that binding free energy calculations converge rapidly and yield estimates of well-defined thermodynamic quantities. The distance-to-bound-configuration (DBC) is a single variable that can precisely delineate the bound state of a ligand including translational, rotational and conformational degrees of freedom and has been successfully used to capture binding modes with complex geometries. DBC is defined as the root-mean-square deviation (RMSD) of ligand coordinates in the frame of reference of the binding site. In the special case where the ligand features symmetry-equivalent atoms, a standard RMSD arbitrarily distinguishes equivalent poses, mixing equivalent and nonequivalent degrees of freedom, and preventing the precise delineation of the bound state ensemble, which negates the benefits of defining a flat-bottom binding restraint. To remedy this, we introduce a symmetry-adapted DBC coordinate where the RMSD is minimized over permutations of equivalent ligand atoms. This coordinate is implemented in a portable software library, the Collective Variables Module. We tested the approach by computing the absolute binding free energy of benzene to the engineered site of a mutant lysozyme (L99A/M102H) using alchemical free energy perturbation. We found that the symmetry-adapted restraint leads to well-behaved convergence of both the decoupling free energy in the binding site and the restrained free energy in the gas phase, recovering the affinity computed using a classic center-of-mass restraint. Thus, symmetry-adapted DBC seamlessly generalizes the benefits of DBC restraints to the case of symmetric ligands. The underlying symmetric RMSD coordinate can also be used for analyzing or biasing simulations in other contexts than affinity predictions.

}, issn = {1549-9626}, doi = {10.1021/acs.jctc.1c01235}, author = {Ebrahimi, Mina and J{\'e}r{\^o}me H{\'e}nin} } @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|2067, title = {An inter-dimer allosteric switch controls NMDA receptor activity}, journal = {The EMBO journal}, volume = {38}, year = {2019}, author = {Esmenjaud, Jean-Baptiste and Stroebel, David and Chan, Kelvin and Grand, Teddy and David, M{\'e}lissa and Wollmuth, Lonnie P and Antoine Taly and Paoletti, Pierre} } @article {2019|2119, title = {Stability Effect of Quinary Interactions Reversed by Single Point Mutations}, journal = {Journal of the American Chemical Society}, volume = {141}, year = {2019}, pages = {4660-4669}, doi = {10.1021/jacs.8b13025}, url = {https://doi.org/10.1021/jacs.8b13025}, author = {Gnutt, David and Timr, Stepan and Ahlers, Jonas and K{\"o}nig, Benedikt and Manderfeld, Emily and Heyden, Matthias and Sterpone, Fabio and Ebbinghaus, Simon} } @article {2018|2086, title = {Analyzing protein topology based on Laguerre tessellation of a pore-traversing water network.}, journal = {Sci Rep}, volume = {8}, year = {2018}, month = {2018 09 10}, pages = {13540}, abstract = {

Given the tight relation between protein structure and function, we present a set of methods to analyze protein topology, implemented in the VLDP program, relying on Laguerre space partitions built from series of molecular dynamics snapshots. The Laguerre partition specifies inter-atomic contacts, formalized in graphs. The deduced properties are the existence and count of water aggregates, possible passage ways and constrictions, the structure, connectivity, stability and depth of the water network. As a test-case, the membrane protein FepA is investigated in its full environment, yielding a more precise description of the protein surface. Inside FepA, the solvent splits into isolated clusters and an intricate network connecting both sides of the lipid bilayer. The network is dynamic, connections set on and off, occasionally substantially relocating traversing paths. Subtle differences are detected between two forms of FepA, ligand-free and complexed with its natural iron carrier, the enterobactin. The complexed form has more constricted and more centered openings in the upper part whereas, in the lower part, constriction is released: two main channels between the plug and barrel lead directly to the periplasm. Reliability, precision and the variety of topological features are the main interest of the method.

}, keywords = {Bacterial Outer Membrane Proteins, Carrier Proteins, Enterobactin, Molecular Dynamics Simulation, Protein Stability, Protein Structure, Secondary, Receptors, Cell Surface, Structure-Activity Relationship, Water}, issn = {2045-2322}, doi = {10.1038/s41598-018-31422-5}, author = {Esque, J{\'e}r{\'e}my and Sansom, Mark S P and Marc Baaden and Oguey, Christophe} } @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 {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} } @article {2016|1672, title = {A Novel Bifunctional Alkylphenol Anesthetic Allows Characterization of gamma-Aminobutyric Acid, Type A (GABAA), Receptor Subunit Binding Selectivity in Synaptosomes.}, journal = {J. Biol. Chem}, volume = {291}, year = {2016}, month = {sep}, pages = {20473{\textendash}86}, abstract = {

Propofol, an intravenous anesthetic, is a positive modulator of the GABAA receptor, but the mechanistic details, including the relevant binding sites and alternative targets, remain disputed. Here we undertook an in-depth study of alkylphenol-based anesthetic binding to synaptic membranes. We designed, synthesized, and characterized a chemically active alkylphenol anesthetic (2-((prop-2-yn-1-yloxy)methyl)-5-(3-(trifluoromethyl)-3H-diazirin-3-yl)phenol, AziPm-click (1)), for affinity-based protein profiling (ABPP) of propofol-binding proteins in their native state within mouse synaptosomes. The ABPP strategy captured approximately 4\% of the synaptosomal proteome, including the unbiased capture of five alpha or beta GABAA receptor subunits. Lack of gamma2 subunit capture was not due to low abundance. Consistent with this, independent molecular dynamics simulations with alchemical free energy perturbation calculations predicted selective propofol binding to interfacial sites, with higher affinities for alpha/beta than gamma-containing interfaces. The simulations indicated hydrogen bonding is a key component leading to propofol-selective binding within GABAA receptor subunit interfaces, with stable hydrogen bonds observed between propofol and alpha/beta cavity residues but not gamma cavity residues. We confirmed this by introducing a hydrogen bond-null propofol analogue as a protecting ligand for targeted-ABPP and observed a lack of GABAA receptor subunit protection. This investigation demonstrates striking interfacial GABAA receptor subunit selectivity in the native milieu, suggesting that asymmetric occupancy of heteropentameric ion channels by alkylphenol-based anesthetics is sufficient to induce modulation of activity.

}, keywords = {anesthesia, anesthetic, click chemistry, GABA receptor, photoaffinity labeling}, doi = {10.1074/jbc.M116.736975}, author = {Woll, Kellie A. and Murlidaran, Sruthi and Pinch, Benika J. and J{\'e}r{\^o}me H{\'e}nin and Wang, Xiaoshi and Salari, Reza and Covarrubias, Manuel and Dailey, William P. and Grace Brannigan and Garcia, Benjamin A. and Roderic G Eckenhoff} } @article {2015|1582, title = {The elastic free energy of a tandem modular protein under force.}, journal = {Biochem. Biophys. Res. Comm.}, year = {2015}, pages = {1{\textendash}5}, keywords = {free energy landscape, tandem modular protein}, issn = {0006291X}, doi = {10.1016/j.bbrc.2015.03.051}, url = {http://linkinghub.elsevier.com/retrieve/pii/S0006291X15004866}, author = {Valle-Orero, Jessica and Eckels, Edward and Guillaume Stirnemann and Popa, Ionel and Berkovich, Ronen and Fernandez, Julio M.} } @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 {2013|1528, title = {{G}ame on, science - how video game technology may help biologists tackle visualization challenges}, journal = {Plos One}, volume = {8}, number = {3}, year = {2013}, pages = {e57990}, author = {Lv, Z. and Tek, A. and Da Silva, F. and Empereur-mot, C. and Matthieu Chavent and Marc Baaden} } @article {2012|1960, title = {General Anesthetics Predicted to Block the {GLIC} Pore with Micromolar Affinity}, journal = {Plos Comput. Biol.}, volume = {8}, number = {5}, year = {2012}, pages = {e1002532}, publisher = {Public Library of Science}, abstract = {

Author Summary

Although general anesthesia is performed every day on thousands of people, its detailed microscopic mechanisms are not known. What is known is that general anesthetic drugs modulate the activity of ion channels in the central nervous system. These channels are proteins that open in response to binding of neurotransmitter molecules, creating an electric current through the cell membrane and thus propagating nerve impulses between cells. One possible mechanism for ion channel inhibition by anesthetics is that the drugs bind inside the pore of the channels, blocking ion current. Here we investigate such a pore block mechanism by computing the strength of the drugs{\textquoteright} interaction with the pore {\textendash} and hence the likelihood of binding, in the case of GLIC, a bacterial channel protein. The results, obtained from numerical simulations of atomic models of GLIC, indicate that the anesthetics isoflurane and propofol have a tendency to bind in the pore that is strong enough to explain blocking of the channel, even at low concentration of the drugs.

}, doi = {10.1371/journal.pcbi.1002532}, url = {http://dx.doi.org/10.1371\%2Fjournal.pcbi.1002532}, author = {LeBard, David N. and J{\'e}r{\^o}me H{\'e}nin and Roderic G Eckenhoff and Michael L Klein and Brannigan, Grace} } @article {2012|1527, title = {{S}tructure-function analysis of the {NFL}-{TBS}.40-63 peptide corresponding to the binding site of tubulin on the light neurofilament subunit}, journal = {Plos One}, volume = {7}, year = {2012}, pages = {e49436}, author = {Berges, R. and Balzeau, J. and Takahashi, M. and Chantal Pr{\'e}vost and Eyer, J.} } @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} } @article {2011|1393, title = {GPU-powered tools boost molecular visualization}, journal = {Briefings Bioinf.}, volume = {12}, year = {2011}, month = {feb}, pages = {689{\textendash}701}, author = {Matthieu Chavent and B. L{\'e}vy and M. Krone and K. Bidmon and J. P. Nomin{\'e} and T. Ertl and Marc Baaden} } @article {2010|1865, title = {An atomistic model for simulations of the general anesthetic isoflurane}, journal = {J. Phys. Chem. B}, volume = {114}, number = {1}, year = {2010}, pages = {604{\textendash}612}, publisher = {Laboratoire d{\textquoteright}Ing{\'e}nierie des Syst{\`e}mes Macromol{\'e}culaires, CNRS, Marseille, France. jhenin@ifr88.cnrs-mrs.fr}, abstract = {An atomistic model of isoflurane is constructed and calibrated to describe its conformational preferences and intermolecular interactions. The model, which is compatible with the CHARMM force field for biomolecules, is based on target quantities including bulk liquid properties, molecular conformations, and local interactions with isolated water molecules. Reference data is obtained from tabulated thermodynamic properties and high-resolution structural information from gas-phase electron diffraction, as well as DFT calculations at the B3LYP level. The model is tested against experimentally known solvation properties in water and oil, and shows quantitative agreement. In particular, isoflurane is faithfully described as lipophilic, yet nonhydrophobic, a combination of properties critical to its pharmacological activity. Intermolecular interactions of the model are further probed through simulations of the binding of isoflurane to a binding site in horse spleen apoferritin (HSAF). The observed binding mode compares well with crystallographic data, and the calculated binding affinities are compatible with experimental results, although both computational and experimental measurements are challenging and provide results with limited precision. The model is expected to be useful for detailed simulations of the elementary molecular processes associated with anesthesia. Full parameters are provided as Supporting Information.}, doi = {10.1021/jp9088035}, author = {J{\'e}r{\^o}me H{\'e}nin and Grace Brannigan and William P Dailey and Roderic G Eckenhoff and Michael L Klein} } @article {2010|1971, title = {Multiple binding sites for the general anesthetic isoflurane identified in the nicotinic acetylcholine receptor transmembrane domain.}, journal = {Proc. Natl. Acad. Sci. U.s.a.}, volume = {107}, number = {32}, year = {2010}, pages = {14122{\textendash}14127}, abstract = {An extensive search for isoflurane binding sites in the nicotinic acetylcholine receptor (nAChR) and the proton gated ion channel from Gloebacter violaceus (GLIC) has been carried out based on molecular dynamics (MD) simulations in fully hydrated lipid membrane environments. Isoflurane introduced into the aqueous phase readily partitions into the lipid membrane and the membrane-bound protein. Specifically, isoflurane binds persistently to three classes of sites in the nAChR transmembrane domain: (i) An isoflurane dimer occludes the pore, contacting residues identified by previous mutagenesis studies; analogous behavior is observed in GLIC. (ii) Several nAChR subunit interfaces are also occupied, in a site suggested by photoaffinity labeling and thought to positively modulate the receptor; these sites are not occupied in GLIC. (iii) Isoflurane binds to the subunit centers of both nAChR alpha chains and one of the GLIC chains, in a site that has had little experimental targeting. Interpreted in the context of existing structural and physiological data, the present MD results support a multisite model for the mechanism of receptor-channel modulation by anesthetics.}, doi = {10.1073/pnas.1008534107}, author = {Grace Brannigan and David N LeBard and J{\'e}r{\^o}me H{\'e}nin and Roderic G Eckenhoff and Michael L Klein} } @article {2009|1959, title = {Joint Evolutionary Trees: A Large-Scale Method To Predict Protein Interfaces Based on Sequence Sampling}, journal = {Plos Comput. Biol.}, volume = {5}, number = {1}, year = {2009}, month = {jan}, pages = {e1000267}, doi = {10.1371/journal.pcbi.1000267}, url = {http://dx.doi.org/10.1371\%2Fjournal.pcbi.1000267}, author = {Engelen, Stefan and Trojan, Ladislas A. and S Sacquin-Mora and Lavery, Richard and Carbone, Alessandra} } @article {2008|1970, title = {Embedded cholesterol in the nicotinic acetylcholine receptor}, journal = {Proc. Natl. Acad. Sci. U.s.a.}, volume = {105}, number = {38}, year = {2008}, pages = {14418{\textendash}14423}, publisher = {Center for Molecular Modeling, Department of Chemistry, University of Pennsylvania, Philadelphia, PA 19104, USA. grace@cmm.upenn.edu}, abstract = {The nicotinic acetylcholine receptor (nAChR) is a cation-selective channel central to both neuronal and muscular processes and is considered the prototype for ligand-gated ion channels, motivating a structural determination effort that spanned several decades [Unwin N (2005) Refined structure of the nicotinic acetylcholine receptor at 4 A resolution. J Mol Biol 346:967-989]. Purified nAChR must be reconstituted in a mixture containing cholesterol to function. Proposed modes of interaction between cholesterol and the protein range from specific binding to indirect membrane-mediated mechanisms. However, the underlying cause of nAChR sensitivity to cholesterol remains controversial, in part because the vast majority of functional studies were conducted before a medium resolution structure was reported. We show that the nAChR contains internal sites capable of containing cholesterol, whose occupation stabilizes the protein structure. We detect sites at the protein-lipid interface as conventionally predicted from functional data, as well as deeply buried sites that are not usually considered. Molecular dynamics simulations reveal that occupation of both superficial and deeply buried sites most effectively preserves the experimental structure; the structure collapses in the absence of bound cholesterol. In particular, we find that bound cholesterol directly supports contacts between the agonist-binding domain and the pore that are thought to be essential for activation of the receptor. These results likely apply to those other ion channels within the Cys-loop superfamily that depend on cholesterol, such as the GABA receptor.}, doi = {10.1073/pnas.0803029105}, author = {Grace Brannigan and J{\'e}r{\^o}me H{\'e}nin and Richard Law and Roderic G Eckenhoff and Michael L Klein} } @inbook {2008|1565, title = {Recombination and Meiosis : Models, Means and Evolution Coll. Genome Dynamics \& Stability}, booktitle = {Genome Dynamics \& Stability}, volume = {3}, year = {2008}, pages = {65{\textendash}84}, publisher = {Springer Verlag Berlin Heidleberg}, organization = {Springer Verlag Berlin Heidleberg}, chapter = {Searching for Homology by Filaments of RecA-like Proteins}, author = {Chantal Pr{\'e}vost}, editor = {Richard Egel and Dirk-Henner Lankenau} } @inbook {2008|1651, title = {Searching for Homology by Filaments of RecA-like Proteins}, booktitle = {Genome Dynamics \& Stability}, volume = {Recombination and Meiosis. Models, Means and Evolution}, number = {3}, year = {2008}, pages = {65{\textendash}89}, publisher = {Springer Verlag}, organization = {Springer Verlag}, edition = {Richard Egel and Dirk-Henner Lankenau}, address = {Berlin Heidelberg}, abstract = {

The recombinase proteins of the RecA family perform tasks that are essential for cell survival and for the maintenance of genetic diversity. They are able to rearrange genes in new combinations and to repair DNA double-strand breaks in an almost error-free fashion. Their function in homologous recombination is performed in an original way that has no equivalent in the DNA processing machinery: They form long helical filaments on a target DNA, capable of recognizing homologous DNA sequences in the genome and of exchanging DNA strands. How the DNA sequences are recognized during this process and how the DNA strands are exchanged remain matters of investigation. This chapter reviews the information that has been accumulated on recognition and strand exchange, together with the models that aim at organizing this data, viewed at different levels: that of the nucleus, the molecule, or the atom. Altogether, a picture begins to emerge on a multiscale dimension, which presents the search for homology as a complex process with important dynamic components.

}, author = {Chantal Pr{\'e}vost}, editor = {Richard Egel and Dirk Henner-Lankenau} } @article {2007|1477, title = {Three hydrolases and a transferase: Comparative analysis of active-site dynamics via the BioSimGrid database}, journal = {Journal of Molecular Graphics \& Modelling}, volume = {25}, number = {6}, year = {2007}, month = {mar}, pages = {896{\textendash}902}, author = {Tai, Kaihsu and Marc Baaden and Murdock, Stuart and Wu, Bing and Ng, Muan Hong and Johnston, Steven and Boardman, Richard and Fangohr, Hans and Cox, Katherine and Essex, Jonathan W. and Sansom, Mark S. P.} } @conference {2006, title = {PHYS 4-Applications of activated methods to proteins and materials science}, booktitle = {Abstracts of Papers of the American Chemical Society}, volume = {232}, year = {2006}, author = {Mousseau, Normand and Barkema, Gerard T. and Chubynsky, Mykyta V. and Philippe Derreumaux and El-Mellouhi, Fedwa and Vocks, Henk} } @article {2006|1604, title = {Probing a model of a {GPCR}/ligand complex in an explicit membrane environment: The human cholecystokinin-1 receptor}, journal = {Biophys. J.}, volume = {90}, number = {4}, year = {2006}, pages = {1232{\textendash}1240}, abstract = {A three-dimensional model structure of a complex formed by a G-protein-coupled receptor (GPCR) and an agonist ligand is probed and refined using molecular-dynamics simulations and free energy calculations in a realistic environment. The model of the human receptor of cholecystokinin associated to agonist ligand CCK9 was obtained from a synergistic procedure combining site-directed mutagenesis experiments and in silico modeling. The 31-ns molecular-dynamics simulation in an explicit membrane environment indicates that both the structure of the receptor and its interactions with the ligand are robust. Whereas the secondary structure of the {alpha}-helix bundle is well preserved, the region of the intracellular loops exhibits a significant flexibility likely to be ascribed to the absence of G-protein subunits in the model. New insight into the structural features of the binding pocket is gained, in particular, the interplay of the ligand with both the receptor and internal water molecules. Water-mediated interactions are shown to participate in the binding, hence, suggesting additional site-directed mutagenesis experiments. Accurate free energy calculations on mutated ligands provide differences in the receptor-ligand binding affinity, thus offering a direct, quantitative comparison to experiment. We propose that this detailed consistency-checking procedure be used as a routine refinement step of in vacuo GPCR models, before further investigation and application to structure-based drug design.}, url = {http://www.biophysj.org/cgi/content/abstract/90/4/1232}, author = {J{\'e}r{\^o}me H{\'e}nin and Maigret, B. and Mounir Tarek and Escrieut, C. and Fourmy, D. and Christophe Chipot} } @article {2006|1514, title = {Protein Peeling 2: a web server to convert protein structures into series of protein units}, journal = {Nucleic Acids Res.}, volume = {34}, number = {Sp. Iss. SI}, year = {2006}, month = {jul}, pages = {W75-W78}, author = {Gelly, J. -C. and Etchebest, C. and Hazout, S. and de Brevern, A. G.} } @article {2005|2011, title = {{M}olecular tuning of fast gating in pentameric ligand-gated ion channels}, journal = {Proc. Natl. Acad. Sci. U.s.a.}, volume = {102}, number = {50}, year = {2005}, month = {dec}, pages = {18207{\textendash}18212}, publisher = {National Acad Sciences}, author = {Grutter, T. and de Carvalho, L. P. and Dufresne, V. and Antoine Taly and Edelstein, S. J. and Jean-Pierre Changeux} } @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 {1995|1632, title = {Investigation of the conformational properties of a {$\beta$}-(1-3) branched {$\beta$}-(1-6) heptasacchardie elicitor and its analogues by internal coordinate stochastic dynamics}, journal = {Carbohydr. Res.}, volume = {279}, year = {1995}, pages = {41{\textendash}57}, author = {Michael G. Petukhov and Alexey K Mazur and Lyudmila A. Elyakova} } @article {1992|1594, title = {Multiple attack in the mechanism of endoglucanase action}, journal = {Bioorg. Chem.}, volume = {18}, year = {1992}, pages = {1141{\textendash}1163}, author = {P. V. Bezukladnikov and L. A. Elyakova and Alexey K Mazur} } @article {1989|1644, title = {A new approach to the modelling of the structure and dynamics of biomacromolecules and their complexes}, journal = {Doklady. Biophysics}, volume = {304}, year = {1989}, pages = {456{\textendash}460}, author = {Alexey K Mazur and R. A. Abagyan and G. B. Elyakov} } @article {1988|1627, title = {Model of spatial random movement of depolymerase when interacting with the substrate}, journal = {Biophysics}, volume = {23}, year = {1988}, pages = {417{\textendash}421}, author = {Alexey K Mazur and M. G. Petukhov and L. A. Elyakova} } @article {1986, title = {Active sites of the endo-beta-1,3-glucanases from Spisula sacchalinensis and Chlyamys albidys}, journal = {Bioorg. Chem.}, volume = {12}, year = {1986}, pages = {1478{\textendash}1483}, author = {N. I. Nazarova and Alexey K Mazur and L. A. Elyakova} } @article {1985, title = {Oligomer distribution of depolymerase digests: Comparison of theory and experiments}, journal = {Febs Lett.}, volume = {192}, year = {1985}, pages = {43{\textendash}46}, author = {Alexey K Mazur and N. I. Nazarova and L. A. Elyakova} } @article {1983, title = {Kinetics of glucose accumulation during depolimerization of polysaccharides by enzymes with different mechanisms of action}, journal = {Mol. Biol.}, volume = {17}, year = {1983}, pages = {101{\textendash}111}, author = {Alexey K Mazur and L. A. Elyakova} } @article {1982, title = {Mathematical modelling of endoglucanase-catalysed hydrolysis of a linear polysaccharide}, journal = {Mol. Biol.}, volume = {16}, year = {1982}, pages = {499{\textendash}510}, author = {L. A. Elyakova and Alexey K Mazur} }