@article {2009|1636, title = {Deforming DNA: from physics to biology}, journal = {Chemphyschem}, volume = {10}, year = {2009}, month = {jul}, pages = {1399{\textendash}404}, abstract = {

The DNA double helix has become a modern icon which symbolizes our understanding of the molecular basis of life. It is less widely recognized that the double helix proposed by Watson and Crick more than half a century ago is a remarkably adaptable molecule that can undergo major conformational rearrangements without being irreversibly damaged. Indeed, DNA deformation is an intrinsic feature of many of the biological processes in which it is involved. Over the last two decades, single-molecule experiments coupled with molecular modeling have transformed our understanding of DNA flexibility, while the accumulation of high-resolution structures of DNA-protein complexes have demonstrated how organisms can exploit this property as a useful feature for preserving, reading, replicating, and packaging the genetic message. In this Minireview we summarize the information now available on the extreme\–and the less extreme\–deformations of the double helix.

}, doi = {10.1002/cphc.200900253}, author = {Chantal Pr{\'e}vost and M. Takahashi and Richard Lavery} } @article {2008|1710, title = {Identification of Protein Interaction Partners and Protein-Protein Interaction Sites}, journal = {J. Mol. Biol.}, volume = {382}, number = {5}, year = {2008}, pages = {1276{\textendash}1289}, doi = {10.1016/j.jmb.2008.08.002}, author = {S Sacquin-Mora and Carbone, A. and Richard Lavery} } @conference {2007|1517, title = {Atomistic modeling of the membrane-embedded synaptic fusion complex: a grand challenge project on the DEISA HPC infrastructure}, booktitle = {ParCo 2007, Parallel Computing: Architectures, Algorithms and Applications}, volume = {38}, year = {2007}, pages = {729{\textendash}736}, publisher = {John von Neumann Institute for Computing, Juelich, Germany.}, organization = {John von Neumann Institute for Computing, Juelich, Germany.}, url = {http://www.booksonline.iospress.nl/Content/View.aspx?piid=8468}, author = {E. Krieger and L. Leger and M.P. Durrieu and N. Taib and P. Bond and M. Laguerre and R. Lavery and M.S.P. Sansom and Marc Baaden}, editor = {C.B.G.R. Joubert and F. Peters and T. Lippert and M. Buecker and B. Gibbon and and B. Mohr} } @article {2007|1588, title = {Probing the flexibility of the bacterial reaction center: The wild-type protein is more rigid than two site-specific mutants}, journal = {Biochemistry}, volume = {46}, number = {51}, year = {2007}, month = {dec}, pages = {14960{\textendash}14968}, doi = {10.1021/bi7004416}, author = {S Sacquin-Mora and Sebban, P. and Derrien, V. and Frick, B. and Richard Lavery and Alba-Simionesco, C.} } @inbook {2007|1564, title = {There{\textquoteright}s plenty of room in the middle: multi-scale modelling of biological systems}, year = {2007}, pages = {173{\textendash}195}, publisher = {Research signpost, India}, organization = {Research signpost, India}, chapter = {Recent Advances in Protein engineering}, address = {Trivandrum, Kerala, India}, author = {Marc Baaden and R. Lavery}, editor = {A.G. de Brevern} } @article {2006|1619, title = {Investigating the local flexibility of functional residues in hemoproteins}, journal = {Biophys. J.}, volume = {90}, number = {8}, year = {2006}, pages = {2706{\textendash}2717}, doi = {10.1529/biophysj.105.074997}, author = {S Sacquin-Mora and Richard Lavery} } @article {2003|1663, title = {Docking macromolecules with flexible segments}, journal = {J. Comput. Chem.}, volume = {24}, year = {2003}, month = {nov}, pages = {1910{\textendash}20}, abstract = {

We address a major obstacle to macromolecular docking algorithms by presenting a new method that takes into account the induced conformational adjustment of flexible loops situated at a protein/macromolecule interface. The method, MC2, is based on a multiple copy representation of the loops, coupled with a Monte Carlo conformational search of the relative position of the macromolecules and their side chain conformations. The selection of optimal loop conformations takes place during Monte Carlo cycling by the iterative adjustment of the weight of each copy. We describe here the parameterization of the method and trials on a protein-DNA complex of known 3-D structure, involving the Drosophila prd paired domain protein and its target oligonucleotide Wenqing, X. et al., Cell 1995, 80, 639. We demonstrate that our algorithm can correctly configure and position this protein, despite its relatively complex interactions with both grooves of DNA.

}, doi = {10.1002/jcc.10329}, author = {Bastard, Karine and Thureau, Aur{\'e}lien and Richard Lavery and Chantal Pr{\'e}vost} } @article {1999|1600, title = {A molecular model for RecA-promoted strand exchange via parallel triple-stranded helices}, journal = {Biophys. J.}, volume = {77}, year = {1999}, month = {sep}, pages = {1562{\textendash}76}, abstract = {

A number of studies have concluded that strand exchange between a RecA-complexed DNA single strand and a homologous DNA duplex occurs via a single-strand invasion of the minor groove of the duplex. Using molecular modeling, we have previously demonstrated the possibility of forming a parallel triple helix in which the single strand interacts with the intact duplex in the minor groove, via novel base interactions (Bertucat et al., J. Biomol. Struct. Dynam. 16:535-546). This triplex is stabilized by the stretching and unwinding imposed by RecA. In the present study, we show that the bases within this triplex are appropriately placed to undergo strand exchange. Strand exchange is found to be exothermic and to result in a triple helix in which the new single strand occupies the major groove. This structure, which can be equated to so-called R-form DNA, can be further stabilized by compression and rewinding. We are consequently able to propose a detailed, atomic-scale model of RecA-promoted strand exchange. This model, which is supported by a variety of experimental data, suggests that the role of RecA is principally to prepare the single strand for its future interactions, to guide a minor groove attack on duplex DNA, and to stabilize the resulting, stretched triplex, which intrinsically favors strand exchange. We also discuss how this mechanism can incorporate homologous recognition.

}, doi = {10.1016/S0006-3495(99)77004-9}, author = {Bertucat, G and Richard Lavery and Chantal Pr{\'e}vost} } @article {1998|1659, title = {A model for parallel triple helix formation by RecA: single-single association with a homologous duplex via the minor groove}, journal = {J. Biomol. Struct. Dyn.}, volume = {16}, year = {1998}, month = {dec}, pages = {535{\textendash}46}, abstract = {

The nucleoproteic filaments of RecA polymerized on single stranded DNA are able to integrate double stranded DNA in a coaxial arrangement (with DNA stretched by a factor 1.5), to recognize homologous sequences in the duplex and to perform strand exchange between the single stranded and double stranded molecules. While experimental results favor the hypothesis of an invasion of the minor groove of the duplex by the single strand, parallel minor groove triple helices have never been isolated or even modeled, the minor groove offering little space for a third strand to interact. Based on an internal coordinate modeling study, we show here that such a structure is perfectly conceivable when the two interacting oligomers are stretched by a factor 1.5, in order to open the minor groove of the duplex. The model helix presents characteristics that coincide with known experimental data on unwinding, base pair inclination and inter-proton distances. Moreover, we show that extension and unwinding stabilize the triple helix. New patterns of triplet interaction via the minor groove are presented.

}, doi = {10.1080/07391102.1998.10508268}, author = {Bertucat, G and Richard Lavery and Chantal Pr{\'e}vost} } @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 {1995|1681, title = {Efficient conformational space sampling for nucleosides using internal coordinate Monte-Carlo simulations and a modified furanose description}, journal = {J. Comput. Chem.}, volume = {16}, year = {1995}, month = {jun}, pages = {667{\textendash}680}, chapter = {667}, abstract = {

Internal coordinates can be very helpful in modeling large biomacromolecules because freezing stiffer degrees of freedom, such as bond lengths, strongly reduces the number of variables describing the system. This, however, leads to difficulties in treating flexible rings such as the furanose sugars of nucleic acids or the proline residues of proteins, for which internal coordinates are an overcomplete description. We present here a new, internal coordinate furanose model based on the pseudorotational variables phase and amplitude which avoids having to solve a ring closure problem. The choice of a two- rather than a four-variable description is justified by a detailed analysis of molecular dynamic simulations. The efficiency and accuracy of the method are also demonstrated using extensive Monte Carlo simulations. This method of ring treatment is fast and well adapted to macromolecular simulations. (C) 1995 by John Wiley \& Sons, Inc.

}, issn = {0192-8651}, author = {Gabb, HA and Richard Lavery and Chantal Pr{\'e}vost} } @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} }