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Launay, G.

Publications and source records attributed to Launay, G..

6 recordsLinked to original sources

Extending the MAD Toolbox: New Polymer Builder and Enhanced Martini Database

The MArtini Database (MAD) web server (https://mad.ens-lyon.fr/) has been updated with new tools, models, and capabilities to support a broader range of molecular systems for the Martini coarse-grained (CG) force field. The most notable addition is the MAD:Polymer Builder, enabling the automated construction of CG polymer models with varying architectures and complexities. The server now incorporates the latest developments in Martini 3, providing enhanced control within the MAD:Molecule Builder over the conversion of all-atom structures into CG representations, including the implementation of G[o]Martini 3 for protein complexes and water-protein interaction biases. The MAD:Polymer Builder and MAD:Molecule Builder are both adapted to work with intrinsically disordered proteins and domains. Substantial progress has been made in expanding the MAD:Database, making a growing library of Martini-ready compounds readily accessible across the entire MAD ecosystem. These advances position MAD as a comprehensive and evolving platform for the preparation of diverse systems in CG molecular simulations.

bioinformatics↗

Rational Prediction of PROTAC-compatible Protein-Protein Interfaces by Molecular Docking

Proteolysis targeting chimeras (PROTACS) are heterobifunctional ligands that mediate the interaction between a protein target and an E3 ligase, resulting in a ternary complex whose interaction with the ubiquitination machinery leads to target degradation. This technology is emerging as an exciting new avenue for therapeutic development, with several PROTACS currently undergoing clinical trials targeting cancer. Here, we describe a general and computationally efficient methodology combining restraint-based docking, energy-based rescoring, and a filter based on minimal solvent-accessible surface distance to produce PROTAC-compatible PPIs suitable for when there is no a priori known PROTAC ligand. In a benchmark employing a manually curated dataset of 13 ternary complex crystals, we achieved accuracy of 92% when starting from bound structures, and 77% when starting from unbound structures, respectively. Our method only requires that the ligand-bound structures of the monomeric forms of the E3 ligase and target proteins be given to run, making it general, accurate and highly efficient, with the ability to impact early stage PROTAC-based drug design campaigns where no structural information about the ternary complex structure is available.

bioinformatics↗

Coarse-graining made easy with the MArtini Database Server

The MArtini Database (MAD - www.mad.ibcp.fr) is a web server designed for the sharing structures and topologies of molecules parameterized with the Martini coarse-grained (CG) force field. MAD can also convert atomistic structures into CG structures and prepare complex systems (including proteins, lipids etc.) for molecular dynamics (MD) simulations at the CG level. It is dedicated to the generation of input files for Martini 3, the most recent version of this popular CG force field. Specifically, the MAD server currently includes tools to submit or retrieve CG models of a wide range of molecules (lipids, carbohydrates, nanoparticles, etc.), transform atomistic protein structures into CG structures and topologies, with fine control on the process and assemble biomolecules into large systems and deliver all files necessary to start simulations in the GROMACS MD engine.

biophysics↗

Targeted-Antibacterial-Plasmids (TAPs) combining conjugation and CRISPR /Cas systems achieve strain-specific antibacterial activity

The global emergence of drug-resistant bacteria leads to the loss of efficacy of our antibiotics arsenal and severely limits the success of currently available treatments. Here, we developed an innovative strategy based on Targeted-Antibacterial-Plasmids (TAPs) that use bacterial conjugation to deliver CRISPR/Cas systems exerting a strain-specific antibacterial activity. TAPs are highly versatile as they can be directed against any specific genomic or plasmid DNA using the custom algorithm (CSTB) that identifies appropriate targeting spacer sequences. We demonstrate the ability of TAPs to induce strain-selective killing by introducing lethal double strand breaks (DSBs) into the targeted genomes. TAPs directed against a plasmid-born carbapenem resistance gene efficiently resensitise the strain to the drug. This work represents an essential step towards the development of an alternative to antibiotic treatments, which could be used for in situ microbiota modification to eradicate targeted resistant and/or pathogenic bacteria without affecting other non-targeted bacterial species.

microbiology↗

Rescoring ensembles of protein-protein docking poses using consensus approaches

Scoring is a challenging step in protein-protein docking, where typically thousands of solutions are generated. Successful scoring is more often based on physicochemical evaluation of the generated interfaces and/or statistical potentials that reproduce known interface properties. Another route is offered by consensus-based rescoring, where the set of solutions is used to build statistics in order to identify recurrent solutions. We explore several ways to perform consensus-based rescoring on the ZDOCK decoy set for Benchmark 4. We show that the information of the interface size is critical for successful rescoring. We combine consensus-based rescoring with the ZDOCK native scoring function and show that this improves the initial results.

bioinformatics↗

A non-parametric method to compute protein-protein and protein-ligands interfaces. Application to HIV-2 protease-inhibitors complexes

MotivationThe accurate description of interfaces is needed to identify which residues interact with another molecule or macromolecule. In addition, a data structure is required to compare interfaces within or between families of protein-protein or protein-ligands complexes. In order to avoid many unwanted comparisons, we looked for a parameter free computation of interfaces. This need appeared at the occasion of bioinformatics studies by our research team focusing on HIV-2 protease (PR2) resistance to its inhibitors.\n\nResultsWe designed the PPIC software (Protein Protein Interface Computation). It offers three methods of computation of interfaces: (1) our original parameter free method, (2) the Voronoi tessellation approach, and (3) the cutoff distance method. For the latter, we suggest on the basis of 1050 dimers protein-protein interfaces that the optimal cutoff distance is 3.7 [A], or 3.6 [A] for a set of 18 PR2-ligand interfaces. We found at most 17 contact residues with PR2 ligands.\n\nAvailabilityFree binaries and documentation are available through a software repository located at http://petitjeanmichel.free.fr/itoweb.petitjean.freeware.html\n\nContactpetitjean.chiral@gmail.com, michel.petitjean@univ-paris-diderot.fr

bioinformatics↗