Skip to Main content Skip to Navigation
Theses

Recalage flexible de modèles moléculaires dans les reconstructions 3D de microscopie électronique

Abstract : Today, macromolecular crystallography commonly produces molecular models at atomic resolution. However, this technique is particularly difficult to implement in the cases of large complexes. Electron microscopy allows for the visualization of large particles under conditions similar to those in vivo. However, the resolution of three-dimensional reconstructions obtained by electron microscopy does not allow, in general, the direct interpretation of molecular structures, a necessary step in understanding biological problems. Therefore, it is natural to try to combine information provided by these two techniques to characterize the structure of macromolecular assemblies. The idea is to place the molecular models determined by crystallography inside electron microscopy 3D reconstructions, and compare the electron density associated to the 3D reconstruction with an electron density calculated from the models. The numerical problem is the determination and the optimization of the variables that specify the positions of the models, considered as rigid body, inside the assembly. This simple idea has led to the development of a method called fitting. This thesis aims to provide biologists with a tool, based on the method of fitting, that allows them to build pseudo-molecular models associated to the assemblies produced by electron microscopy. The software resulting from this work, named VEDA, has a user-friendly graphical environment, includes the possibility of flexible fitting, and implements a powerful calculation core (fast computation, treatment of complex symmetry, use of large volumes, etc.). Tested on dozens of real cases with experimental data sets, VEDA is now fully functional and is used by a growing number of researchers in France and abroad. All of the users have recognized ease of use, stability, speed, and quality of results of VEDA. STAR
Complete list of metadata

Cited literature [76 references]  Display  Hide  Download

https://tel.archives-ouvertes.fr/tel-00631858
Contributor : ABES STAR :  Contact
Submitted on : Thursday, October 13, 2011 - 11:22:25 AM
Last modification on : Saturday, March 26, 2022 - 3:17:27 AM
Long-term archiving on: : Saturday, January 14, 2012 - 2:26:20 AM

File

These_Gael_Goret_valide.pdf
Version validated by the jury (STAR)

Identifiers

  • HAL Id : tel-00631858, version 1

Collections

Citation

Gaël Goret. Recalage flexible de modèles moléculaires dans les reconstructions 3D de microscopie électronique. Biologie structurale [q-bio.BM]. Université de Grenoble, 2011. Français. ⟨NNT : 2011GRENV040⟩. ⟨tel-00631858⟩

Share

Metrics

Record views

322

Files downloads

319