Etudes structurales de la défensine AhPDF1 de la plante Arabidopsis halleri impliquée dans la tolérance au zinc

Abstract : My thesis focuses on the AhPDF1 plant defensin from Arabidopsis halleri. AhPDF1 is a 51-residue, cysteine-rich protein involved in the plant defense, and playing an antifungal role. AhPDF1 defensin has eight cysteins involved in its four disulfide bridges, and presents a folding in CSαβ. Recent work on AhPDF1 allowed to identify a new function : the tolerance to heavy metals, especially zinc tolerance. The overall objective of the project that fits my thesis is to understand, at the atomic level and in relation to the oxidation state of cysteins, the mechanism by which the plant defensins confer zinc tolerance. In a major part of my thesis I worked on the production of AhPDF1 defensin first in Escherichia coli and in Pichia pastoris. Then, I developed the chemical synthesis of AhPDF1 and optimized the most delicate step of the oxidative folding. After producing AhPDF1 defensin in sufficient quantity and quality, I realized its structural study by NMR. Furthermore, this structure was used as starting structure, for modeling by homology all other defensins currently identified from Arabidopsis halleri and Arabidopsis thaliana. Finally, I learnt how to master the conditions that maintain the protein in a partially reduced state in order to achieve the first assay of zinc chelation with defensin.
Document type :
Theses
Complete list of metadatas

Cited literature [176 references]  Display  Hide  Download

https://tel.archives-ouvertes.fr/tel-01058780
Contributor : Abes Star <>
Submitted on : Thursday, August 28, 2014 - 10:33:09 AM
Last modification on : Wednesday, June 27, 2018 - 8:24:02 AM
Long-term archiving on : Tuesday, April 11, 2017 - 8:44:44 PM

File

fanny.meindre_3420.pdf
Version validated by the jury (STAR)

Identifiers

  • HAL Id : tel-01058780, version 1

Collections

Citation

Fanny Meindre. Etudes structurales de la défensine AhPDF1 de la plante Arabidopsis halleri impliquée dans la tolérance au zinc. Sciences agricoles. Université d'Orléans, 2013. Français. ⟨NNT : 2013ORLE2064⟩. ⟨tel-01058780⟩

Share

Metrics

Record views

356

Files downloads

851