En savoir plus

Au sein de l'équipe SporAlim et co-encadrée par Catherine Duport, Luc Dedieu et Philippe Schmitt, le travail de doctorat de Fella a porté sur la "caractérisation du thiol protéome chez Bacillus cereus". La soutenance se déroulera en présentiel avec jauge réduite mais sera accessible par visioconférence

adresse de connexion :  https://bbb.univ-avignon.fr/b/ded-fbb-xpj

Résumé de la thèse:

Bacillus cereus is a foodborne pathogen endowed with the ability to sense and adapt to changing environments, particularly to the presence and absence of oxygen. In response to oxygen availability, the bacterium adjusts its central metabolism to maintain cellular redox homeostasis. Cysteine residues are central elements of redox homeostasis, owing to the properties of thiol (SH) groups. The set of proteins with cysteine residues whose redox state can be reversibly modified constitutes the thiol proteome.

In order to understand to what extent the thiol proteome contributes to the redox homeostasis of B. cereus ATCC14579 during its aerobic respiratory and its anaerobic fermentative growth, we have implemented and performed a redox proteomics approach based on the differential alkylation of cysteines and the detection of alkylated cysteines by tandem mass spectrometry (LC-MS/MS). Monitoring the reversible redox status of cysteines throughout the exponential growth phase allowed us to highlight the specificity of the thiol proteome, as well as its growth-phase dependence and its dynamics in response to oxygenation conditions.

This work is the first study of the thiol proteome of B. cereus. It provided a mapping of the aerobic and anaerobic thiol proteomes, serving as references for further studies aiming to elucidate the cellular adaptation of B. cereus to environmental changes.​