The structural organization of the N-terminus domain of SopB, a virulence factor of Salmonella, depends on the nature of its protein partners.

TitleThe structural organization of the N-terminus domain of SopB, a virulence factor of Salmonella, depends on the nature of its protein partners.
Publication TypeJournal Article
Year of Publication2013
AuthorsRoblin, P., P. Lebrun, P. Rucktooa, F. Dewitte, Z. Lens, V. Receveur-Brechot, V. Raussens, V. Villeret, and C. Bompard
JournalBiochim Biophys Acta
Volume1834
Issue12
Pagination2564-72
Date Published2013 Dec
ISSN0006-3002
KeywordsBacterial Proteins, Molecular Chaperones, Protein Structure, Quaternary, Protein Structure, Secondary, Protein Structure, Tertiary, Salmonella typhimurium, Sigma Factor
Abstract

The TTSS is used by Salmonella and many bacterial pathogens to inject virulence factors directly into the cytoplasm of target eukaryotic cells. Once translocated these so-called effector proteins hijack a vast array of crucial cellular functions to the benefit of the bacteria. In the bacterial cytoplasm, some effectors are stabilized and maintained in a secretion competent state by interaction with specific type III chaperones. In this work we studied the conformation of the Chaperone Binding Domain of the effector named Salmonella Outer protein B (SopB) alone and in complex with its cognate chaperone SigE by a combination of biochemical, biophysical and structural approaches. Our results show that the N-terminus part of SopB is mainly composed by α-helices and unfolded regions whose organization/stabilization depends on their interaction with the different partners. This suggests that the partially unfolded state of this N-terminal region, which confers the adaptability of the effector to bind very different partners during the infection cycle, allows the bacteria to modulate numerous host cells functions limiting the number of translocated effectors.

DOI10.1016/j.bbapap.2013.09.014
Alternate JournalBiochim. Biophys. Acta
PubMed ID24075929