Title :

A Salmonella type three secretion effector/chaperone complex adopts a hexameric ring-like structure

Author(s) :

Roblin, Pierre [Auteur]
Synchrotron SOLEIL [SSOLEIL]
Unité de recherche sur les Biopolymères, Interactions Assemblages [BIA]
Dewitte, Frederique [Auteur]
Unité de Glycobiologie Structurale et Fonctionnelle - UMR 8576 [UGSF]
Villeret, Vincent [Auteur]
Unité de Glycobiologie Structurale et Fonctionnelle UMR 8576 [UGSF]
Biondi, Emanuele G. [Auteur]
Unité de Glycobiologie Structurale et Fonctionnelle - UMR 8576 [UGSF]
Bompard, Coralie [Auteur]
Unité de Glycobiologie Structurale et Fonctionnelle UMR 8576 [UGSF]

Journal title :

Journal of Bacteriology

Abbreviated title :

J. Bacteriol.

Volume number :

197

Pages :

688-698

Publication date :

2015-02-15

ISSN :

1098-5530

English keyword(s) :

Protein Structure, Tertiary
Molecular Chaperones
Sigma Factor
Bacterial Secretion Systems
Models, Molecular
Scattering, Small Angle
Salmonella typhimurium
Bacterial Proteins

HAL domain(s) :

Chimie/Chimie théorique et/ou physique

English abstract : [en]

Many bacterial pathogens use type three secretion systems (T3SS) to inject virulence factors, named effectors, directly into the cytoplasm of target eukaryotic cells. Most of the T3SS components are conserved among plant ...
Show more >Many bacterial pathogens use type three secretion systems (T3SS) to inject virulence factors, named effectors, directly into the cytoplasm of target eukaryotic cells. Most of the T3SS components are conserved among plant and animal pathogens, suggesting a common mechanism of recognition and secretion of effectors. However, no common motif has yet been identified for effectors allowing T3SS recognition. In this work, we performed a biochemical and structural characterization of the Salmonella SopB/SigE chaperone/effector complex by small-angle X-ray scattering (SAXS). Our results showed that the SopB/SigE complex is assembled in dynamic homohexameric-ring-shaped structures with an internal tunnel. In this ring, the chaperone maintains a disordered N-terminal end of SopB molecules, in a good position to be reached and processed by the T3SS. This ring dimensionally fits the ring-organized molecules of the injectisome, including ATPase hexameric rings; this organization suggests that this structural feature is important for ATPase recognition by T3SS. Our work constitutes the first evidence of the oligomerization of an effector, analogous to the organization of the secretion machinery, obtained in solution. As effectors share neither sequence nor structural identity, the quaternary oligomeric structure could constitute a strategy evolved to promote the specificity and efficiency of T3SS recognition.Show less >

Language :

Anglais

Audience :

Non spécifiée

Administrative institution(s) :

CNRS
Université de Lille

Collections :

• Unité de Glycobiologie Structurale et Fonctionnelle (UGSF) - UMR 8576

Research team(s) :

Plant Storage Polysaccharides
Biologie structurale et intégrative

Submission date :

2020-02-12T15:11:27Z
2021-03-11T15:08:36Z