A protein secreted by the Salmonella type III secretion system controls needle filament assembly.
Elife
; 72018 07 17.
Article
em En
| MEDLINE
| ID: mdl-30015613
ABSTRACT
Type III protein secretion systems (T3SS) are encoded by several pathogenic or symbiotic bacteria. The central component of this nanomachine is the needle complex. Here we show in a Salmonella Typhimurium T3SS that assembly of the needle filament of this structure requires OrgC, a protein encoded within the T3SS gene cluster. Absence of OrgC results in significantly reduced number of needle substructures but does not affect needle length. We show that OrgC is secreted by the T3SS and that exogenous addition of OrgC can complement a ∆orgC mutation. We also show that OrgC interacts with the needle filament subunit PrgI and accelerates its polymerization into filaments in vitro. The structure of OrgC shows a novel fold with a shared topology with a domain from flagellar capping proteins. These findings identify a novel component of T3SS and provide new insight into the assembly of the type III secretion machine.
Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Salmonella typhimurium
/
Proteínas de Bactérias
/
Sistemas de Secreção Tipo III
Tipo de estudo:
Prognostic_studies
Idioma:
En
Revista:
Elife
Ano de publicação:
2018
Tipo de documento:
Article
País de afiliação:
Estados Unidos