PspG, a New Member of the Yersinia enterocolitica Phage Shock Protein Regulon

AUTOR(ES)

Green, Rebecca C.

FONTE

American Society for Microbiology

RESUMO

The Yersinia enterocolitica phage shock protein (Psp) system is induced when the Ysc type III secretion system is produced or when only the YscC secretin component is synthesized. Some psp null mutants have a growth defect when YscC is produced and a severe virulence defect in animals. The Y. enterocolitica psp locus is made up of two divergently transcribed cistrons, pspF and pspABCDycjXF. pspA operon expression is dependent on RpoN (σ54) and the enhancer-binding protein PspF. Previous data indicated that PspF also controls at least one gene that is not part of the psp locus. In this study we describe the identification of pspG, a new member of the PspF regulon. Predicted RpoN-binding sites upstream of the pspA genes from different bacteria have a common divergence from the consensus sequence, which may be a signature of PspF-dependent promoters. The Y. enterocolitica pspG gene was identified because its promoter also has this signature. Like the pspA operon, pspG is positively regulated by PspF, negatively regulated by PspA, and induced in response to the production of secretins. Purified His6-PspF protein specifically interacts with the pspA and pspG control regions. A pspA operon deletion mutant has a growth defect when the YscC secretin is produced and a virulence defect in a mouse model of infection. These phenotypes were exacerbated by a pspG null mutation. Therefore, PspG is the missing component of the Y. enterocolitica Psp regulon that was previously predicted to exist.

Documentos Relacionados

• Phage Shock Protein PspA of Escherichia coli Relieves Saturation of Protein Export via the Tat Pathway
• The Yersinia enterocolitica Phospholipase Gene yplA Is Part of the Flagellar Regulon
• Identification of Inducers of the Yersinia enterocolitica Phage Shock Protein System and Comparison to the Regulation of the RpoE and Cpx Extracytoplasmic Stress Responses
• Involvement of stress protein PspA (phage shock protein A) of Escherichia coli in maintenance of the protonmotive force under stress conditions.
• HreP, an In Vivo-Expressed Protease of Yersinia enterocolitica, Is a New Member of the Family of Subtilisin/Kexin-Like Proteases