Phage Shock Protein PspA of Escherichia coli Relieves Saturation of Protein Export via the Tat Pathway
AUTOR(ES)
DeLisa, Matthew P.
FONTE
American Society for Microbiology
RESUMO
Overexpression of either heterologous or homologous proteins that are routed to the periplasm via the twin-arginine translocation (Tat) pathway results in a block of export and concomitant accumulation of the respective protein precursor in the cytoplasm. Screening of a plasmid-encoded genomic library for mutants that confer enhanced export of a TorA signal sequence (ssTorA)-GFP-SsrA fusion protein, and thus result in higher cell fluorescence, yielded the pspA gene encoding phage shock protein A. Coexpression of pspA relieved the secretion block observed with ssTorA-GFP-SsrA or upon overexpression of the native Tat proteins SufI and CueO. A similar effect was observed with the Synechocystis sp. strain PCC6803 PspA homologue, VIPP1, indicating that the role of PspA in Tat export may be phylogenetically conserved. Mutations in Tat components that completely abolish export result in a marked induction of PspA protein synthesis, consistent with its proposed role in enhancing protein translocation via Tat.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=305757Documentos Relacionados
- Involvement of stress protein PspA (phage shock protein A) of Escherichia coli in maintenance of the protonmotive force under stress conditions.
- The PspA Protein of Escherichia coli Is a Negative Regulator of ς54-Dependent Transcription
- Phage shock protein, a stress protein of Escherichia coli.
- Effects of PspA and Antibodies to PspA on Activation and Deposition of Complement on the Pneumococcal Surface
- PspG, a New Member of the Yersinia enterocolitica Phage Shock Protein Regulon