Open AccessIdentification and characterization of a type III secretion‐associated chaperone in the type III secretion system 1 of Vibrio parahaemolyticus
Author(s) -
Akeda Yukihiro,
Okayama Kanna,
Kimura Tomomi,
Dryselius Rikard,
Kodama Toshio,
Oishi Kazunori,
Iida Tetsuya,
Honda Takeshi
Publication year - 2009
Publication title -
fems microbiology letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.899
H-Index - 151
eISSN - 1574-6968
pISSN - 0378-1097
DOI - 10.1111/j.1574-6968.2009.01607.x
Subject(s) - vibrio parahaemolyticus , secretion , microbiology and biotechnology , type three secretion system , biology , identification (biology) , chemistry , biochemistry , bacteria , genetics , gene , ecology , virulence
Vibrio parahaemolyticus causes human gastroenteritis. Genomic sequencing of this organism has revealed that it has two sets of type III secretion systems, T3SS1 and T3SS2, both of which are important for its pathogenicity. However, the mechanism of protein secretion via T3SSs is unknown. A characteristic of many effectors is that they require specific chaperones for efficient delivery via T3SSs; however, no chaperone has been experimentally identified in the T3SSs of V. parahaemolyticus . In this study, we identified candidate T3SS1‐associated chaperones from genomic sequence data and examined their roles in effector secretion/translocation and binding to their cognate substrates. From these experiments, we concluded that there is a T3S‐associated chaperone, VecA, for a cytotoxic T3SS1‐dependent effector, VepA. Further analysis using pulldown and secretion assays characterized the chaperone‐binding domain encompassing the first 30–100 amino acids and an amino terminal secretion signal encompassing the first 5–20 amino acids on VepA. These findings will provide a strategy to clarify how the T3SS1 of V. parahaemolyticus secretes its specific effectors.