Premium
Identification of qseEGF genetic locus and its roles in controlling hemolytic activity and invasion in fish pathogen Edwardsiella tarda
Author(s) -
Xiao Jingfan,
Chen Tao,
Yang Minjun,
Zhang Yuanxing,
Wang Qiyao
Publication year - 2012
Publication title -
letters in applied microbiology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.698
H-Index - 110
eISSN - 1472-765X
pISSN - 0266-8254
DOI - 10.1111/j.1472-765x.2012.03260.x
Subject(s) - edwardsiella tarda , biology , pathogen , microbiology and biotechnology , locus (genetics) , identification (biology) , fish <actinopterygii> , human pathogen , gene , genetics , ecology , fishery
Abstract Aims: The aims of this study were to reveal the roles of the gene locus qseEGF in the pathogenesis of Edwardsiella tarda . Methods and Results: Genome sequencing of fish pathogen E. tarda EIB202 reveals that the gene locus qseEGF , which encodes a novel two‐component system QseEF, were located in E. tarda . The transcription of qseE , qseF and qseG was firstly characterized to be cotranscribed by reverse‐transcribed PCR (RT‐PCR). The mutant strains Δ qseE , Δ qseF and Δ qseG were constructed with in‐frame deletion strategy. Compared with the wild type, all of the mutants showed attenuated virulence and impaired intracellular survival capabilities. Deletion in qseE , qseF and qseG resulted in different effects on hemolysin production in E. tarda . qRT‐PCR results indicated that QseEF played a role in regulation of secretion systems, which in turn affected the virulence of E. tarda . Conclusions: The results manifested that QseEF system affected the virulence in E. tarda EIB202 by controlling the secretion system and hemolysin production. QseE, QseG and QseF in E. tarda serve for the physiological fitness and pathogenesis related to the bacterial survival in macrophage and in vivo of fish. Significance and Impact: The present results suggested that the important role of two‐component system QseEF in regulation of E. tarda pathogenesis and its potential for attenuated live vaccine construction.