Open AccessAcid stress responses in enterobacteria
Author(s) -
Bearson Shawn,
Bearson Bradley,
Foster John W
Publication year - 1997
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.1574-6968.1997.tb10238.x
Subject(s) - shigella flexneri , shigella , biogenesis , escherichia coli , sigma factor , salmonella , biology , enterobacteriaceae , pathogenesis , signal transduction , rpos , microbiology and biotechnology , bacteria , biochemistry , genetics , gene , immunology , gene expression , promoter , rna polymerase
The enteric microorganisms Salmonella typhimurium , Escherichia coli and Shigella flexneri prefer to grow in neutral pH environments. They nevertheless experience dramatic pH fluctuations in nature and during pathogenesis. In response to environmental encounters with acid, these organisms have evolved complex, inducible acid survival strategies. Regulatory features include an alternative sigma factor (σ S ), 2‐component signal transduction systems (PhoP/Q; MviA/?) and the major iron regulatory protein Fur. Specific survival mechanisms include emergency pH homeostasis by inducible amino acid decarboxylases and probable roles for DNA repair, chaparonins, membrane biogenesis as well as others that remain poorly defined. Continued study of acid survival in these organisms will provide general insights regarding stress management and will have a direct impact on our understanding of pathogenesis.