Open AccessRegulation of Vibrio cholerae Genes Required for Acid Tolerance by a Member of the “ToxR-Like” Family of Transcriptional Regulators
Author(s) -
D. Scott Merrell,
Andrew Camilli
Publication year - 2000
Publication title -
journal of bacteriology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.652
H-Index - 246
eISSN - 1067-8832
pISSN - 0021-9193
DOI - 10.1128/jb.182.19.5342-5350.2000
Subject(s) - biology , vibrio cholerae , operon , gene , transcriptional regulation , escherichia coli , lysine decarboxylase , antiporter , transcription (linguistics) , genetics , transcription factor , biochemistry , cadaverine , bacteria , enzyme , spermidine , linguistics , philosophy , membrane
The ability of the intestinal pathogenVibrio cholerae to undergo an adaptive stress response, known as the acid tolerance response (ATR), was previously shown to enhance virulence. An essential component of the ATR is CadA-mediated lysine decarboxylation. CadA is encoded by the acid- and infection-induced genecadA . Herein,cadA is shown to be the second gene in an operon withcadB , encoding a lysine/cadaverine antiporter.cadC , which is 5′ ofcadB , encodes an acid-responsive, positive transcriptional regulator ofcadBA . Unlike inEscherichia coli ,V. cholerae cadB andcadA are also transcribed monocistronically. Of note, bicistroniccadBA is transcribed at low constitutive levels in an acid- and CadC-independent manner. CadC represents a new member of the “ToxR-like” family of transcriptional regulators inV. cholerae and, in addition, exhibits extensive amino acid and functional similarity toE. coli CadC. The amino-terminal, putative DNA binding domains of ToxR and CadC are highly conserved, as are the putative promoter elements recognized by these transcription factors.