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CtsR, a novel regulator of stress and heat shock response, controls clp and molecular chaperone gene expression in Gram‐positive bacteria
Author(s) -
Derré Isabelle,
Rapoport Georges,
Msadek Tarek
Publication year - 1999
Publication title -
molecular microbiology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.857
H-Index - 247
eISSN - 1365-2958
pISSN - 0950-382X
DOI - 10.1046/j.1365-2958.1999.01152.x
Subject(s) - biology , operon , heat shock , heat shock protein , gene , microbiology and biotechnology , repressor , genetics , atp binding cassette transporter , lactococcus lactis , derepression , bacteria , gene expression , escherichia coli , lactic acid , psychological repression , transporter
clpP and clpC of Bacillus subtilis encode subunits of the Clp ATP‐dependent protease and are required for stress survival, including growth at high temperature. They play essential roles in stationary phase adaptive responses such as the competence and sporulation developmental pathways, and belong to the so‐called class III group of heat shock genes, whose mode of regulation is unknown and whose expression is induced by heat shock or general stress conditions. The product of ctsR , the first gene of the clpC operon, has now been shown to act as a repressor of both clpP and clpC , as well as clpE , which encodes a novel member of the Hsp100 Clp ATPase family. The CtsR protein was purified and shown to bind specifically to the promoter regions of all three clp genes. Random mutagenesis, DNaseI footprinting and DNA sequence deletions and comparisons were used to define a consensus CtsR recognition sequence as a directly repeated heptad upstream from the three clp genes. This target sequence was also found upstream from clp and other heat shock genes of several Gram‐positive bacteria, including Listeria monocytogenes , Streptococcus salivarius , S. pneumoniae , S. pyogenes , S. thermophilus , Enterococcus faecalis , Staphylococcus aureus , Leuconostoc oenos , Lactobacillus sake , Lactococcus lactis and Clostridium acetobutylicum . CtsR homologues were also identified in several of these bacteria, indicating that heat shock regulation by CtsR is highly conserved in Gram‐positive bacteria.