Open AccessActivation of expression of the Escherichia coli cir gene by an iron-independent regulatory mechanism involving cyclic AMP-cyclic AMP receptor protein complex
Author(s) -
David W. Griggs,
K. Kafka,
C D Nau,
J Konisky
Publication year - 1990
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.172.6.3529-3533.1990
Subject(s) - biology , catabolite repression , camp receptor protein , mutant , colicin , receptor , gene , biochemistry , regulation of gene expression , gene expression , escherichia coli , microbiology and biotechnology , promoter
Synthesis of the colicin I receptor protein, encoded by the cir gene, was determined to be sensitive to control by the catabolite repression regulatory system. Under both high- and low-iron conditions for growth, mutants unable to produce cyclic AMP (cAMP) (cya) or functional cAMP receptor protein (crp) exhibited decreased membrane levels of the receptor relative to those of the wild-type strain. Exogenous addition of cAMP to the cya mutant restored maximal expression. cAMP-dependent changes in steady-state levels of cir mRNA suggested that the effect is mediated by control of transcript synthesis or stability. Potential mechanisms for regulation were examined by deletion and sequence analysis.