Site-directed mutagenesis identifies a molecular switch involved in copper sensing by the histidine kinase CinS in Pseudomonas putida KT2440.
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ABSTRACT:
SUBMITTER: Quaranta D
PROVIDER: S-EPMC2725577 | biostudies-literature | 2009 Aug
REPOSITORIES: biostudies-literature
Publications
Site-directed mutagenesis identifies a molecular switch involved in copper sensing by the histidine kinase CinS in Pseudomonas putida KT2440.
Quaranta Davide D McEvoy Megan M MM Rensing Christopher C
Journal of bacteriology 20090619 16
In the presence of copper, Pseudomonas putida activates transcription of cinAQ via the two-component system CinS-CinR. The CinS-CinR TCS was responsive to 0.5 microM copper and was specifically activated only by copper and silver. Modeling studies of CinS identified a potential copper binding site containing H37 and H147. CinS mutants with H37R and H147R mutations had an almost 10-fold reduced copper-dependent induction of cinAQ compared to the wild type. ...[more]
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