A conserved structural module regulates transcriptional responses to diverse stress signals in bacteria.
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ABSTRACT:
SUBMITTER: Campbell EA
PROVIDER: S-EPMC2390684 | biostudies-literature | 2007 Sep
REPOSITORIES: biostudies-literature
Publications
A conserved structural module regulates transcriptional responses to diverse stress signals in bacteria.
Campbell Elizabeth A EA Greenwell Roger R Anthony Jennifer R JR Wang Sheng S Lim Lionel L Das Kalyan K Sofia Heidi J HJ Donohue Timothy J TJ Darst Seth A SA
Molecular cell 20070901 5
A transcriptional response to singlet oxygen in Rhodobacter sphaeroides is controlled by the group IV sigma factor sigma(E) and its cognate anti-sigma ChrR. Crystal structures of the sigma(E)/ChrR complex reveal a modular, two-domain architecture for ChrR. The ChrR N-terminal anti-sigma domain (ASD) binds a Zn(2+) ion, contacts sigma(E), and is sufficient to inhibit sigma(E)-dependent transcription. The ChrR C-terminal domain adopts a cupin fold, can coordinate an additional Zn(2+), and is requi ...[more]
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