Functional roles for the GerE-family carboxyl-terminal domains of nitrate response regulators NarL and NarP of Escherichia coli K-12.

ABSTRACT: NarL and NarP are paralogous response regulators that control anaerobic gene expression in response to the favoured electron acceptors nitrate and nitrite. Their DNA-binding carboxyl termini are in the widespread GerE-LuxR-FixJ subfamily of tetrahelical helix-turn-helix domains. Previous biochemical and crystallographic studies with NarL suggest that dimerization and DNA binding by the carboxyl-terminal domain (CTD) is inhibited by the unphosphorylated amino-terminal receiver domain. We report here that NarL-CTD and NarP-CTD, liberated from their receiver domains, activated transcription in vivo from the class II napF and yeaR operon control regions, but failed to activate from the class I narG and fdnG operon control regions. Alanine substitutions were made to examine requirements for res

SUBMITTER: Lin AV 

PROVIDER: S-EPMC3068693 | biostudies-literature | 2010 Oct

REPOSITORIES: biostudies-literature