Molecular characterization of the PhoP-PhoQ two-component system in Escherichia coli K-12: identification of extracellular Mg2+-responsive promoters.
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ABSTRACT:
SUBMITTER: Kato A
PROVIDER: S-EPMC94065 | biostudies-literature | 1999 Sep
REPOSITORIES: biostudies-literature
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Molecular characterization of the PhoP-PhoQ two-component system in Escherichia coli K-12: identification of extracellular Mg2+-responsive promoters.
Kato A A Tanabe H H Utsumi R R
Journal of bacteriology 19990901 17
We identified Mg2+-responsive promoters of the phoPQ, mgtA, and mgrB genes of Escherichia coli K-12 by S1 nuclease analysis. Expression of these genes was induced by magnesium limitation and depended on PhoP and PhoQ. The transcription start sites were also determined, which allowed us to find a (T/G)GTTTA direct repeat in their corresponding promoter regions. ...[more]
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