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H-NS-Dependent regulation of flagellar synthesis is mediated by a LysR family protein.

ABSTRACT: H-NS regulates the flagellar master operon (flhDC) and thus is necessary for flagellation of Escherichia coli. However, the molecular mechanism of its regulation has remained unknown. Genetic screening of a transposon insertion abolishing the H-NS effect revealed a previously unidentified gene, named hdfR, encoding a LysR family protein. Binding of purified HdfR to the flhDC promoter was demonstrated by a DNA mobility shift assay, indicating that HdfR is a transcriptional regulator for the flagellar master operon. Furthermore, the expression of the hdfR gene was shown to be negatively regulated by H-NS.

SUBMITTER: Ko M

PROVIDER: S-EPMC94646 | biostudies-literature | 2000 Aug

REPOSITORIES: biostudies-literature

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H-NS-Dependent regulation of flagellar synthesis is mediated by a LysR family protein.

Ko M M Park C C

Journal of bacteriology 20000801 16

H-NS regulates the flagellar master operon (flhDC) and thus is necessary for flagellation of Escherichia coli. However, the molecular mechanism of its regulation has remained unknown. Genetic screening of a transposon insertion abolishing the H-NS effect revealed a previously unidentified gene, named hdfR, encoding a LysR family protein. Binding of purified HdfR to the flhDC promoter was demonstrated by a DNA mobility shift assay, indicating that HdfR is a transcriptional regulator for the flage ...[more]

PMID: 10913108

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