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An lrp-like gene of Bacillus subtilis involved in branched-chain amino acid transport.

ABSTRACT: The azlB locus of Bacillus subtilis was defined previously by a mutation conferring resistance to a leucine analog, 4-azaleucine (J. B. Ward, Jr., and S. A. Zahler, J. Bacteriol. 116:727-735, 1973). In this report, azlB is shown to be the first gene of an operon apparently involved in branched-chain amino acid transport. The product of the azlB gene is an Lrp-like protein that negatively regulates expression of the azlBCDEF operon. Resistance to 4-azaleucine in azlB mutants is due to overproduction of AzlC and AzlD, two novel hydrophobic proteins.

SUBMITTER: Belitsky BR

PROVIDER: S-EPMC179416 | biostudies-other | 1997 Sep

REPOSITORIES: biostudies-other

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An lrp-like gene of Bacillus subtilis involved in branched-chain amino acid transport.

Belitsky B R BR Gustafsson M C MC Sonenshein A L AL Von Wachenfeldt C C

Journal of bacteriology 19970901 17

The azlB locus of Bacillus subtilis was defined previously by a mutation conferring resistance to a leucine analog, 4-azaleucine (J. B. Ward, Jr., and S. A. Zahler, J. Bacteriol. 116:727-735, 1973). In this report, azlB is shown to be the first gene of an operon apparently involved in branched-chain amino acid transport. The product of the azlB gene is an Lrp-like protein that negatively regulates expression of the azlBCDEF operon. Resistance to 4-azaleucine in azlB mutants is due to overproduct ...[more]

PMID: 9287000

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