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Regulation of beta-galactosidase expression in Bacillus megaterium DSM319 by a XylS/AraC-type transcriptional activator.

ABSTRACT: The beta-galactosidase-encoding bgaM gene of Bacillus megaterium DSM319 and the divergently orientated bgaR operon were isolated and sequenced. Both traits are subject to catabolite repression. A set of single-gene replacement mutants was generated and used to analyze gene function. BgaR was found to be a XylS/AraC-type positive transcriptional regulator of bgaM; a potential regulator binding site overlaps the bgaM promoter. A mechanism for regulation of beta-galactosidase expression in B. megaterium is proposed.

SUBMITTER: Strey J

PROVIDER: S-EPMC93790 | biostudies-literature | 1999 May

REPOSITORIES: biostudies-literature

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Regulation of beta-galactosidase expression in Bacillus megaterium DSM319 by a XylS/AraC-type transcriptional activator.

Strey J J Wittchen K D KD Meinhardt F F

Journal of bacteriology 19990501 10

The beta-galactosidase-encoding bgaM gene of Bacillus megaterium DSM319 and the divergently orientated bgaR operon were isolated and sequenced. Both traits are subject to catabolite repression. A set of single-gene replacement mutants was generated and used to analyze gene function. BgaR was found to be a XylS/AraC-type positive transcriptional regulator of bgaM; a potential regulator binding site overlaps the bgaM promoter. A mechanism for regulation of beta-galactosidase expression in B. megat ...[more]

PMID: 10322036

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