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Binding of the gene repressor BlaI to the bla operon in methicillin-resistant Staphylococcus aureus.

ABSTRACT: The expression of the gene products in many methicillin-resistant Staphylococcus aureus (MRSA) strains is regulated by the gene repressor BlaI. Here we show that BlaI is a mixture of monomer and dimer at in vivo concentrations, binds to the operator regions preferentially as a monomeric protein, and the measured dissociation constants and in vivo concentrations account for the basal level transcription of the resistance genes. These observations for the first time provide a quantitative picture of the processes that take place in the cytoplasm that lead to the induction of antibiotic resistance factors to counter the challenge by ?-lactams.

SUBMITTER: Llarrull LI

PROVIDER: S-EPMC2942778 | biostudies-literature | 2010 Sep

REPOSITORIES: biostudies-literature

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Binding of the gene repressor BlaI to the bla operon in methicillin-resistant Staphylococcus aureus.

Llarrull Leticia I LI Prorok Mary M Mobashery Shahriar S

Biochemistry 20100901 37

The expression of the gene products in many methicillin-resistant Staphylococcus aureus (MRSA) strains is regulated by the gene repressor BlaI. Here we show that BlaI is a mixture of monomer and dimer at in vivo concentrations, binds to the operator regions preferentially as a monomeric protein, and the measured dissociation constants and in vivo concentrations account for the basal level transcription of the resistance genes. These observations for the first time provide a quantitative picture ...[more]

PMID: 20722402

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