Binding of the gene repressor BlaI to the bla operon in methicillin-resistant Staphylococcus aureus.
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 β-lactams.
Llarrull
Leticia I
LI
Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556, USA.
Prorok
Mary
M
Mobashery
Shahriar
S
D016106:Methicillin Resistance / Q000235:genetics*; D055624:Methicillin-Resistant Staphylococcus aureus; D009876:Operon / Q000502:physiology*; D013203:Staphylococcal Infections / Q000235:genetics; D047090:beta-Lactams / Q000378:metabolism
D047090:beta-Lactams