Activation of BlaR1 protein of methicillin-resistant Staphylococcus aureus, its proteolytic processing, and recovery from induction of resistance.

ABSTRACT: The fates of BlaI, the gene repressor protein for the bla operon, BlaR1, the β-lactam sensor/signal transducer, and PC1 β-lactamase in four strains of Staphylococcus aureus upon exposure to four different β-lactam antibiotics were investigated as a function of time. The genes for the three proteins are encoded by the bla operon, the functions of which afford inducible resistance to β-lactam antibiotics in S. aureus. BlaR1 protein is expressed at low copy number. Acylation of the sensor domain of BlaR1 by β-lactam antibiotics initiates signal transduction to the cytoplasmic domain, a zinc protease, which is activated and degrades BlaI. This proteolytic degradation derepresses transcription of all three genes, resulting in inducible resistance. These processes take place within minutes of ex

SUBMITTER: Llarrull LI 

PROVIDER: S-EPMC3207446 | biostudies-literature | 2011 Nov

REPOSITORIES: biostudies-literature