We disclose herein that the BlaR1 protein of methicillin-resistant Staphylococcus aureus (MRSA), an antibiotic sensor/signal transducer, is phosphorylated on exposure to β-lactam antibiotics. This event is critical for the onset of the biochemical events that unleash induction of antibiotic resistance. The BlaR1 phosphorylation and the antibiotic-resistance phenotype are abrogated in the presence of inhibitors described herein that restore susceptibility of the organism to β-lactam antibiotics. The invention thus provides compounds and methods for abrogating antibiotic resistance to β-lactam antibiotics and for treating infections causes by antibiotics prone to developing resistance.
