Dissection of Events in the Resistance to beta-Lactam Antibiotics Mediated by the Protein BlaR1 from Staphylococcus aureus.

LLARRULL, L.I.; MOBASHERY, S.

BIOCHEMISTRY

AMER CHEMICAL SOC

Lugar: Washington; Año: 2012 vol. 51 p. 4642 - 4649

0006-2960

A heterologous expression system was used to evaluate activation of BlaR1, a sensor/signal transducer protein of Staphylococcus aureus with a central role in resistance to beta-lactam antibiotics. In the absence of other S. aureus proteins that might respond to antibiotics and participate in signal transduction events, we documented that BlaR1 fragmentation is autolytic, that it occurs in the absence of antibiotics, and that BlaR1 directly degrades BlaI, the gene repressor of the system. Furthermore, we disclosed that this proteolytic activity is metal ion-dependent and that it is not modulated directly by acylation of the sensor domain by beta-lactam antibiotics.