All of the following are true about Methicillin resistance in MRSA, except-: (A) Resistance is produced as a result of altered PBP's, (B) Resistance may be produced by hyperproduction of beta lactamase, (C) Resistance is primarily mediated/transmitted plasmids, (D) Resistance may be missed at incubation temperature of 370C during susceptibility testing
Answer is C. Resistance in MRSA is chromosomally mediated (not plasmid mediated). Resistance is produced as a result of altered PBP's- mediated chromosomal mec A gene which codes for altered PBP- 2A. Resistance may be produced by hyperproduction of beta-lactamase Methicillin resistance is expressed more at 30degC than at 37degC. Therefore, resistance may be missed at incubation temperature at 37degC during susceptibility testing.