Decreased Affinity of PBP3 to Methicillin in a Clinical Isolate of Staphylococcus epidermidis with Borderline Resistance to Methicillin and Free of the mecA Gene

Analysis of the antibiotic binding capacity of penicillin-binding proteins (PBPs) in a group of clinical isolates of Staphylococcus epidermidis suggests that the increased level of resistance to methicillin (MIC 4.0 μg/ml) in an isolate free of the mecA gene is due to the decreased binding capacity of PBP3.