No relationship exists between PBP 2a amounts expressed in different MRSA strains obtained clinically and their beta-lactam MIC values.

After establishing a linear relationship between the amount of penicillin-binding protein (PBP) 2a and membrane proteins of methicillin-resistant Staphylococcus aureus (MRSA) COL by dot-blot analysis using an antibody against PBP 2a, we determined the PBP 2a quantities in membrane fractions prepared from 14 different MRSA cells. Methicillin-sensitive S. aureus ATCC 6538P was used as a quality control strain. The amounts of PBP 2a diverged among the strains, and no relationship to beta-lactam MIC values were observed in the corresponding strains.