Overall conclusions. We have demonstrated P2As as a class of penicillin G enhancers that function through blaZ suppression, resulting in reduced penicillinase expression. This is an alternate implementation of Moreillon's strategy, switching direct penicillinase inhibitors like clavulanate and sulbactam with a P2A as a blaZ suppressor. This is a conceptual innovation. It is critical to note that P2As are already able to reduce the MIC of penicillin G to ≤32 μg/mL. This is at maximum 4-8-fold above the point where PBP2a is unable to prevent penicillins from sterilizing foci of infection (MIC 8 μg/mL). The MIC of the MRSA strain used in those experiments was similar to our chosen MRSA (≥128 μg/mL vs. 256 μg/mL), so the results are directly comparable.