the penicillinases produced by staphylococcus aureus , the plasmid-mediated beta-lactamases such as the tem-type , the chromosomally-mediated penicillinases from klebsiella pneumoniae and other closely-related beta-lactamases , and a few chromosomally-mediated cephalosporinases , such as that produced by proteus vulgaris , are powerfully inhibited by clavulanic acid .
C0597979
beta-lactamases
C0728805
cephalosporinases