Beta-lactamases are enzymes produced by some bacteria and are
responsible for their resistance to beta-lactam antibiotics like
penicillins, cephamycins, and carbapenems (ertapenem)
(Cephalosporins are relatively resistant to beta-lactamase).
These antibiotics have a common element in their molecular
structure: a four-atom ring known as a beta-lactam. The lactamase
enzyme breaks that ring open, deactivating the molecule's