Beta-lactamase is a type of enzyme responsible for bacterial resistance to beta-lactam antibiotics. Among these are penicillins, cephalosporins, carbapenems and others. They 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 antibiotic properties.
The structure of a Streptomyces β lactamase is given by PDB 1BSG EC 3.5.2.6)
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