Molecular Classification

The molecular classification of Beta-lactamases is based on the nucleotide and amino acid sequences in these enzymes. To date, four classes are recognised (A-D), correlating with the functional classification. Classes A, C, and D act by a serine-based mechanism, whereas class B or metallo-Beta-lactamases need zinc for their action "Penicillinase" was discovered in 1940 and re-named Beta-lactamase when the structure of the Beta-lactam ring was finally elucidated.