What is beta-lactamase?

Answer 1

Beta lactamase is an enzyme, which is produced by some bacteria. This enzyme brakes the beta lactum ring that is present in beta lactum antibiotics. You have four groups in beta-lactum antibiotics. They are penicillins, cephalosporins, monobactums and carbapenems. So you naturally have the enzymes penicillinase, cephalospoinase, monobactamase and carbapenamase. Whether they are one and the same enzyme or four different enzymes is not clear to the contributor and needs comment by expert in this field.

Answer 2

A beta-lactam is a lactam with a four-membered ring structure - a structural element of many antibiotics, including penicillin.