β-lactam antibiotics are those antibiotic that that contain a beta-lactam ring (the cyclic amide with the nitrogen atom attached to the β-carbon) in their molecular structures. This class of antibiotics is the most commonly used and it includes penicillin derivatives, cephalosporins, monobactams, and carbapenems. The mechanism of action of β-lactam antibiotics is inhibition of cell wall biosynthesis in the bacteria.
