The mechanism of antibacterial action The peptidoglycan is composed of glycan chains of N-acetyglucosamine and N-acetylmuramic acid The biosynthesis of peptidoglycan can be considered in three stages which the last one involves the completion of the cross-link. This is accomplished by a tranpeptidation reaction, which involves transpetidase. The B-lactam antibiotics combine with and inactivate the tranpeptidaseThe mechanism of antibacterial action ◼ The peptidoglycan is composed of glycan chains of N-acetyglucosamine and N-acetylmuramic acid. ◼ The biosynthesis of peptidoglycan can be considered in three stages which the last one involves the completion of the cross-link. ◼ This is accomplished by a tranpeptidation reaction, which involves transpetidase. ◼ The ß-lactam antibiotics combine with and inactivate the tranpeptidase