β-Lactam antibiotics with susceptible β-lactam rings (β-lactams)

β-Lactam antibiotics with susceptible β-lactam rings are a broad and clinically vital class of antibacterial agents characterized by a four-membered lactam ring [1, 3]. This class includes penicillins, cephalosporins, carbapenems, and monobactams, which are primarily used to treat a wide range of bacterial infections [1, 4]. Their biological function is to inhibit bacterial cell wall synthesis by acting as structural analogs of the D-alanyl-D-alanine terminus of peptidoglycan precursors [1, 5]. They covalently bind to the active site of penicillin-binding proteins (PBPs), thereby blocking the transpeptidation reaction required for peptidoglycan cross-linking and leading to bacterial cell lysis [3, 5]. The 'susceptible' designation refers to the chemical vulnerability of the β-lactam ring to hydrolysis by bacterial β-lactamase enzymes, which is a major mechanism of antibiotic resistance [2]. To overcome this, these antibiotics are frequently co-administered with β-lactamase inhibitors like clavulanic acid or tazobactam, which protect the antibiotic from enzymatic degradation [2, 3].

Other names

Beta-lactam antibioticsPenicillinsCephalosporinsCarbapenemsMonobactamsSusceptible beta-lactams

These molecules inhibit bacterial cell wall synthesis by covalently binding to penicillin-binding proteins (PBPs), which are enzymes responsible for the final transpeptidation step of peptidoglycan cross-linking [1, 3].