β-lactam ring

Definition

A β-lactam ring is a four-membered lactam (a cyclic amide) that forms the core structure of several antibiotic classes, including penicillins and cephalosporins. Its presence is critical for the antibacterial activity of these antibiotics by inhibiting cell wall synthesis.

5 Must Know Facts For Your Next Test

1. The β-lactam ring targets and inhibits penicillin-binding proteins (PBPs) involved in bacterial cell wall synthesis.
2. β-lactam antibiotics are commonly used against Gram-positive bacteria due to their thick peptidoglycan layer.
3. Resistance to β-lactam antibiotics can occur through the production of β-lactamase enzymes by bacteria, which hydrolyze the β-lactam ring.
4. Modifications to the β-lactam ring can result in different classes of antibiotics with varied spectrums of activity, such as carbapenems and monobactams.
5. Combination therapies using β-lactamase inhibitors (e.g., clavulanic acid) help counter bacterial resistance to β-lactam antibiotics.

Review Questions

Related terms

Penicillin:

A class of antibiotics that contain a β-lactam ring and target bacterial cell wall synthesis.

Cephalosporin: Another class of β-lactam antibiotics that are frequently used to treat a variety of infections.

β-Lactamase: An enzyme produced by certain bacteria that deactivates β-lactam antibiotics by breaking open the β-lactam ring.