β-lactamases

Definition

β-lactamases are enzymes produced by bacteria that hydrolyze the β-lactam ring of β-lactam antibiotics, rendering them ineffective. They are a major mechanism of bacterial resistance to these drugs.

5 Must Know Facts For Your Next Test

1. β-lactamases break down antibiotics such as penicillins and cephalosporins.
2. Extended-spectrum β-lactamases (ESBLs) can hydrolyze a wide range of β-lactam antibiotics, including third-generation cephalosporins.
3. The presence of β-lactamase genes can be detected through molecular techniques like PCR.
4. Inhibitors like clavulanic acid are often used in conjunction with β-lactam antibiotics to counteract the effect of β-lactamases.
5. Bacteria producing carbapenemases, a type of β-lactamase, show resistance to carbapenem antibiotics, which are usually last-resort drugs.

Review Questions

• What type of antibiotics do β-lactamases target and hydrolyze?
• How do extended-spectrum β-lactamases (ESBLs) differ from regular β-lactamases?
• What is one method used to detect the presence of β-lactamase genes in bacteria?

Related terms

Antimicrobial Resistance:

The ability of microbes to resist the effects of drugs that once killed them.

Carbapenemase: A type of enzyme produced by certain bacteria that breaks down carbapenems and leads to antibiotic resistance.

Clavulanic Acid: A compound used alongside β-lactam antibiotics to inhibit the action of β-lactamases.