Beta-lactamases are bacterial enzymes that hydrolyze the beta-lactam ring of penicillins, cephalosporins, and carbapenems, rendering them inactive. They are the most common mechanism of antibiotic resistance and a central concern in the antimicrobial resistance crisis. Extended-spectrum beta-lactamases (ESBLs) and carbapenemases (KPC, NDM, OXA-48) confer resistance to last-resort antibiotics.
Co-Selection with Metal Resistance
Beta-lactamase genes frequently co-locate with metal resistance genes on the same plasmids and mobile genetic elements — meaning environmental metal exposure selects for beta-lactamase-producing bacteria without antibiotic exposure [1] [2]. This is documented in CKD gut microbiome [3].
WikiBiome Relevance
The beta-lactamase → co selection → metal resistance connection is a core WikiBiome insight: heavy metal pollution in agriculture, water, and food is an unrecognized driver of antibiotic resistance in the human gut microbiome.
Cross-References
- antimicrobial resistance — AMR context
- co selection — metal-antibiotic co-resistance on shared plasmids
- cephalosporin — beta-lactam antibiotic class
- vancomycin — alternative when beta-lactams fail
- klebsiella — major carbapenemase-producing genus