confers_resistance_to_drug_class cephalosporin confers_resistance_to_drug_class penicillin beta-lactam class C beta-lactamase ampC-type beta-lactamase AmpC beta-lactamases are clinically important class C beta-lactamase enzymes which confer resistance to cephalosporins and penicillin-like antibiotics. AmpC beta-lactamases are typically found in Enterobacteriaceae, and were described in Escherichia coli in 1940 as the first reported enzymatic deactivation of penicillin. The name AmpC connects these enzymes functionally across many species, however these enzymes are generally unnamed and not phylogenetically related. antibiotic_resistance ARO:3004232