title: Origin and function of penicillinase: a problem in biochemical evolution.
mesh_terms: D000222:Adaptation, Physiological; D001409:Bacillus cereus / Q000201:enzymology; D001419:Bacteria / Q000201:enzymology*; D005075:Biological Evolution; D002511:Cephalosporins / Q000502:physiology; D004926:Escherichia coli / Q000201:enzymology; D006801:Humans; D007709:Klebsiella / Q000201:enzymology; D010405:Penicillinase / Q000096:biosynthesis* / Q000494:pharmacology* / Q000502:physiology*; D013210:Staphylococcus / Q000201:enzymology
chemical_list: D002511:Cephalosporins; D010405:Penicillinase