title: Beta-lactamases in hospital strains of gram-negative bacteria.
abstract: A collection of 98 strains of enteric Gramnegative bacteria isolated in routine investigations in a hospital laboratory all showed beta-lactamase activity, and 39 of them (40%) produced sufficient enzyme to allow determination of their relative activities against benzylpenicillin, ampicillin and cephaloridine (substrate profiles). The commonest type of beta-lactamase, detected in 33 of the 39 strains, was an "all-purpose" enzyme that showed similar activity against the penicillins and the cephalosporins. All 39 were resistant to multiple antibiotics. They were examined for their ability to transfer the beta-lactamase gene during R-factor transfer, and transferability of the beta-lactamase gene was demonstrated in 13 strains out of 32.
mesh_terms: D000581:Amidohydrolases / Q000378:metabolism*; D000667:Ampicillin / Q000494:pharmacology; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D002509:Cephaloridine / Q000494:pharmacology; D002701:Chloramphenicol / Q000494:pharmacology; D002729:Chloromercuribenzoates / Q000494:pharmacology; D003023:Cloxacillin / Q000494:pharmacology; D003428:Cross Infection / Q000382:microbiology*; D004755:Enterobacteriaceae / Q000187:drug effects / Q000201:enzymology*; D006801:Humans; D010400:Penicillin G / Q000494:pharmacology; D010403:Penicillin Resistance; D011815:R Factors; D013752:Tetracycline / Q000494:pharmacology
chemical_list: D000900:Anti-Bacterial Agents; D002729:Chloromercuribenzoates; D002701:Chloramphenicol; D000667:Ampicillin; D000581:Amidohydrolases; D013752:Tetracycline; D002509:Cephaloridine; D003023:Cloxacillin; D010400:Penicillin G