title: Beta-lactamases of type culture strains of the Bacteroides fragilis group and of strains that hydrolyse cefoxitin, latamoxef and imipenem.
abstract: Susceptibilities to beta-lactam antibiotics and beta-lactamase content of two groups of Bacteroides strains were compared. Type cultures produced low levels of beta-lactamase and were susceptible to cefoxitin, latamoxef, imipenem and the combination of benzylpenicillin and clavulanic acid. Other Bacteroides strains that produced higher levels of beta-lactamase were generally less susceptible to these antibiotics; this resistance was more closely related to enzyme type than to the amount of enzyme present. The beta-lactamases produced by the test strains fell into three broad groups on the basis of antibiotic degradation and inhibitor profiles: those that inactivated benzylpenicillin, but not cefoxitin, latamoxef or imipenem, and were susceptible to inhibition by beta-lactamase inhibitors; those that hydrolysed benzylpenicillin, cefoxitin and latamoxef, but not imipenem, and which were less susceptible to inhibition by beta-lactamase inhibitors; an enzyme that inactivated all the antibiotics and was not inhibited by beta-lactamase inhibitors.
mesh_terms: D001441:Bacteroides fragilis / Q000201:enzymology*; D002440:Cefoxitin / Q000378:metabolism; D002511:Cephalosporins / Q000378:metabolism; D004352:Drug Resistance, Microbial; D015378:Imipenem; D007526:Isoelectric Point; D007700:Kinetics; D008826:Microbial Sensitivity Tests; D009070:Moxalactam / Q000378:metabolism; D009391:Nephelometry and Turbidimetry; D013845:Thienamycins / Q000378:metabolism; D065093:beta-Lactamase Inhibitors; D001618:beta-Lactamases / Q000378:metabolism*
chemical_list: D002511:Cephalosporins; D013845:Thienamycins; D065093:beta-Lactamase Inhibitors; D002440:Cefoxitin; D015378:Imipenem; D001618:beta-Lactamases; C021720:nitrocefin; D009070:Moxalactam