title: Beta-lactamase alteration of beta-lactam inhibitory zones.
abstract: A disk approximation test, in which the inhibitory zone of one beta-lactam antibiotic is truncated under influence of another beta-lactam (e.g. cefoxitin), was used as a screen for the presence of inducible beta-lactamase. By using beta-lactamase extracts and a specific inhibitor, it was shown that chromosomal beta-lactamase can indeed be the sole cause of truncated beta-lactam inhibitory zones.
mesh_terms: D000900:Anti-Bacterial Agents / Q000037:antagonists & inhibitors* / Q000378:metabolism; D004926:Escherichia coli / Q000187:drug effects*; D008826:Microbial Sensitivity Tests; D011550:Pseudomonas aeruginosa / Q000187:drug effects* / Q000201:enzymology; D001618:beta-Lactamases / Q000378:metabolism*; D047090:beta-Lactams
chemical_list: D000900:Anti-Bacterial Agents; D047090:beta-Lactams; D001618:beta-Lactamases