title: Pyruvate dehydrogenase activity and metronidazole susceptibility in Bacteroides fragilis.
abstract: Pyruvate dehydrogenase activity was present and comparable (giving a colour change of 202-673 od units/min/g protein in our assay system) in two clinical strains of Bacteroides fragilis exhibiting reduced sensitivity to metronidazole (MIC 2-8 mg/l at 48 h) in a resistant strain (Ingham's) of Bact. fragilis (MIC 64/mg/l) and in two sensitive strains of Bact. fragilis (MIC 0.5 mg/l). Pyruvate dehydrogenase activity was not detected in a capnocytophaga strain (sensitive to 50 micrograms disc of metronidazole), in Escherichia coli or in 'Bact. fragilis' strain (Britz) AM24s (MIC greater than 64 mg/l). Further testing of AM24s strain indicated that it was not Bact. fragilis but a facultatively anaerobic Gram-negative rod. Pyruvate dehydrogenase activity therefore, is similar in sensitive and resistant strains of Bact. fragilis and is unlikely to be related to the mechanism of resistance to metronidazole.
mesh_terms: D001441:Bacteroides fragilis / Q000187:drug effects / Q000201:enzymology*; D008795:Metronidazole / Q000494:pharmacology*; D008826:Microbial Sensitivity Tests; D010100:Oxygen / Q000494:pharmacology; D011768:Pyruvate Dehydrogenase Complex / Q000032:analysis*
chemical_list: D011768:Pyruvate Dehydrogenase Complex; D008795:Metronidazole; D010100:Oxygen