title: Inhibition of oxidative metabolism in Escherichia coli by d-camphor and restoration of oxidase activity by quinones.
abstract: Oxidative metabolism in whole cells of Escherichia coli strain 82/r was inhibited by d-camphor when glucose, pyruvate, or succinate was used as substrate. Inhibition was not due to lower surface tension in d-camphor-treated cell suspensions nor was it a function of cell permeability. Succinic, lactic, and NADH-oxidase activities were inhibited in alumina powder cell-free extracts (80 mug of protein/ml) by d-camphor (1100 mug/ml). NADH: and succinic: DCPIP oxidoreductase enzymes were unaffected by d-camphor. Menadione (vitamin K3) restored succinic, lactic, and NADH-oxidase activities in d-camphor-inhibited cell-free extracts. Concentrations of menadione used to restore succinic and NADH oxidase activities were not stimulatory in non-camphor-treated extracts. Succinic oxidase activity in d-camphor-inhibited cell-free extracts was also restored by ubiquinone (Q6) but not by vitamin K1. These results are interpreted to indicate that d-camphor may affect quinone function in E. coli.
mesh_terms: D002164:Camphor / Q000494:pharmacology*; D002474:Cell-Free System; D004926:Escherichia coli / Q000201:enzymology / Q000378:metabolism*; D005947:Glucose / Q000378:metabolism; D007770:L-Lactate Dehydrogenase / Q000378:metabolism; D009247:NADH, NADPH Oxidoreductases / Q000378:metabolism; D010088:Oxidoreductases / Q000378:metabolism*; D011773:Pyruvates / Q000378:metabolism; D011809:Quinones / Q000494:pharmacology*; D013385:Succinate Dehydrogenase / Q000378:metabolism; D013386:Succinates / Q000378:metabolism; D014451:Ubiquinone / Q000494:pharmacology; D014812:Vitamin K / Q000494:pharmacology
chemical_list: D011773:Pyruvates; D011809:Quinones; D013386:Succinates; D014812:Vitamin K; D014451:Ubiquinone; D002164:Camphor; D010088:Oxidoreductases; D007770:L-Lactate Dehydrogenase; D013385:Succinate Dehydrogenase; D009247:NADH, NADPH Oxidoreductases; D005947:Glucose