Inhibition of energy-dependent transhydrogenase reaction by N-)phosphonomethyl) glycine in isolated rat liver mitochondria.
The pattern of interaction of various concentrations of N-phosphonomethyl derivative of glycine (PMG) with membrane-bound nicotinamide nucleotide transhydrogenase has been investigated in intact mitochondria isolated from rat liver. Lower concentrations of PMG ( less than 1.50 . 10(-4)M) had no significant effect (12% inhibition) on the activity of the enzyme when the reaction was supported by energy generated from succinate oxidation. Inhibition increased as the concentration of the herbicide was raised: at 3.12 . 10(-4) the degree was 28% and at 1.25 . 10(-3)M PMG, 46% (maximal inhibition). Similar results were obtained when ATP was used as the source of energy. These observations indicate that like thyroxine, an uncoupler of oxidative phosphorylation, PMG interacts with both oxidative phosphorylation and energy-dependent transhydrogenase reaction.
D000818:Animals; D004734:Energy Metabolism / Q000187:drug effects; D005998:Glycine / Q000031:analogs & derivatives* / Q000633:toxicity; D006540:Herbicides / Q000633:toxicity*; D066298:In Vitro Techniques; D008930:Mitochondria, Liver / Q000187:drug effects* / Q000201:enzymology; D009247:NADH, NADPH Oxidoreductases / Q000037:antagonists & inhibitors*; D009250:NADP Transhydrogenases / Q000037:antagonists & inhibitors*; D051381:Rats; D014475:Uncoupling Agents / Q000633:toxicity*; D000097797:Glyphosate
D005998:Glycine; D006540:Herbicides; D009247:NADH, NADPH Oxidoreductases; D009250:NADP Transhydrogenases; D014475:Uncoupling Agents; D000097797:Glyphosate