Sensitivity to NN'-dicyclohexylcarbodi-imide of proton translocation by mitochondrial NADH:ubiquinone oxidoreductase.
Proton extrusion during ferricyanide reduction by NADH-generating substrates or succinate was studied in isolated rat liver mitochondria with the use of optical indicators. NN'-Dicyclohexylcarbodi-imide (DCCD) caused a decrease of 84% in the H+/e- ratio of NADH:cytochrome c reduction, but a decrease of only 49% in that of succinate:cytochrome c reduction, even though electron transfer was decreased equally in both spans. The data indicate that a DCCD-sensitive channel operates in the NADH:ubiquinone oxidoreductase region of the respiratory chain.
D000818:Animals; D002234:Carbodiimides / Q000494:pharmacology*; D004024:Dicyclohexylcarbodiimide / Q000494:pharmacology*; D005292:Ferricyanides / Q000494:pharmacology; D008297:Male; D008930:Mitochondria, Liver / Q000187:drug effects / Q000201:enzymology*; D016660:NAD(P)H Dehydrogenase (Quinone); D010084:Oxidation-Reduction; D011522:Protons; D011808:Quinone Reductases / Q000378:metabolism*; D051381:Rats; D011919:Rats, Inbred Strains; D013386:Succinates / Q000378:metabolism; D019802:Succinic Acid
D002234:Carbodiimides; D005292:Ferricyanides; D011522:Protons; D013386:Succinates; D004024:Dicyclohexylcarbodiimide; D019802:Succinic Acid; D016660:NAD(P)H Dehydrogenase (Quinone); D011808:Quinone Reductases