title: Tetracyano-2,2-bipyridineiron(iii), an improved electron acceptor for the spectrophotometric assay of beta-oxidation and of succinate dehydrogenase in intact mitochondria.
abstract: A recently described direct reading assay for beta-oxidation and for succinate oxidation in intact mitochondria using [Fe(CN)6]3- as final electron acceptor [Osmundsen & Bremer (1977) Biochem. J. 164. 621--633] has been improved by using instead tetracyano-2,2-bipyridineiron(III) [Fe(CN)4(bpy)]-, which gives a 2.6 times greater absorbance change on reduction. Some physical and kinetic properties of [Fe(CN)4(bpy)]- are described. The use of exogenous cytochrome c(III) as electron acceptor was also tested; this gives the largest absorbance change, although the absolute rate of reaction is only approx. one-third of that using [Fe(CN)6]3- or [Fe(CN)4(bpy)]-.
mesh_terms: D000818:Animals; D003574:Cytochrome c Group / Q000378:metabolism; D004579:Electron Transport; D005292:Ferricyanides / Q000378:metabolism*; D006801:Humans; D066298:In Vitro Techniques; D007700:Kinetics; D008297:Male; D008928:Mitochondria / Q000201:enzymology; D008930:Mitochondria, Liver / Q000201:enzymology*; D010084:Oxidation-Reduction; D051381:Rats; D011919:Rats, Inbred Strains; D013053:Spectrophotometry / Q000379:methods*; D013385:Succinate Dehydrogenase / Q000378:metabolism*
chemical_list: D003574:Cytochrome c Group; D005292:Ferricyanides; C036081:tetracyano-2,2-bipyridine iron (III); C017165:cytochrome c(3); D013385:Succinate Dehydrogenase; C028033:potassium ferricyanide