Biomaterial Database

[Rotenone-insensitive NADH oxydation in mitochondrial suspension occurs by NADH dehydrogenase of respiratory chain fragments]. 2004

I V Sharova, and N L Vekshin

Two types of NADH oxidation, rotenone-sensitive and rotenone-insensitive, in suspension of beef heart mitochondria were investigated by the spectrophotometric method. The oxidation of the added NADH by mitochondria in hypotonic media occurs only through the NADH dehydrogenase of the respiratory chain, since it was totally blocked by rotenone or amytal (and also by antimycin A or azide), but the ferricyanide-activated NADH oxidation was insensitive to these inhibitors. The insensitivity of the NADH dehydrogenase to rotenone appears to be due to a shunt of the electron transfer to ferricyanide without involving of ubiquinone. Both types of the oxydation occur through one and the same enzyme, which exists in two states. The evidence in favour of this is that NAD+ and DTT slightly influence the first type of oxidation but strongly inhibit the second one. The ferricyanide-activated NADH oxidation takes place in NADH dehydrogenase fragments released from mitochondria. Low Ds-Na concentrations block the respiratory chain NADH oxidation but increase the velocity of the ferricyanide-dependent oxidation. Probably, the increase is the result of the detergent-induced additional releasing of the fragments. The express-method for the preparation of the initially purified fraction with a high yield of detergent-containing fragments of the active enzyme is described.

UI	MeSH Term	Description	Entries
D007038	Hypotonic Solutions	Solutions that have a lesser osmotic pressure than a reference solution such as blood, plasma, or interstitial fluid.	Solutions, Hypotonic
D008929	Mitochondria, Heart	The mitochondria of the myocardium.	Heart Mitochondria,Myocardial Mitochondria,Mitochondrion, Heart,Heart Mitochondrion,Mitochondria, Myocardial
D009243	NAD	A coenzyme composed of ribosylnicotinamide 5'-diphosphate coupled to adenosine 5'-phosphate by pyrophosphate linkage. It is found widely in nature and is involved in numerous enzymatic reactions in which it serves as an electron carrier by being alternately oxidized (NAD+) and reduced (NADH). (Dorland, 27th ed)	Coenzyme I,DPN,Diphosphopyridine Nucleotide,Nadide,Nicotinamide-Adenine Dinucleotide,Dihydronicotinamide Adenine Dinucleotide,NADH,Adenine Dinucleotide, Dihydronicotinamide,Dinucleotide, Dihydronicotinamide Adenine,Dinucleotide, Nicotinamide-Adenine,Nicotinamide Adenine Dinucleotide,Nucleotide, Diphosphopyridine
D009245	NADH Dehydrogenase	A flavoprotein and iron sulfur-containing oxidoreductase that catalyzes the oxidation of NADH to NAD. In eukaryotes the enzyme can be found as a component of mitochondrial electron transport complex I. Under experimental conditions the enzyme can use CYTOCHROME C GROUP as the reducing cofactor. The enzyme was formerly listed as EC 1.6.2.1.	NADH Cytochrome c Reductase,Diaphorase (NADH Dehydrogenase),NADH (Acceptor) Oxidoreductase,NADH Cytochrome c Oxidoreductase,Dehydrogenase, NADH
D010084	Oxidation-Reduction	A chemical reaction in which an electron is transferred from one molecule to another. The electron-donating molecule is the reducing agent or reductant; the electron-accepting molecule is the oxidizing agent or oxidant. Reducing and oxidizing agents function as conjugate reductant-oxidant pairs or redox pairs (Lehninger, Principles of Biochemistry, 1982, p471).	Redox,Oxidation Reduction
D002417	Cattle	Domesticated bovine animals of the genus Bos, usually kept on a farm or ranch and used for the production of meat or dairy products or for heavy labor.	Beef Cow,Bos grunniens,Bos indicus,Bos indicus Cattle,Bos taurus,Cow,Cow, Domestic,Dairy Cow,Holstein Cow,Indicine Cattle,Taurine Cattle,Taurus Cattle,Yak,Zebu,Beef Cows,Bos indicus Cattles,Cattle, Bos indicus,Cattle, Indicine,Cattle, Taurine,Cattle, Taurus,Cattles, Bos indicus,Cattles, Indicine,Cattles, Taurine,Cattles, Taurus,Cow, Beef,Cow, Dairy,Cow, Holstein,Cows,Dairy Cows,Domestic Cow,Domestic Cows,Indicine Cattles,Taurine Cattles,Taurus Cattles,Yaks,Zebus
D004579	Electron Transport	The process by which ELECTRONS are transported from a reduced substrate to molecular OXYGEN. (From Bennington, Saunders Dictionary and Encyclopedia of Laboratory Medicine and Technology, 1984, p270)	Respiratory Chain,Chain, Respiratory,Chains, Respiratory,Respiratory Chains,Transport, Electron
D005292	Ferricyanides	Inorganic salts of the hypothetical acid, H3Fe(CN)6.
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D012402	Rotenone	A botanical insecticide that is an inhibitor of mitochondrial electron transport.