Biomaterial Database

The molecular morphology of bovine heart mitochondrial NADH----ubiquinone reductase. Native disulfide-linked subunits and rotenone-induced conformational changes. 1985

J A Gondal, and W M Anderson

Bovine heart mitochondrial NADH----ubiquinone reductase (complex I), contains two disulfide-linked subunits of 75 and 33 kDa as revealed by two-dimensional sodium dodecyl sulfate-polyacrylamide gel electrophoresis with beta-mercaptoethanol omitted from preparation of the sample for the first dimension. Two unidentified polypeptides (110-115 and 69 kDa) are also found in disulfide linkage with the two complex I subunits. The 110-115-kDa polypeptide appears to be pyridine dinucleotide transhydrogenase by several criteria including selective precipitation with an antibody raised to the purified transhydrogenase. The two disulfide-linked subunits were also found in a product cross-linked for 2 min with dithiobis (succinimidyl propionate) (DSP) along with five other complex I subunits of 53-57, 42, 24-27, 17-18, and 12.5-15.5 kDa (Gondal, J.A., and Anderson, W.M. (1985) J. Biol. Chem. 260, 5931-5935) indicating that these seven subunits lie within 11-12 A of each other at one or more points in space in the enzyme's interior. Cross-linking of complex I with DSP for 2 min in the presence of 1 microM rotenone yielded a cross-linked product consisting of the two natural disulfide-linked subunits and the 110-115- and 69-kDa polypeptides. This suggests that rotenone induces a conformational change in the enzyme that moves the seven DSP cross-linked subunits away from each other and outside the 11-12 A bridging distance of DSP. This alteration in conformation may be communicated to iron-sulfur center N-2 within the hydrophobic outer shell of the enzyme to prevent electron transfer to its natural electron acceptor, ubiquinone. A model of rotenone action based upon these observations is presented.

UI	MeSH Term	Description	Entries
D008623	Mercaptoethanol	A water-soluble thiol derived from hydrogen sulfide and ethanol. It is used as a reducing agent for disulfide bonds and to protect sulfhydryl groups from oxidation.	2-ME,2-Mercaptoethanol,2 Mercaptoethanol
D008929	Mitochondria, Heart	The mitochondria of the myocardium.	Heart Mitochondria,Myocardial Mitochondria,Mitochondrion, Heart,Heart Mitochondrion,Mitochondria, Myocardial
D011487	Protein Conformation	The characteristic 3-dimensional shape of a protein, including the secondary, supersecondary (motifs), tertiary (domains) and quaternary structure of the peptide chain. PROTEIN STRUCTURE, QUATERNARY describes the conformation assumed by multimeric proteins (aggregates of more than one polypeptide chain).	Conformation, Protein,Conformations, Protein,Protein Conformations
D011808	Quinone Reductases	NAD(P)H:(quinone acceptor) oxidoreductases. A family that includes three enzymes which are distinguished by their sensitivity to various inhibitors. EC 1.6.99.2 (NAD(P)H DEHYDROGENASE (QUINONE);) is a flavoprotein which reduces various quinones in the presence of NADH or NADPH and is inhibited by dicoumarol. EC 1.6.99.5 (NADH dehydrogenase (quinone)) requires NADH, is inhibited by AMP and 2,4-dinitrophenol but not by dicoumarol or folic acid derivatives. EC 1.6.99.6 (NADPH dehydrogenase (quinone)) requires NADPH and is inhibited by dicoumarol and folic acid derivatives but not by 2,4-dinitrophenol.	Menaquinone Reductases,Reductases, Menaquinone,Reductases, Quinone
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
D002627	Chemistry, Physical	The study of CHEMICAL PHENOMENA and processes in terms of the underlying PHYSICAL PHENOMENA and processes.	Physical Chemistry,Chemistries, Physical,Physical Chemistries
D003432	Cross-Linking Reagents	Reagents with two reactive groups, usually at opposite ends of the molecule, that are capable of reacting with and thereby forming bridges between side chains of amino acids in proteins; the locations of naturally reactive areas within proteins can thereby be identified; may also be used for other macromolecules, like glycoproteins, nucleic acids, or other.	Bifunctional Reagent,Bifunctional Reagents,Cross Linking Reagent,Crosslinking Reagent,Cross Linking Reagents,Crosslinking Reagents,Linking Reagent, Cross,Linking Reagents, Cross,Reagent, Bifunctional,Reagent, Cross Linking,Reagent, Crosslinking,Reagents, Bifunctional,Reagents, Cross Linking,Reagents, Cross-Linking,Reagents, Crosslinking
D004220	Disulfides	Chemical groups containing the covalent disulfide bonds -S-S-. The sulfur atoms can be bound to inorganic or organic moieties.	Disulfide
D004591	Electrophoresis, Polyacrylamide Gel	Electrophoresis in which a polyacrylamide gel is used as the diffusion medium.	Polyacrylamide Gel Electrophoresis,SDS-PAGE,Sodium Dodecyl Sulfate-PAGE,Gel Electrophoresis, Polyacrylamide,SDS PAGE,Sodium Dodecyl Sulfate PAGE,Sodium Dodecyl Sulfate-PAGEs
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