title: The subunit structure of bovine heart mitochondrial transhydrogenase.
abstract: Reaction of purified bovine heart transhydrogenase with bifunctional cross-linking reagents dimethyl adipimidate, dimethyl pimelimidate, dimethyl suberimidate, and dithiobis(succinimidyl propionate) results in the appearance of a dimer band on sodium dodecyl sulfate polyacrylamide gels with no higher oligomers formed. Treatment of the enzyme with 6 M urea led to inactivation and prevented cross-linking by dimethyl suberimidate. Transhydrogenase reconstituted into phosphatidylcholine proteoliposomes also yielded a dimer band on cross-linking. These data indicate that soluble and functionally reconstituted transhydrogenase possesses a dimeric structure.
mesh_terms: D000818:Animals; D002417:Cattle; D003432:Cross-Linking Reagents; D004119:Dimethyl Adipimidate; D004120:Dimethyl Suberimidate; D004220:Disulfides; D004591:Electrophoresis, Polyacrylamide Gel; D007096:Imidoesters; D008929:Mitochondria, Heart / Q000201:enzymology*; D008970:Molecular Weight; D009247:NADH, NADPH Oxidoreductases / Q000032:analysis*; D009250:NADP Transhydrogenases / Q000032:analysis*; D011487:Protein Conformation; D011817:Rabbits; D013388:Succinimides; D014508:Urea
chemical_list: D003432:Cross-Linking Reagents; D004220:Disulfides; D007096:Imidoesters; D013388:Succinimides; D004119:Dimethyl Adipimidate; D004120:Dimethyl Suberimidate; C029326:dimethyl pimelimidate; D014508:Urea; D009247:NADH, NADPH Oxidoreductases; D009250:NADP Transhydrogenases; C011240:dithiobis(succinimidylpropionate)