Binding of dicyclohexylcarbodiimide to a native F1-ATPase-inhibitor protein complex isolated from bovine heart mitochondria.
The effect and the binding of dicyclohexylcarbodiimide (DCCD) to a soluble native F1-ATPase-inhibitor protein complex (F1-IP) isolated from heart mitochondria was studied. About one mol DCCD bound per mol F1-IP complex; this inhibited its ATPase activity by more than 95%, ever under conditions that led to maximal hydrolysis. Bound DCCD localized to beta-subunits of the F1-IP complex. Cross-linking of the DCCD labeled complex with N-(ethoxy-carbonyl)-2-ethoxydihydroquinoline yielded a protein with a Mr 65,000-67,000 that contained IP as evidenced by its reaction with IP antibodies. No alpha-subunits were detected in this cross-linked product. The Mr 65,000-67,000 protein corresponds to beta-subunits cross-linked with IP (Klein et al, Biochemistry 1980; 19, 2919-2925). However, no DCCD was found in the cross-linked beta-subunit-IP product of labeled native F1-IP. Thus the beta-subunit in contact with IP is distinct from the other two beta-subunits of the enzyme.
D000818:Animals; D002234:Carbodiimides / Q000378:metabolism*; D002352:Carrier Proteins / Q000378:metabolism*; D002417:Cattle; D003432:Cross-Linking Reagents; D004024:Dicyclohexylcarbodiimide / Q000378:metabolism*; D004591:Electrophoresis, Polyacrylamide Gel; D008929:Mitochondria, Heart / Q000201:enzymology* / Q000378:metabolism; D011506:Proteins / Q000302:isolation & purification / Q000378:metabolism* / Q000502:physiology; D006180:Proton-Translocating ATPases / Q000037:antagonists & inhibitors* / Q000378:metabolism; D013367:Submitochondrial Particles / Q000201:enzymology; D000097795:ATPase Inhibitory Protein
D002234:Carbodiimides; D002352:Carrier Proteins; D003432:Cross-Linking Reagents; D004024:Dicyclohexylcarbodiimide; D011506:Proteins; D006180:Proton-Translocating ATPases; D000097795:ATPase Inhibitory Protein