title: Sulfhydryl groups are involved in H+ translocation via the uncoupling protein of brown adipose tissue mitochondria.
abstract: Mersalyl inhibits H+ transport via the uncoupling protein (UP) in brown adipose tissue (BAT) mitochondria estimated as swelling in potassium acetate (Ki 67 microM) or as valinomycin-induced H+ extrusion in K2SO4 (Ki 55 microM) and KCl. The swelling in KCl is depressed only slightly. Some other SH-reagents (p-hydroxymercuribenzoate, 5,5'-dithiobis(2-nitrobenzoate) and thiolyte DB), but not hydrophobic reagents (N-ethylmaleimide and eosin-5-maleimide), exhibit analogous inhibition. Thus an essential SH-group localized at the water-accessible cytosolic surface of UP was found to be involved in H+ transport via UP but not in Cl- transport.
mesh_terms: D002001:Adipose Tissue, Brown / Q000378:metabolism*; D000818:Animals; D001692:Biological Transport; D002352:Carrier Proteins; D006224:Cricetinae; D007473:Ion Channels; D007700:Kinetics; D008565:Membrane Proteins / Q000378:metabolism*; D008634:Mersalyl / Q000494:pharmacology; D008928:Mitochondria / Q000378:metabolism*; D024101:Mitochondrial Proteins; D011522:Protons; D013438:Sulfhydryl Compounds / Q000378:metabolism; D013439:Sulfhydryl Reagents / Q000494:pharmacology*; D000071256:Uncoupling Protein 1; D014634:Valinomycin / Q000494:pharmacology
chemical_list: D002352:Carrier Proteins; D007473:Ion Channels; D008565:Membrane Proteins; D024101:Mitochondrial Proteins; D011522:Protons; D013438:Sulfhydryl Compounds; D013439:Sulfhydryl Reagents; D000071256:Uncoupling Protein 1; D014634:Valinomycin; D008634:Mersalyl