Effect of cetyltrimethylammonium on ATP hydrolysis and proton translocation in the F0-F1 H+-ATP synthase of mitochondria.
The amphiphylic alkyl cation cetyltrimethylammonium inhibits the catalytic activity of soluble and membrane-bound F1 in a noncompetitive fashion. In sonic submitochondrial particles the Dixon plot showed a peculiar pattern with upward deviation at cetyltrimethylammonium concentration higher than 80 microM. In membrane-bound F1 the inhibition by cetyltrimethylammonium was potentiated by the F0 inhibitor ologomycin. Cetyltrimethylammonium also inhibited the oligomycin-sensitive proton conductivity in F1-containing particles but was without any effect in F1-depleted particles. Also this inhibitory effect was potentiated by oligomycin. These results indicate functional cooperative interactions between F0 and F1.
Bârzu
O
O
Institute of Medical Biochemistry and Chemistry, University of Bari, Italy.
Guerrieri
F
F
Scarfò
R
R
Capozza
G
G
Papa
S
S
D000255:Adenosine Triphosphate / Q000378:metabolism*; D000818:Animals; D002462:Cell Membrane / Q000187:drug effects / Q000201:enzymology; D000077286:Cetrimonium; D002593:Cetrimonium Compounds / Q000494:pharmacology*; D004357:Drug Synergism; D005990:Glycerol / Q000494:pharmacology; D006493:Heparin / Q000494:pharmacology; D006868:Hydrolysis; D007700:Kinetics; D008928:Mitochondria / Q000187:drug effects / Q000201:enzymology*; D009840:Oligomycins / Q000494:pharmacology; D006180:Proton-Translocating ATPases / Q000037:antagonists & inhibitors*; D011522:Protons; D000644:Quaternary Ammonium Compounds / Q000494:pharmacology*
D002593:Cetrimonium Compounds; D009840:Oligomycins; D011522:Protons; D000644:Quaternary Ammonium Compounds; D000255:Adenosine Triphosphate; D006493:Heparin; D006180:Proton-Translocating ATPases; D005990:Glycerol; D000077286:Cetrimonium