Effect of lipid depletion on the kinetics of microsomal NADH-cytochrome C reductase.
Removal of lipids from the microsomes with 90% acetone resulted in 50% or more decrease of NADH-cytochrome c reductase activity. The decrease of the enzyme activity was a result of lowering of Vmax and increase in Km. When sufficient amounts of phosphatidylserine or phosphatidylinositol were added to the acetone-treated microsomes, the reductase activity was restored completely to the original level. On the other hang, when ferricyanide was used in place of cytochrome c as electron acceptor, the rate of reduction of ferricyanide was not affected by the lipid depletion and Vmax and Km for ferricyanide remained unchanged.
D000818:Animals; D002645:Chickens; D003579:Cytochrome Reductases / Q000378:metabolism*; D005260:Female; D007700:Kinetics; D050356:Lipid Metabolism; D008297:Male; D008862:Microsomes, Liver / Q000201:enzymology*; D009247:NADH, NADPH Oxidoreductases / Q000378:metabolism; D009251:NADPH-Ferrihemoprotein Reductase / Q000378:metabolism*; D010716:Phosphatidylinositols / Q000378:metabolism; D010718:Phosphatidylserines / Q000378:metabolism
D010716:Phosphatidylinositols; D010718:Phosphatidylserines; D009247:NADH, NADPH Oxidoreductases; D003579:Cytochrome Reductases; D009251:NADPH-Ferrihemoprotein Reductase