title: [Effect of solubilization by methylethyl ketone of mitochondrial monoamine oxidase of the rat liver on the kinetic properties of the enzyme].
abstract: The values of Km and V for serotonin, tyramine and beta-phenylethylamine deamination by solubilized and partially purified preparations of monoamine oxidase (MAO) from rat liver were determined. As a result of MAO solubilization by methylethylketone, 14% of activity localized in the mitochondria passed into solution. Subsequent chromatography on AH-Sepharose 4B resulted in 27-fold purification of the enzyme with a 9% yield. In experiments with membrane-bound and partially purified MAO, the Km and V values were shown to increase non-competitively with a rise in O2 concentration. In contrast with intact mitochondria, the use of partially purified MAO preparations led to a loss of the enzyme sensitivity to O2 depending on the nature of the amine. The dependence of kinetic properties of MAO on the lipid environment of mitochondrial membranes is discussed.
mesh_terms: D000818:Animals; D002074:Butanones / Q000494:pharmacology*; D066298:In Vitro Techniques; D007700:Kinetics; D008297:Male; D008930:Mitochondria, Liver / Q000201:enzymology*; D008995:Monoamine Oxidase / Q000378:metabolism*; D010100:Oxygen / Q000378:metabolism; D010627:Phenethylamines / Q000378:metabolism; D051381:Rats; D012701:Serotonin / Q000378:metabolism; D012995:Solubility; D013379:Substrate Specificity / Q000187:drug effects; D014439:Tyramine / Q000378:metabolism
chemical_list: D002074:Butanones; D010627:Phenethylamines; C029261:phenethylamine; D012701:Serotonin; C005222:methylethyl ketone; D008995:Monoamine Oxidase; D010100:Oxygen; D014439:Tyramine
vernacular_title: Vliianie soliubilizatsii mitokhondrial'noĭ monoaminoksidazy pecheni krysy metilétilketonom na kineticheskie svoĭstva fermenta.