Investigation of localization of monoamine oxidase (EC 1.4.3.4) in subfraction of rat liver mitochondria.
Subfractionation of the purified preparations of mitochondria was performed according to Schnaitman's digitonin method. In some experiments, polyvinyl sulphate (PVS) was added to the medium during the preparation and subfractionation of mitochondria. The formation of the "fluffy layer" was not observed in the presence of PVS. The "fluffy layer" was either removed or left within the pellet during the separation of the subfraction of mitoplasts from the supernate containing the outer membrane as well as the inter-membrane space. The monoamine oxidase (MAO) activity was determined by means of our own modification of Tabor's method. In this way the influence of aldehyde oxidase upon the obtained results could be eliminated. A part of MAO activity was found in the subfraction of mitoplasts both in the presence and absence of PVS in the medium. The obtained results suggest double localization of MAO both in the outer and inner membrane. The influence of the method of determination of MAO activity on the evaluation of its intra-mitochondrial activity has been discussed.
D000154:Aconitate Hydratase / Q000032:analysis; D000818:Animals; D002458:Cell Fractionation; D004072:Digitonin; D005260:Female; D005649:Fumarate Hydratase / Q000032:analysis; D008297:Male; D008566:Membranes / Q000201:enzymology; D008930:Mitochondria, Liver / Q000201:enzymology* / Q000648:ultrastructure; D008995:Monoamine Oxidase / Q000032:analysis*; D051381:Rats; D013347:Subcellular Fractions / Q000201:enzymology; D013385:Succinate Dehydrogenase / Q000032:analysis
D013385:Succinate Dehydrogenase; D008995:Monoamine Oxidase; D005649:Fumarate Hydratase; D000154:Aconitate Hydratase; D004072:Digitonin