Biomaterial Database

A comparative study of some kinetic and molecular properties of microsomal and mitochondrial monoamine oxidase. 1988

N Gómez, and D Balsa, and M Unzeta

Departamento de Bioquímica y Biologia Molecular, Universidad Autonomade Barcelona, Spain.

This experimental work tries to characterize the monoamine oxidase of microsomal origin through its kinetic and molecular properties, and to establish a comparative study with the enzyme present in rat liver mitochondria. The temperature effect upon this catalytic activity was examined and similar behaviour of MAO A and MAO B between both cellular fractions was found. The study of the pH dependence of initial velocity showed similar results both in mitochondria and in microsomes. The FAD cofactor is covalently attached to the MAO of microsomal origin. The FAD containing subunits corresponding to MAO A and MAO B, previous binding of the enzyme with [3H]pargyline and posterior SDS electrophoresis and fluorography, showed molecular weights of 65,900 and 62,400, respectively, in both cellular fractions. The inhibition curves with clorgyline, deprenyl, semicarbazide and KCN, measuring the remaining activity towards 1 microM of benzylamine, indicated that in mitochondria 5% of the total activity is due to the presence of SSAO activity whereas in microsomes this activity represents about 20%. From all these results it appears that mitochondrial and microsomal MAO are related enzymes, although further structural studies are necessary to confirm their possible identity.

UI	MeSH Term	Description	Entries
D007700	Kinetics	The rate dynamics in chemical or physical systems.
D008862	Microsomes, Liver	Closed vesicles of fragmented endoplasmic reticulum created when liver cells or tissue are disrupted by homogenization. They may be smooth or rough.	Liver Microsomes,Liver Microsome,Microsome, Liver
D008930	Mitochondria, Liver	Mitochondria in hepatocytes. As in all mitochondria, there are an outer membrane and an inner membrane, together creating two separate mitochondrial compartments: the internal matrix space and a much narrower intermembrane space. In the liver mitochondrion, an estimated 67% of the total mitochondrial proteins is located in the matrix. (From Alberts et al., Molecular Biology of the Cell, 2d ed, p343-4)	Liver Mitochondria,Liver Mitochondrion,Mitochondrion, Liver
D008995	Monoamine Oxidase	An enzyme that catalyzes the oxidative deamination of naturally occurring monoamines. It is a flavin-containing enzyme that is localized in mitochondrial membranes, whether in nerve terminals, the liver, or other organs. Monoamine oxidase is important in regulating the metabolic degradation of catecholamines and serotonin in neural or target tissues. Hepatic monoamine oxidase has a crucial defensive role in inactivating circulating monoamines or those, such as tyramine, that originate in the gut and are absorbed into the portal circulation. (From Goodman and Gilman's, The Pharmacological Basis of Therapeutics, 8th ed, p415) EC 1.4.3.4.	Amine Oxidase (Flavin-Containing),MAO,MAO-A,MAO-B,Monoamine Oxidase A,Monoamine Oxidase B,Type A Monoamine Oxidase,Type B Monoamine Oxidase,Tyramine Oxidase,MAO A,MAO B,Oxidase, Monoamine,Oxidase, Tyramine
D011919	Rats, Inbred Strains	Genetically identical individuals developed from brother and sister matings which have been carried out for twenty or more generations or by parent x offspring matings carried out with certain restrictions. This also includes animals with a long history of closed colony breeding.	August Rats,Inbred Rat Strains,Inbred Strain of Rat,Inbred Strain of Rats,Inbred Strains of Rats,Rat, Inbred Strain,August Rat,Inbred Rat Strain,Inbred Strain Rat,Inbred Strain Rats,Inbred Strains Rat,Inbred Strains Rats,Rat Inbred Strain,Rat Inbred Strains,Rat Strain, Inbred,Rat Strains, Inbred,Rat, August,Rat, Inbred Strains,Rats Inbred Strain,Rats Inbred Strains,Rats, August,Rats, Inbred Strain,Strain Rat, Inbred,Strain Rats, Inbred,Strain, Inbred Rat,Strains, Inbred Rat
D004591	Electrophoresis, Polyacrylamide Gel	Electrophoresis in which a polyacrylamide gel is used as the diffusion medium.	Polyacrylamide Gel Electrophoresis,SDS-PAGE,Sodium Dodecyl Sulfate-PAGE,Gel Electrophoresis, Polyacrylamide,SDS PAGE,Sodium Dodecyl Sulfate PAGE,Sodium Dodecyl Sulfate-PAGEs
D005182	Flavin-Adenine Dinucleotide	A condensation product of riboflavin and adenosine diphosphate. The coenzyme of various aerobic dehydrogenases, e.g., D-amino acid oxidase and L-amino acid oxidase. (Lehninger, Principles of Biochemistry, 1982, p972)	FAD,Flavitan,Dinucleotide, Flavin-Adenine,Flavin Adenine Dinucleotide
D006631	Amine Oxidase (Copper-Containing)	A group of enzymes including those oxidizing primary monoamines, diamines, and histamine. They are copper proteins, and, as their action depends on a carbonyl group, they are sensitive to inhibition by semicarbazide.	Diamine Oxidase,Histaminase,Amine Oxidase, Copper-Containing,Copper Amine Oxidase,Diaminobenzidine Oxidase,Semicarbazide-Sensitive Amine Oxidase,Xylylene Diamine Oxidase,Amine Oxidase, Copper,Amine Oxidase, Copper Containing,Amine Oxidase, Semicarbazide-Sensitive,Copper-Containing Amine Oxidase,Diamine Oxidase, Xylylene,Oxidase, Copper Amine,Oxidase, Copper-Containing Amine,Oxidase, Diamine,Oxidase, Diaminobenzidine,Oxidase, Semicarbazide-Sensitive Amine,Oxidase, Xylylene Diamine,Semicarbazide Sensitive Amine Oxidase
D006863	Hydrogen-Ion Concentration	The normality of a solution with respect to HYDROGEN ions; H+. It is related to acidity measurements in most cases by pH	pH,Concentration, Hydrogen-Ion,Concentrations, Hydrogen-Ion,Hydrogen Ion Concentration,Hydrogen-Ion Concentrations
D000587	Oxidoreductases Acting on CH-NH Group Donors	Enzymes catalyzing the dehydrogenation of secondary amines, introducing a C	Secondary Amine Oxidoreductases,Amine Oxidoreductases, Secondary Amine,Amine Oxidoreductases, Secondary,Oxidoreductases Acting on CH NH Group Donors,Oxidoreductases, Secondary Amine