scholarly journals Monoamine oxidase A from human placenta and monoamine oxidase B from bovine liver both have one FAD per subunit

1989 ◽  
Vol 260 (3) ◽  
pp. 725-729 ◽  
Author(s):  
W Weyler
Keyword(s):  
Amino Acid ◽  
Monoamine Oxidase ◽  
Bovine Liver ◽  
Spectrophotometric Titration ◽  
Monoamine Oxidase A ◽  
Monoamine Oxidase B ◽  
Enzyme Preparations ◽  
Function Mechanism ◽  
Upper Limit ◽  
Quantitative Amino Acid Analysis

I present the first clear evidence that the protein: FAD ratio in human monoamine oxidase A and bovine monoamine oxidase B has an upper limit of 65 kDa and 57 kDa per FAD, respectively. To now it had been assumed that the protein: FAD ratio was 100-120 kDa to 1 FAD and that there was one FAD per two subunits which were assumed to be of the same size. For the present work the purity of monoamine oxidase A and monoamine oxidase B was improved over that previously achieved. Protein was determined by quantitative amino acid analysis and FAD content was measured by spectrophotometric titration of SDS-denatured enzyme with NaS2O4 standardized against riboflavin. The cause of the previous misassignment of the protein: FAD ratio was judged as having been due to the use of impure enzyme preparations. Knowledge of the correct protein: FAD ratio is important in devising cloning strategies for this enzyme, in understanding its structure, function, mechanism, and in the studies of its biosynthesis.

scholarly journals Oxidation of 3-amino-1-phenylprop-1-enes by monoamine oxidase and their use in a continuous assay of the enzyme

1988 ◽  
Vol 256 (3) ◽  
pp. 911-915 ◽  
Author(s):  
C H Williams ◽  
J Lawson ◽  
F R C Backwell
Keyword(s):  
Monoamine Oxidase ◽  
Absorption Coefficient ◽  
Mitochondrial Protein ◽  
Bovine Liver ◽  
Spectrophotometric Assay ◽  
Monoamine Oxidase A ◽  
Monoamine Oxidase B ◽  
High Absorption Coefficient ◽  
Continuous Assay ◽  
High Absorption

3-Amino-1-phenylprop-1-ene (cinnamylamine) and some derivatives were examined as substrates for monoamine oxidases A and B in mitochondria. All of the amines examined were readily oxidized by monoamine oxidase B but much less readily by monoamine oxidase A. E-Cinnamylamine was found to have Km 0.025 mM and Vmax. 3.9 nmol/min per mg of mitochondrial protein. Corresponding values with monoamine oxidase A were 0.026 mM and 0.85 nmol/min per mg respectively. Despite their different stereochemistry, E- and Z-N-methylcinnamylamines were almost equally effective as substrates for monoamine oxidase B. The characteristic u.v. absorbance and high absorption coefficient of cinnamaldehyde, the product produced by enzymic oxidation of cinnamylamine, is utilized in a sensitive continuous spectrophotometric assay for both enzymes in the rat and for the assay of a purified monoamine oxidase B from bovine liver.

scholarly journals Substrate and Inhibitor Specificities for Human Monoamine Oxidase A and B Are Influenced by a Single Amino Acid

2000 ◽  
Vol 276 (13) ◽  
pp. 9877-9882 ◽  
Author(s):  
Rani Maurice Geha ◽  
Igor Rebrin ◽  
Kevin Chen ◽  
Jean Chen Shih
Keyword(s):  
Amino Acid ◽  
Monoamine Oxidase ◽  
Monoamine Oxidase A ◽  
Single Amino Acid

scholarly journals Chronic monoamine oxidase-B inhibitor treatment blocks monoamine oxidase-A enzyme activity

2013 ◽  
Vol 121 (4) ◽  
pp. 379-383 ◽  
Author(s):  
Jasmin Bartl ◽  
Thomas Müller ◽  
Edna Grünblatt ◽  
Manfred Gerlach ◽  
Peter Riederer
Keyword(s):  
Enzyme Activity ◽  
Monoamine Oxidase ◽  
Monoamine Oxidase A ◽  
Monoamine Oxidase B ◽  
Inhibitor Treatment
Sign in / Sign up

Export Citation Format

Share Document