Enzymatic reaction of β- N-methylaminoalanine with l-amino acid oxidase

• Published in: Biochimica et biophysica acta Vol. 1074; no. 1; pp. 36 - 39
• Main Authors: Hashmi, Mazzaz, Anders, M.W.
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 24.05.1991; Elsevier
• Subjects: Amino Acid Oxidoreductases - chemistry; Amino Acids, Diamino - chemistry; Analytical, structural and metabolic biochemistry; Biological and medical sciences; Carcinogens - chemistry; Catalase - chemistry; Enzymes and enzyme inhibitors; Fundamental and applied biological sciences. Psychology; Kinetics; L-Amino Acid Oxidase; Molecular Structure; N-Methylglycine; Neurotoxic amino acid; Oxidoreductases; Potassium Cyanide - chemistry; Semicarbazides - chemistry; β- N-Methylaminoalanine; β- N-Methylaminopyruvate; l-Amino acid oxidase; BMAA; PD; β- N-Methylaminopyruvate; Neurotoxic amino acid; ALS; l-AAO; N-Methylglycine; β- N-Methylaminoalanine; Alanine; Enzymatic activity; Enzyme; Aminoacid; Reaction product; L-Amino-acid oxidase; Reaction mechanism; NMR spectrometry; Kinetics; Derived product
• DOI: 10.1016/0304-4165(91)90035-F
• ISSN: 0304-4165; 0006-3002

The reaction of β- N-methylaminoalanine (BMAA) with l-amino acid oxidase ( l-AAO) in the presence of catalase yields ammonia and β- N-methylaminopyruvate, which was trapped as its 2,4-dinitrophenylhydrazone, as products. Incubation of BMAA with l-AAO in the presence of semicarbazide led to the formation of a semicarbazone, indicating intermediate iminium ion formation; when potassium cyanide (5 mM) was added, semicarbazone formation was blocked. The formation of β- N-methylaminopyruvate was decreased by omission of catalase and was reduced in the presence of hydrogen peroxide (100 mM). These results indicate that BMAA is converted by l-AAO to the corresponding α-imino acid, which undergoes hydrolysis to β- N-methylaminopyruvate. The α-keto acid is readily oxidized to N-methyllycine by hydrogen peroxide.