Enzymatic preparation of α- and β-deuterated or tritiated amino acids with l-methionine γ-lyase

✍ Scribed by Nobuyoshi Esaki; Seiji Sawada; Hidehiko Tanaka; Kenji Soda

• Publisher: Elsevier Science
• Year: 1982
• Tongue: English
• Weight: 361 KB
• Volume: 119
• Category: Article
• ISSN: 0003-2697
• DOI: 10.1016/0003-2697(82)90586-3

✦ Synopsis

L-Methionine y-lyase catalyzes the exchange of LY-and @-hydrogens of L-methionine and S-methyl-L-cysteine with deuterium or tritium of solvents. The rate of a-hydrogen exchange with deuterium was about 40 times faster than that of the elimination reactions. The deuterium and tritium were exchanged also with the (Y-and /3-hydrogens of the straight-chain amino acids which do not undergo the elimination: L-alanine, L-a-aminobutyrate, L-norvaline, and L-norleucine. No exchange occurs for the D-isomers, acidic L-amino acids, basic L-amino acids, and branched-chain L-amino acids, although a-hydrogen of glycine, L-tryptophan, and Lphenylalanine is exchanged slowly. These enzymatic hydrogen-exchange reactions facilitate specific labeling of the L-amino acids with deuterium and tritium.