IUBMB Enzyme Nomenclature


Accepted name: methionine γ-lyase

Reaction: L-methionine + H2O = methanethiol + NH3 + 2-oxobutanoate (overall reaction)
(1a) L-methionine = methanethiol + 2-ammoniobut-2-enoate
(1b) 2-ammoniobut-2-enoate + H2O = 2-oxobutanoate + NH3 (spontaneous)

For diagram click here.

Other name(s): L-methioninase; methionine lyase; methioninase; methionine dethiomethylase; L-methionine γ-lyase; L-methionine methanethiol-lyase (deaminating)

Systematic name: L-methionine methanethiol-lyase (deaminating; 2-oxobutanoate-forming)

Comments: A pyridoxal-phosphate protein.

Links to other databases: BRENDA, EXPASY, KEGG, UM-BBD, Metacyc, PDB, UM-BBD, CAS registry number: 42616-25-1


1. Kreis, W. and Hession, C. Isolation and purification of L-methionine-α-deamino-γ-mercaptomethane-lyase (L-methioninase) from Clostridium sporogenes. Cancer Res. 33 (1973) 1862-1865. [PMID: 4720797]

[EC created 1976]

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