Methionine gamma-lyase

In enzymology, a methionine gamma-lyase is an enzyme that catalyzes the chemical reaction


 * L-methionine + H2O $$\rightleftharpoons$$ methanethiol + NH3 + 2-oxobutanoate

Thus, the two substrates of this enzyme are L-methionine and H2O, whereas its 3 products are methanethiol, NH3, and 2-oxobutanoate.

This enzyme belongs to the family of lyases, specifically the class of carbon-sulfur lyases. The systematic name of this enzyme class is L-methionine methanethiol-lyase (deaminating 2-oxobutanoate-forming). Other names in common use include L-methioninase, methionine lyase, methioninase, methionine dethiomethylase, L-methionine gamma-lyase, and L-methionine methanethiol-lyase (deaminating). This enzyme participates in selenoamino acid metabolism. It employs one cofactor, pyridoxal phosphate.

Structural studies
As of late 2007, 8 structures have been solved for this class of enzymes, with PDB accession codes, , , , , , , and.