cystathionine γ-lyase

cys·ta·thi·o·nine γ-ly·ase (sis″tə-thiґo-nēn liґās) [EC 4.4.1.1] an enzyme of the lyase class that catalyzes the cleavage of cystathionine to cysteine, α-ketoglutarate, and ammonia as a step in the metabolism of methionine. It is a pyridoxal-phosphate protein and the reaction occurs in the liver. Deficiency of the enzyme, an autosomal recessive trait, results in cystathioninuria. Called also γ-cystathionase.