This model describes a methionine gamma-lyase subset of a family of PLP-dependent trans-sulfuration enzymes. The member from the parasite Trichomonas vaginalis is described as catalyzing alpha gamma- and alpha-beta eliminations and gamma-replacement reactions on methionine, cysteine, and some derivatives. Likewise, the enzyme from Pseudomonas degrades cysteine as well as methionine. [Energy metabolism, Amino acids and amines]