Methionine gamma-lyase from Pseudomonas putida is a PLP-dependent enzyme which plays a central role in sulfur amino acid metabolism. METase catalyzes the ,γ-elimination of methionine to -ketobutyrate,methanethiol,and ammonia. METase also catalyzes the ,γ-elimination of other sulfur containing amino acids,such as homocysteine,cysteine. Because of its ability to deplete methionine,METase has been considered as a viable component of cancer therapeutics against methionine-dependent tumor cells. METase has also been utilized to design drug targets for the infectious diseases caused by parasitic protozoa and anaerobic periodontal bacteria.