l-Methionine γ-lyase from Pseudomonas putida and Aeromonas

摘要: Publisher Summary This chapter describes the assay method, purification procedures, and general properties of L-methionine γ -lyase from Pseudomonas putida (P. putida) Aeromonas. L-Methionine γ-lyase catalyzes α, γ-elimination L- methionine to produce α-ketobutyrate, methanethiol, ammonia. The enzyme has been purified Clostridium sporogenes, enzymatic can be routinely followed by spectrophotometric determination α-ketobutyrate with 3-methyl-2-benzothiazolone hydrazone hydrochloride. In case preparation P. putida, ICR 3460 is grown in a medium containing 0.25% L-methionine, 0.1% polypeptone, glycerol, KH2PO4, K2HPO4, 0.01% MgSO4·7H2O, 0.025% yeast extract at 28° for 18 hr shaking. crystallized vapor diffusion method McPherson. also Aeromonas sp. 3470 essentially same as described using DEAE-Toyopearl 650 M DE AE- Sephadex A-50 column chromatography. About 30 mg homogeneous (specific activity, 31 units/mg) obtained crude 204 g wet cells (total protein, 4.6 g; specific 1.04 units/rag), an overall yield 20%.