Lactobacillus diolivorans二醇脱水酶的分离纯化与酶学性质

Purification and characterization of diol dehydratase of Lactobacillus diolivorans

1，3-丙二醇（1，3-propanediol，1，3-PD）是一种重要的化工和医药中间体原料，是良好的溶剂、抗冻剂或保护剂，是聚酯——聚对苯二甲酸丙二醇酯（PTT）和聚氨酯的单体，可在地毯、纺织、工程塑料等领域中广泛应用，也可用于食品、化妆品和制药等行业食品．当前化工合成是生产1，3-丙二醇的主要方法，

Diol dehydratase of Lactobacillus diolivorans was purified by ammonium sulfate precipitation and gel filtration chromatography. The molecular mass of the native complex was estimated to be 200× 10^3 by nondenaturing polyacrylamide gel electrophoresis. Three main bands were present after SDS-PAGE with molecular masses of 62 × 10^3 , 35 × 10^3 and 22×10^3 , respectively. Km for the three main substrates were 1.3 mmol· L^-1 for 1,2-propanediol, 5.8 mmol ·L^-1 for glycerol and 10.3 mmol·L^-1 for 1, 2- ethanediol. Km for adenosylcobalamin coenzyme was 1.5 μmol·L^-1, which was required for the enzyme catalysis. The optimal reaction conditions of the enzyme were pH 8. 6 and 37℃.