Forage R G, Foster M A
Biochim Biophys Acta. 1979 Aug 15;569(2):249-58. doi: 10.1016/0005-2744(79)90060-3.
Diol dehydratase (1,2-propanediol hydro-lyase, EC 4.2.1.28) and glycerol dehydratase (glycerol hydro-lyase, EC 4.2.1.30) are shown to be distinct, separable enzymes that occur individually or together in different strains of Klebsiella sp. Anaerobic growth with propan-1,2-diol induces diol dehydratase alone, whereas glycerol fermentation induces both enzymes in K. pneumoniae ATCC 25955 and in Citrobacter freundii NCIB 3735. The dehydratases can be resolved by polyacrylamide-gel electrophoresis or separated by anion-exchange chromatography alone. Sucrose density gradient centrifugation failed to distinguish the enzymes and indicated a molecular weight of 1.9 . 10(5) for both. The enzymes can be assayed individually, even when present in the same crude extract, using the 67-fold difference in their Km values for coenzyme B-12. For both enzymes inactivation kinetics are observed with glycerol as substrated, and monovalent cations influence both the inactivation rate and catalytic rate of the reaction.
二醇脱水酶（1,2-丙二醇水解酶，EC 4.2.1.28）和甘油脱水酶（甘油水解酶，EC 4.2.1.30）被证明是不同的、可分离的酶，它们在克雷伯氏菌属的不同菌株中单独或共同存在。以1,2-丙二醇进行厌氧生长仅诱导二醇脱水酶，而在肺炎克雷伯氏菌ATCC 25955和弗氏柠檬酸杆菌NCIB 3735中，甘油发酵则诱导这两种酶。脱水酶可以通过聚丙烯酰胺凝胶电泳分离，或仅通过阴离子交换色谱法分离。蔗糖密度梯度离心未能区分这两种酶，且表明两者的分子量均为1.9×10⁵ 。即使两种酶存在于同一粗提物中，也可以利用它们对辅酶B-12的Km值相差67倍这一点来分别进行测定。对于这两种酶，以甘油作为底物时均观察到失活动力学，并且单价阳离子会影响反应的失活速率和催化速率。
