Veeraragavan K, Colpitts T, Gibbs B F
Protein Engineering Section, National Research Council of Canada, Montreal.
Biochim Biophys Acta. 1990 May 1;1044(1):26-33. doi: 10.1016/0005-2760(90)90214-i.
Lipase, an enzyme that hydrolyzes triacylglycerol, has been purified and characterized. The purification procedure includes ethanol precipitation and chromatographies on Sephacryl-200 HR, high resolution anion-exchange (mono Q) and Polybuffer exchanger 94. With this procedure, two forms of lipases from Geotrichum candidum were obtained. Lipase I (main enzyme) and lipase II (minor enzyme) were purified 35-fold with a 62% recovery in activity and 94-fold with a 18% recovery in activity, respectively. Their molecular weights have been estimated by polyacrylamide gel electrophoresis under denaturing conditions and by molecular sieving under native conditions at 56,000. Lipase I and II had optimum pH values of 6.0 and 6.8 and isoelectric points of 4.56 and 4.46, respectively. The enzymes are stable at a pH range of 6.0 to 8.0. Monovalent ions had little effect on both enzyme activities, while divalent ions at concentrations above 50 mM inhibited the lipase activities in a concentration-dependent manner. Sodium dodecyl sulfate at a concentration lower than 10 mM completely inhibited the lipase activity.
脂肪酶是一种能水解三酰甘油的酶，已被纯化并进行了特性鉴定。纯化过程包括乙醇沉淀以及在Sephacryl - 200 HR、高分辨率阴离子交换柱（Mono Q）和聚缓冲剂交换柱94上的色谱分离。通过该方法，从白地霉中获得了两种形式的脂肪酶。脂肪酶I（主要酶）和脂肪酶II（次要酶）的纯化倍数分别为35倍，活性回收率为62%；94倍，活性回收率为18%。它们的分子量已通过变性条件下的聚丙烯酰胺凝胶电泳和天然条件下的分子筛法估计为56,000。脂肪酶I和II的最适pH值分别为6.0和6.8，等电点分别为4.56和4.46。这些酶在pH值6.0至8.0的范围内稳定。单价离子对两种酶的活性影响很小，而浓度高于50 mM的二价离子以浓度依赖的方式抑制脂肪酶的活性。浓度低于10 mM的十二烷基硫酸钠完全抑制脂肪酶的活性。
