从乳酸克鲁维酵母中分离出的一种可诱导β-半乳糖苷酶的纯化及性质

Dickson R C, Dickson L R, Markin J S

J Bacteriol. 1979 Jan;137(1):51-61. doi: 10.1128/jb.137.1.51-61.1979.

beta-Galactosidase (EC 3.2.1.32) was purified 80-fold from the yeast Kluyveromyces lactis induced for this enzyme by growth on lactose. When the purified enzyme was subjected to electrophoresis on an acrylamide gel in the presence of sodium dodecyl sulfate, one protein with an apparent molecular weight of 135,000 was observed. The enzyme has a sedimentation coefficient of 9.6S. This beta-galactosidase and the one from Escherichia coli are not antigenically related. Maximal enzyme activity requires Na+ and Mn2+ and a reducing agent. beta-Galactosidase has Km values of 12 to 17 and 1.6 mM for lactose and o-nitrophenyl-beta-D-galactoside, respectively. The hydrolase and transgalactosylase activities of the enzyme are similar to those of E. coli beta-galactosidase.

β-半乳糖苷酶（EC 3.2.1.32）通过在乳糖上生长诱导该酶产生的乳酸克鲁维酵母中纯化了80倍。当纯化的酶在十二烷基硫酸钠存在下在丙烯酰胺凝胶上进行电泳时，观察到一种表观分子量为135,000的蛋白质。该酶的沉降系数为9.6S。这种β-半乳糖苷酶与大肠杆菌的β-半乳糖苷酶无抗原相关性。最大酶活性需要Na +和Mn2 +以及一种还原剂。β-半乳糖苷酶对乳糖和邻硝基苯基-β-D-半乳糖苷的Km值分别为12至17和1.6 mM。该酶的水解酶和转半乳糖苷酶活性与大肠杆菌β-半乳糖苷酶的活性相似。