链霉菌G4溶菌酶的产生条件及特性

对链霉菌G4的产酶发酵条件和溶菌特性进行研究结果表明:蔗糖30 g/L、大豆蛋白胨12.5 g/L、牛肉膏2 g/L,对产酶最为有利;G4溶菌酶最适培养温度33 ℃,培养时间72 h,培养基初始pH 8.G4溶菌酶的最适作用温度和最适作用pH分别是55 ℃和6.5,多数金属离子会抑制G4溶菌酶的活性,其中Zn2+、Cu2+、Fe2+、 Pb2+几乎可以使其完全失活;对几种细菌、酵母菌的研究表明,G4溶菌酶对卵清溶菌酶不能作用的变形链球菌和金黄色葡萄球菌有很强的溶解活性.

Production of bacteriolytic enzyme by Stretomyces sp. G4 and its properities of produced G4 enzymes

Fermentation conditions and bacteriolytic properties of Streptomyces sp.G4 were investigated.The results showed that the maximum yield of the bacteriolytic enzyme G4 was obtained from the medium containing sucrose 30 g/L,soybean peptone 12.5 g/L and beef extract 2 g/L.The optimum fermentation temperature was 33 ℃ with incubation time of 72 h,initial pH of 7.5.The optimum reaction temperature and pH of the enzyme were 65 ℃ and 6.5,respectively.Metal ions inhibited the activity of lysozyme G4,in which Zn2＋,Cu2＋,Fe2＋,and Pb2＋ deactivated the enzyme completely.According to lyse-some bacteria and yeast,G4 lysozyme had a broader bacteriolytic spectrum having high activity against Streptococcus mutans and Staphylococcus aureus which were resistant to egg-white lysozyme.