柞蚕溶菌酶基因在酵母中的表达及对变形链球菌的作用

目的:建立柞蚕溶菌酶的毕赤酵母表达系统,分析重组的柞蚕溶菌酶对变形链球菌的作用。方法:毕赤酵母表达系统用于柞蚕溶菌酶的表达及纯化。琼脂扩散法用于检测重组柞蚕溶菌酶对变形链球菌的抗菌活性。结果:在毕赤酵母表达系统中表达的柞蚕溶菌酶能够分泌到胞外,并且被糖基化。抑菌圈结果显示重组柞蚕溶菌酶对变形链球菌有抑菌活性。柞蚕溶菌酶在酵母菌中的表达是在5ml/L甲醇诱导下96h达到高峰;纯化的重组柞蚕溶菌酶相对分子质量约为20000。结论:重组的柞蚕溶菌酶具有抑制变形链球菌生长的作用。

Expression of a lysozyme from antheraea pernyi in pastoris and the effects of recombinant Ap-lysozyme on Streptococcus mutans

Objective: To construct the antheraea pernyi lysozyme(ApLZ) expression system using the methylotrophic yeast Pichia pastoris, to assay the antibacterial activity of the recombinant ApLZ against Streptococcus mutans. Methods:The ApLZ expression system was used in the expression and purity of Ap-lysozyme. The antibacterial activity of the recombinant ApLZ against Streptococcus mutans were assayed by using agar diffusion method. Results:Expression system of ApLZ was constructed using the methylotrophic yeast Pichia pastoris as a host. ApLZ was expressed correctly and secreted efficiently when the native signal sequence of ApLZ was used as secretion signal. The level of ApLZ expression in Pichia pastoris peaks at 96 h after the induction of sustaining 5 ml/L methanol. The molecular weight of the recombinant ApLZ is about 20 000. Conclusion:The recombinant ApLZ is active in inhibiting the growth of Streptococcus mutans.