捕食性真菌Duddingtonia flagrans胞外蛋白质的生化性质研究  

Purification and biochemical properties studies of extracellular proteins from Duddingtonia flagrans

作　　者：王瑞[1] 孙晓燕 马亚囡 杨晓野[1] 杨莲茹[1] 赵晓慧[1] 李军燕[1] 牛广胜[1] 张磊[1] 

机构地区：[1]内蒙古农业大学兽医学院农业部动物疾病临床诊疗技术重点实验室,内蒙古呼和浩特010018 [2]山东省即墨市动物疫病预防与控制中心,山东即墨266200 [3]内蒙古伊利实业集团股份有限公司原奶事业部,内蒙古呼和浩特010080

出　　处：《中国兽医科学》2015年第8期776-780,共5页Chinese Veterinary Science

基　　金：公益性行业(农业)科研专项(201303037);国家自然科学基金项目(31460656;31060338);内蒙古自然科学基金项目(2014MS0339;2015MS0308);内蒙古农业大学大学生科技创新基金项目(2014年)

摘　　要：为纯化捕食性真菌Duddingtonia flagrans分泌的胞外蛋白酶并研究其生化性质,利用枸橼酸液体培养基对D.flagrans进行培养,以灭菌的马圆线虫进行诱导,之后用盐析法粗提培养液,再使用Sephadex G-100分子筛进行层析纯化,最后对纯化物进行最适pH、温度及蛋白酶抑制剂的抑制试验。结果显示,被纯化出的3种胞外蛋白酶的分子质量分别为38、63、19ku;在pH 6.0~7.0、45~55℃条件下,其活性最高;它们都对酶抑制剂菲罗啉和抑肽素非常敏感,其中38ku的蛋白酶对抑制剂PMSF也很敏感。上述结果为进一步研究捕食性真菌分泌的胞外蛋白酶在杀线虫过程中的作用以及今后在生产中的具体应用提供了重要参考依据。To purify extracellular proteases of Duddingtonia flagrans and study their biochemical properties,citric acid nutrient medium with Strongylus equinus was used to culture D. flagrans. Then the crude extracts of extracellular proteases were obtained by salt fractionation and further purified with Sephadex G-100 chromatograph. Finally, the effect of p H, temperature, protease inhibitors on the enzymic activity of these proteases was tested. The results showed that three extracellular proteases were purified and their molecular weight were 38 ku,63 ku and 19 ku,respectively. Enzymic activity was highest at pH 6.0 to 7.0 and at 45 ℃ to 55℃C. The enzymic activity of three purified proteins was affected by phenanthroline and pepstatin,while extracellular protease of 38 ku was affected by PMSF too. The above results provided an important information for further studying the function of extracellular protease from D. flagrans and specific application in practice.

关 键 词：捕食性真菌 Duddingtonia flagrans 胞外蛋白质 纯化 生化性质 

分 类 号：S852.66[农业科学—基础兽医学]