热稳定性对甲基对硫磷水解酶在毕赤酵母中分泌的影响  

Effects of Thermal Stability on Secretion of Methyl-parathion Hydrolase in Pichia pastoris

作　　者：龚攀[1,2] 范家佑[1] 田健[2] 伍宁丰[2] 初晓宇[2] 

机构地区：[1]贵州大学药学院,贵阳550025 [2]中国农业科学院生物技术研究所,北京100081

出　　处：《中国农业科技导报》2015年第3期42-48,共7页Journal of Agricultural Science and Technology

基　　金：国家863计划项目(2013AA102804);国家自然科学基金项目(31100049)资助

摘　　要：甲基对硫磷水解酶可生物降解有机磷农药,由于其特殊的应用价值,越来越受到人们的关注。来源于苍白杆菌的甲基对硫磷水解酶MPH-Och在毕赤酵母系统中不能有效地分泌表达。将热稳定性提高的突变体MPH-S274Q在毕赤酵母中表达,发现其毕赤酵母重组菌株经摇瓶诱导培养120 h后,培养上清的酶活力达到0.7 U/m L,蛋白分泌量是野生型的14倍,SDS-PAGE电泳图中培养上清有明显的蛋白质条带,进一步证明了分泌效率提高,该结果表明提高蛋白质的热稳定性可以作为提高外源蛋白在毕赤酵母中的分泌效率的一条有效途径。Methyl parathion hydrolase can biodegrade organophosphorus pesticides. Due to its special application value, researchers paid more and more attension. Wild-type MPH-Och from Ochrobactrum sp. could not be secreted in Pichia pastoris. In order to increase the secretion level, the MPH-S274Q mutant, which thermal stability was increased, was expressed in Pichia pastoris. After recombinant strain was induced by shaking culture flask for 120 h, the enzyme activity of culture supernatant reached 0.7 U/mL. It was 14 times of that in wild type MPH-Oeh. The SDS- PAGE electrophoresis showed that the culture supernatant of mutant MPH-S274Q had a distinct protein band, which further proved the improvement of secretion efficiency. This study indicated that improving protein thermal stability can be an effective way to increase secretion efficiency of exogenous protein in Pichia pastoris.

关 键 词：甲基对硫磷水解酶 分泌 热稳定性 毕赤酵母 

分 类 号：Q814[生物学—生物工程]