%0 Journal Article %T 重组嗜热乳糖酶在毕赤酵母中的表达、纯化与活性分析 %A 李洪波 %A 罗海燕 %A 张树琴 %A 吴东海 %J 食品与生物技术学报 %D 2018 %R 10.3969/j.issn.1673-1689.2018.08.005 %X 为获得耐高温的重组乳糖酶,PCR扩增激烈热球菌(Pyrococcus furious)乳糖酶基因、构建毕赤酵母分泌型表达载体pPICZαA/Lac并转化毕赤酵母X-33菌株。重组酵母转化子经甲醇诱导,重组嗜热乳糖酶实现了分泌表达并经蛋白印迹验证。纯化前上清液中乳糖酶总活力高达125 U/mL,经镍亲合纯化得重组酶,SDS-PAGE显示其纯度在95%以上,比活力1 800 U/mg,该酶最适温度在105 ℃左右且热稳定性好,具有很强的水解乳糖能力。</br>In order to obtain the recombinant thermostable lactase,a DNA fragment containing the mature lactase gene was amplified from Pyrococcus furious by PCR and cloned into pPICZaA,generating a fusion protein with the alpha factor from baker's yeast and integrated into the genome of Pichia pastoris strain X-33. Recombinant yeast transformants with high-level recombinant lactase production was identified by Western blotting,secreting as much as 125 U/mL induction by methanol. The recombinant thermostability lactase was purified by Ni+-NTA affinity chromatography and SDS-PAGE results shown that the purity was over 95%. The specific activity was about 1 800 U/mg and the optimal temperature was about 105 ℃. It was also showed that the purified lactase from P. pastoris has a highly thermostability and strong ability to hydrolysis lactose %K 嗜热乳糖酶 激烈热球菌 毕赤酵母 分泌表达 纯化< %K /br> %K thermophile lactase %K Pyrococcus furious %K Pichia pastoris %K secretory expression %K purification %U http://spyswjs.cnjournals.com/spyswjs/ch/reader/view_abstract.aspx?file_no=201808005&flag=1