Ni Xiumei, Yue Lixi, Li Jing, Chi Zhenming, Liu Zhiqiang, Madzak Catherine
Unesco Chinese Center of Marine Biotechnology, Ocean University of China, Yushan Road, No. 5, Qingdao, China.
Indian J Biochem Biophys. 2009 Aug;46(4):294-8.
ALP2 gene encoding alkaline protcase cloned from Aureobasidium pullulans HN2-3 was ligated into the surface display plasmid and expressed in the cells of the yeast Yarrowia lipolytica. The expressed alkaline protease was immobilized on the yeast cells. The activity of the immobilized enzyme with 6 x His tag was found to be significantly higher than that of without 6 x His tag. The immobilized enzyme showed lower optimal temperature and a lower affinity for azocasein than the free enzyme purified from A. pullulans HN2-3. The thermal stability of the immobilized enzyme enhanced and the pH stability decreased, compared to that of the free enzyme.
从出芽短梗霉HN2-3中克隆得到的编码碱性蛋白酶的ALP2基因被连接到表面展示质粒中，并在解脂耶氏酵母细胞中表达。表达的碱性蛋白酶被固定在酵母细胞上。发现带有6×His标签的固定化酶的活性显著高于不带6×His标签的固定化酶。与从出芽短梗霉HN2-3中纯化的游离酶相比，固定化酶的最适温度较低，对偶氮酪蛋白的亲和力也较低。与游离酶相比，固定化酶的热稳定性增强，pH稳定性降低。
