Liu Wenshan, Xu Li, Zhao Heyun, Yang Jiangke, Yan Yunjun
College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan 430074, China.
Wei Sheng Wu Xue Bao. 2008 Nov;48(11):1543-8.
In order to display extracellular.lipase Lip2 from Yarrowia lipolytica on the surface of yeast Saccharomyces cerevisiae for whole cell catalysts.
The mature Lip2 encoding fragment was amplified from Yarrowia lipolytica total DNA, and was inserted into the 3'terminal of AGA2 to give the plasmid pCTLIP2 for surface display of Lip2. Olive oil, tributyrin and p-nitrophenyl palmitate (pNPP) were used as substrates to measure lipase activity. Moreover, the characterization of displayed lipase and its free form was analyzed.
The surface displayed lipase was confirmed to be active towards olive oil, tributyrin and p-nitrophenyl palmitate (pNPP), and reached its highest expression level at 182 U/g dry cell after induced by galactose for 72h. The optimum temperature of cell surface displayed Lip2 was 40 degrees C After incubated at 50 degrees C for 4h, the surface displayed lipase retained 23.2% of its full activity, improved a little compared to free Lip2. The surface displayed lipase showed a preference to medium-chain and long-chain fatty acids p-nitrophenyl esters (C8-C16).
The cell surface display system based on a-agglutinin is an effective system for displaying Lip2, and the whole cell EBY100-pCTLIP2 will be probably suited to a different range of applications.
为了将解脂耶氏酵母的胞外脂肪酶Lip2展示在酿酒酵母表面,以构建全细胞催化剂。
从解脂耶氏酵母总DNA中扩增出成熟的Lip2编码片段,并将其插入AGA2的3'末端,构建用于Lip2表面展示的质粒pCTLIP2。以橄榄油、三丁酸甘油酯和对硝基苯基棕榈酸酯(pNPP)为底物测定脂肪酶活性。此外,还对展示型脂肪酶及其游离形式进行了特性分析。
证实表面展示的脂肪酶对橄榄油、三丁酸甘油酯和对硝基苯基棕榈酸酯(pNPP)具有活性,在半乳糖诱导72小时后,其表达水平达到最高,为182 U/g干细胞。细胞表面展示的Lip2的最适温度为40℃。在50℃孵育4小时后,表面展示的脂肪酶保留了其全部活性的23.2%,与游离Lip2相比略有提高。表面展示的脂肪酶对中链和长链脂肪酸对硝基苯基酯(C8-C16)表现出偏好。
基于α-凝集素的细胞表面展示系统是展示Lip2的有效系统,全细胞EBY100-pCTLIP2可能适用于不同的应用范围。