Kim June-Hyung, Park In-Suk, Kim Byung-Gee
Institute for Molecular Biology and Genetics, School of Chemical Engineering, Seoul National University, Seoul, Republic of Korea.
Biochem Biophys Res Commun. 2005 Sep 9;334(4):1248-53. doi: 10.1016/j.bbrc.2005.07.024.
We report a new membrane surface display system based on molecular chaperon, prsA, of Bacillus subtilis. Clostridium thermocellum cellulase, celA, was fused to C-terminal end of PrsA. Cellulase activity of B. subtilis protoplast, which expressed PrsA-CelA was 15 times higher compared to control strain. More than 85% of total cellulase activity was observed in surface displayed format and less than 15% of total cellulase activity was found in supernatant. Flow cytometric analysis of protoplast of PrsA-CelA fusion expressing bacteria provided another proof of uniform expression of fusion protein onto cytoplasmic membrane of B. subtilis. Without lysozyme treatment, only part of cellulase activity (10%) was observed in whole cell fraction.
我们报道了一种基于枯草芽孢杆菌分子伴侣PrsA的新型膜表面展示系统。热纤梭菌纤维素酶CelA与PrsA的C末端融合。表达PrsA-CelA的枯草芽孢杆菌原生质体的纤维素酶活性比对照菌株高15倍。超过85%的总纤维素酶活性以表面展示形式存在，而在上清液中发现的总纤维素酶活性不到15%。对表达PrsA-CelA融合蛋白的细菌原生质体进行流式细胞术分析，进一步证明了融合蛋白在枯草芽孢杆菌细胞质膜上的均匀表达。未经溶菌酶处理时，在全细胞部分仅观察到部分纤维素酶活性（10%）。
