木糖异构酶在酿酒酵母表面表达及对木糖代谢影响的初步研究  

Expression xylose isomerase on Saccharomyces cerevisiae cell surface and its influence on xylose metabolism

作　　者：侯进[1] 沈煜[1] 鲍晓明[1] 

机构地区：[1]山东大学微生物技术国家重点实验室,济南250100

出　　处：《生物加工过程》2006年第1期30-34,共5页Chinese Journal of Bioprocess Engineering

基　　金：国家自然科学基金委员会资助项目(No:50273019)

摘　　要：利用α-型酿酒酵母(Saccharomyces cerevisiae)表面展示系统的载体,将来源于嗜热细菌Thermus thermophilus的木糖异构酶基因xylA,插入到酿酒酵母蔗糖酶信号肽序列与α-凝集素的C端编码序列之间,形成融合表达框,构建重组质粒pSY-xy222,转化酿酒酵母H158。含重组质粒的菌株H158-SXI木糖异构酶活性测定表明,细胞壁上酶活测定值为1.53 U,木糖异构酶在酿酒酵母细胞壁上得到活性表达。木糖葡萄糖共发酵结果显示,重组菌株木糖利用率较出发菌株提高了17.8%。The xylose isomerase gene xylA from Thermus thermophilus was fused with the sequence encoding the α-agglutinin C-terminal of Agαp and the signal peptide of S. cerevisiae invertase contained in the yeast α- agglutinin surface display vector pPGA1. The fused gene was under the control of PGK promoter. The recombinant plasmid was transformed into the yeast stain H158 by the lithium acetate method. The recombinant strain expressing the fusion protein was named H158-SXI. The XI activity detected on cell wall was 40.33 U/g dry weight. Glucose and xylose co-fermentation by H158-SXI consumed 4.8 g/L xylose,which is 17.8% higer than parent strain H158.

关 键 词：酵母表面展示 α-凝集素 木糖异构酶 酿酒酵母 

分 类 号：Q78[生物学—分子生物学]