摘要
利用酿酒酵母(Saccharomyces cerevisiae)表面展示系统,将来源于热带假丝酵母(Candida tropicalis)的木糖还原酶基因xyl1嵌入带有His-Tag的酿酒酵母α-凝集素展示载体pICAS-His,构建重组质粒pICAS- His-Ctxyl1,并转化到酿酒酵母宿主菌酿酒酵母MT8—1,通过流式细胞仪快速检测和筛选,得到重组菌株MT8- 1/pICAS-His—Ctxyl1。将重组酵母用于葡萄糖(15g/L)和木糖(5g/L)的混合糖发酵研究,结果表明,重组酿酒酵母MT8/1/pICAS-His—Ctxyl1细胞具有良好的生长和产酶特性,同时能转化木糖生产木糖醇,在培养基中2.5g/ L木糖转化生成2.5g/L木糖醇,转化率达98.7%。
A cell surface display system of Saccharomyces cerevisiae based on α-agglutinin was used to construct a recombinant plasmid pICAS-His-Ctxyll, inserting xylose reductase(XR) gene(xyl1) from C. tropicalis into an α-agglutinin expressive vector pICAS-His with His-Tag. The recombinant plasmid was transformed into S. cerevisiae MT8-1. The examination of immunofluorescence for His-Tag indicated that XR was displayed on the yeast cell wall. A recombinant S. cerevisiae was selected, named MT8-1/pICAS- His-Ctxyl1. Moreover, the recombinant S. cerevisiae MT8-1/pICAS-His-Ctxyl1 was cultivated in the medium containing glucose (15g/L) and xylose (Sg/L). It showed that cells grown lustily and displayed xylose reductase on surface actively, which invered xylose (2.5g/L) into xylitol effectively, with a conversion rate of 98.7%.
出处
《食品与发酵工业》
CAS
CSCD
北大核心
2008年第5期29-34,共6页
Food and Fermentation Industries
基金
广东省自然科学基金资助(No.04020051和06300199)