基于木糖异构酶途径的木糖发酵酿酒酵母菌株构建研究进展  

Research Progresses on Strain Construction of Xylose Isomerase-based Recombinant Xylose-fermenting Saccharomyces cerevisiae

作　　者：李云成 孟凡冰 苟敏[2] 孙照勇[2] 汤岳琴[2] 

机构地区：[1]成都大学药学与生物工程学院,成都610106 [2]四川大学建筑与环境学院,成都610207

出　　处：《生物技术通报》2017年第10期88-96,共9页Biotechnology Bulletin

基　　金：四川省科技创新苗子工程重点项目(2017RZ0021);成都大学校青年基金项目(2017XJZ18)

摘　　要：通过异源表达木糖代谢途径,构建能高效发酵木糖产乙醇的工业酿酒酵母菌株,对木质纤维素燃料乙醇的开发具有重要意义。与氧化还原途径相比,木糖异构化途径的表达不会因辅酶不平衡而造成中间产物木糖醇的累积,因此被视为是理想的木糖代谢途径。在木糖异构途径的表达过程中,选择工业酿酒酵母作为出发菌株进行木糖异构酶途径的表达具有突出优势。同时,提高木糖异构酶基因xyl A的表达效率对木糖异构菌株的构建至关重要。另外,在对XI菌株进行代谢工程改造时,GRE3的敲除、木糖转运的提升、木糖代谢途径的定向改造等均能有效改善菌株发酵木糖产乙醇的能力。除此之外,进化工程也是提升XI菌株木糖发酵效率的重要方法之一。而在相关机理阐释和改造策略的制定过程中,组学技术已显示出强大的功能。综述了近年来木糖异构酶途径在酿酒酵母中的表达研究进展,同时还对相关研究存在的问题进行了分析。It is of utmost significant to construct industrial xylose-fermenting Saccharomyces cerevisiae strains for lignocellulosicbioethanol production through the heterologous expression of xylose metabolic pathway. Xylose isomerase pathway is regarded as the mostpromising pathway expressing in S. cerevisiae,since there is no xylitol accumulation resulted from the coenzyme imbalance in xylose redoxpathway. In heterologous expression of xylose isomerase,selecting an industrial S. cerevisiae strain as initial strain is of outstanding advantagesfor lignocellulosic bioethanol production. Concurrently,improving the expression efficiency of xylose isomerase gene（xyl A）is vital forconstructing a robust xylose fermentation strain. In addition,the deletion of GRE3,strengthening of xylose transport and rational modificationof xylose metabolic pathway during the metabolic modification of strain XI effectively improved the xylose fermentation capacity of therecombinant strains. Besides,evolutionary engineering also increased the xylose fermentation efficiency of XI strains. Furthermore,the omicstechnologies have presented their power in explaining the mechanism and developing the modification strategies of xylose metabolism. This paperreviews the research progresses on the expressions of xylose isomerase pathway in S. cerevisiae and analyzes the issues in the relevant studies.

关 键 词：酿酒酵母 燃料乙醇 木糖异构酶 菌株构建 

分 类 号：Q78[生物学—分子生物学] Q93