One of the requirements for increasing the economic profitability on the large-scale production of second-generation ethanol and other bio-chemicals using lignocellulose biomass as raw materials is efficient hexose and pentose utilization. Saccharomyces cerevisiae, the traditional ethanol producer, is an attractive chassis cell due to its robustness towards harsh environmental conditions and inherent advantages. But S. cerevisiae cannot utilize pentose. The precision construction of suitable strains for second-generation bio-ethanol production has been taken for more than three decades based on the principle of metabolic engineering and synthetic biology. The resulting strains have improved significantly co-fermentation of glucose and xylose. Recently, much attentions have been focused on sugar transport, which is one of the limiting but formerly ignored step for ethanol production from both glucose and xylose, to get the desired state that different sugars could efficiently delivered by their individual specific transporters. In this paper, the progress on sugar transporters of S. cerevisiae was reviewed, and the research status of xylose and/or L-arabinose metabolic engineering in S. cerevisiae were also presented.
充分利用木质纤维素中的糖分是提高以此类生物质为原料生产二代燃料乙醇经济盈利性的基本要求，也是实现其他生物基化学品规模化生产的基础。传统的乙醇生产微生物酿酒酵母Saccharomyces cerevisiae 具有独特的生产性能及内在优势，是备受关注的底盘细胞，但其不能有效地利用戊糖。利用代谢工程、合成生物学策略，对二代燃料乙醇生产专用酿酒酵母的精准构制持续研究了30 余年，已明显改善了其对木糖/葡萄糖的乙醇共发酵能力。近年来关注点集中在早期忽略的限速步骤即糖转运环节的研究上，以期实现不同糖分各行其道、高效专一性转运蛋白各行其责的二代燃料乙醇生产特种酿酒酵母所需的糖转运理想状态。文中主要综述了酿酒酵母戊糖转运蛋白的研究进展，及酿酒酵母的木糖和L-阿拉伯糖代谢工程的研究现状。.
Keywords: budding yeast; lignocellulosic bioethanol; metabolic engineering; pentose; sugar transporter.