酵母菌木糖转运蛋白研究进展

利用工农业废料生产的纤维素乙醇属于第二代燃料乙醇，原料来源广泛、价格便宜，具有不与粮争地、不与人争粮的特点，受到国内外的广泛关注。纤维素乙醇工业化生产的关键在于木糖的利用，但是目前构建的能够利用木糖的基因工程菌株存在木糖发酵速度慢或乙醇得率低的缺点，其中最重要的原因之一是木糖由胞外到胞内的转运受到限制，这就涉及到糖转运蛋白在木糖发酵中的重要作用。现就近年来关于木糖转运蛋白的研究进行综述及讨论。

Research Progress on Xylose Transporters in Yeast

Cellulosic ethanol produced by biological fermentation of agricultural and industrial residues,which has wide resources with low price,is regarded as the second generation fuel-ethanol.lignocellulosic fuel-ethanol is receiving more and more attention,owing to the fact that it does not compete for land with crops,neither for grain with human beings.Xylose is the major building blocks of hemicellulose,so its utilization is the bottleneck for realizing economical and feasible production of bio-ethanol from lignocellulose.Considerable effort has been made to introduce pentose-metabolizing pathways into Saccharomyces cerevisiae,and to optimize the native pentose phosphate pathway.But the rates of xylose consumption by such engineered strains and the ethanol yield are still lower than glucose.One of the most important reasons is the limitation of xylose from extracellular to intracellular.In other words,we have to discuss the importance of sugar transporters in xylose fermentation.In recent years,the importance of xylose transporters has been revealed,and big progress has been made.In this article,the current research on xylose transporters were reviewed and discussed.