Department of Food Science and Human Nutrition, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA; Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA; Department of Bioengineering and Technology, Kangwon National University, Chuncheon, Republic of Korea.
Bioresour Technol. 2013 Dec;149:525-31. doi: 10.1016/j.biortech.2013.09.082. Epub 2013 Sep 27.
Simultaneous fermentation of cellobiose and xylose by an engineered Saccharomyces cerevisiae has been demonstrated in batch fermentation, suggesting the feasibility of continuous co-fermentation of cellulosic sugars. As industrial S. cerevisiae strains have known to possess higher ethanol productivity and robustness compared to laboratory S. cerevisiae strains, xylose and cellobiose metabolic pathways were introduced into a haploid strain derived from an industrial S. cerevisiae. The resulting strain (JX123-BTT) was able to ferment a mixture of cellobiose and xylose simultaneously in batch fermentation with a high ethanol yield (0.38 g/g) and productivity (2.00 g/L · h). Additionally, the JX123-BTT strain co-consumed glucose, cellobiose, and xylose under continuous culture conditions at a dilution rate of 0.05 h(-1) and produced ethanol resulting in 0.38 g/g of ethanol yield and 0.96 g/L · h of productivity. This is the first demonstration of co-fermentation of cellobiose and xylose by an engineered S. cerevisiae under continuous culture conditions.
已在分批发酵中证明了经工程改造的酿酒酵母同时发酵纤维二糖和木糖，这表明了纤维素糖连续共发酵的可行性。由于工业酿酒酵母菌株与实验室酿酒酵母菌株相比具有更高的乙醇生产率和鲁棒性，因此将木糖和纤维二糖代谢途径引入源自工业酿酒酵母的单倍体菌株中。所得菌株（JX123-BTT）能够在分批发酵中同时发酵纤维二糖和木糖混合物，乙醇得率（0.38 g/g）和生产率（2.00 g/L·h）均较高。此外，在 0.05 h(-1) 的稀释率下，JX123-BTT 菌株在连续培养条件下共消耗葡萄糖、纤维二糖和木糖，并产生乙醇，乙醇得率为 0.38 g/g，生产率为 0.96 g/L·h。这是在连续培养条件下经工程改造的酿酒酵母共发酵纤维二糖和木糖的首次证明。
