Liu Han, Wang Xuxin, Liu Yanping, Kang Zhuoran, Lu Jiaqi, Ye Yutong, Wang Zhipeng, Zhuang Xinshu, Tian Shen
College of Life Science, Capital Normal University, Beijing, 100048, China.
Department of Environmental Science and Engineering, Beijing University of Chemical Technology, Beijing, 100029, China.
Bioresour Bioprocess. 2022 Sep 19;9(1):101. doi: 10.1186/s40643-022-00585-5.
The enhanced hydrolysis of xylan-type hemicellulose is important to maximize ethanol production yield and substrate utilization rate in lignocellulose-based simultaneous saccharification and co-fermentation system. In this study, we conduct δ-integration CRISPR Cas9 to achieve multicopy chromosomal integration with high efficiency of reductase–xylitol dehydrogenase pathway in . Subsequently, we devise a consolidated bioprocessing-enabling consortium, in which every engineered yeast strain could secrete or display different assembly components to be adaptively assembled on the surface of scaffoldin-displaying yeast cell for synergistic catalysis and co-fermentation from steam-exploded . Despite the accumulation of xylitol, the maximum ethanol titer of the genetically engineered yeast strain reached 12.88 g/l with the cellulose conversion of 91.21% and hemicellulose conversion of 55.25% under 30 ºC after 96 h with the addition of commercial cellulase. The elaborated cellulosomal organization toward genetic engineering of an industrially important microorganism presents a designed approach for advanced lignocellulolytic potential and improved capability of biofuel processing.
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The online version contains supplementary material available at 10.1186/s40643-022-00585-5.
在基于木质纤维素的同步糖化和共发酵系统中，提高木聚糖型半纤维素的水解对于最大化乙醇产量和底物利用率至关重要。在本研究中，我们进行了δ整合CRISPR Cas9，以在中高效实现还原酶-木糖醇脱氢酶途径的多拷贝染色体整合。随后，我们设计了一个支持整合生物加工的联合体，其中每个工程酵母菌株都可以分泌或展示不同的组装组件，以便在展示支架蛋白的酵母细胞表面进行适应性组装，从而对蒸汽爆破后的进行协同催化和共发酵。尽管木糖醇有所积累，但在添加商业纤维素酶的情况下，经过96小时，在30℃条件下，基因工程酵母菌株的最大乙醇滴度达到12.88 g/l，纤维素转化率为91.21%，半纤维素转化率为55.25%。针对工业重要微生物的基因工程精心构建的纤维小体组织为提高木质纤维素分解潜力和改善生物燃料加工能力提供了一种设计方法。
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在线版本包含可在10.1186/s40643-022-00585-5获取的补充材料。
