纤维素酶细胞表面展示酵母菌群的构建及纤维素乙醇的发酵优化研究  

CONSTRUCTION OF CELL SURFACE ENGINEERED Saccharomyces cerevisiae CONSORTIUM SYSTEMS AND OPTIMIZATION OF CELLULOSE ETHANOL PRODUCTION

作　　者：杨非[1] 金怡[1] 莫春玲[1] 杨秀山[1] 田沈[1] 

机构地区：[1]首都师范大学生命科学学院,北京100048

出　　处：《太阳能学报》2015年第3期696-702,共7页Acta Energiae Solaris Sinica

基　　金：国家自然科学基金(31100578);国家科技支撑计划课题(2013BAD22B03);北京市教育委员会科技计划重点项目(KZ201310028034)

摘　　要：利用酵母细胞表面展示技术,以酿酒酵母菌株Saccharomyces cerevisiae Y5为受体,通过a-凝集素锚定方式,将来自丝状真菌Trichoderma reesei的内切葡聚糖酶II(EGII)、纤维二糖水解酶II(CBHII)以及来自Aspergillus aculeatus的β-葡糖苷酶I(BGLI)展示在细胞表面,构建同时表达3种纤维素酶的酵母菌群系统。结果表明,固定展示在细胞表面的纤维素酶在发酵过程中可保持较好的酶活性和稳定性;同时在EGII、CBHII和BGLI协同作用下使酵母细胞能水解纤维素并产生乙醇。将重组菌株Y5/EGII、Y5/CBHII和Y5/BGLI按1∶1∶1、1∶2∶1和2∶1∶1组合为不同的实验组,发酵结果显示,组合比为2∶1∶1的实验组效果最佳,最高乙醇浓度达到0.76 g/L,乙醇产量为0.33 g/g,相当于理论值的64.9%。A yeast consortium was constructed by yeast surface engineering technology which endoglucanase Ⅱ （EGII） and cellobiohydrolase Ⅱ （CBHII） from Trichoderma reesei and β- glucosidase 1 （BGLI） from Aspergillus aculeatus were displayed on Saccharomyces cerevisiae Y5 as the fusion protein with the C terminal region of a-agglutinin. The results showed that the displayed cellulolytic enzymes showed stability activities during the fermentation. Simultaneously expressed of EGII, CBHII and BGLI gave yeast cells the ability to break down and ferment amorphous cellulose to ethanol. The optimized consortia consisted of three stains Y5/EGII, Y5/CBHII, Y5/ BGLI ratio of 1 ： 1 ： 1,1 ： 2 ： 1, and 2 ： 1 ： 1, respectively. The ratio at 2 ： 1 ： 1 of consortium produced the highest ethanol which was 0.76 g/L, the yield（in grams of ethanol produced per gram of carbohydrate consumed）was 0.33 g/g, which correspond to 64.9% of the theoretical yield.

关 键 词：酵母表面工程 a-凝集素 菌群优化 纤维素乙醇 

分 类 号：TK6[动力工程及工程热物理—生物能]