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In the present study,we reported the assembly of functional cellulolytic enzymes using a synthetic,cell-surface engineered yeast consortium.Trichoderma reesei endoglucanase II(EGII)and cellobiohydrolase II(CBHII)and Aspergillus aculeatus β-glucosidase I(BGLI)were displayed as fusion proteins with the AGA2p C-terminus of a-agglutinin on the cell surface of the diploid yeast strain Saccharomyces.cerevisiae Y5.The immobilization of each enzyme on the cell surface was confirmed by immunofluorescence microscopy.This type of yeast consortium allowed convenient optimization of ethanol production by adjusting the combination ratios of each cell type for inducing synergy in cellulose hydrolysis.Next,the direct ethanol fermentation from steam-exploded corn stover was investigated.The optimized cellulase-displaying consortium produced 20.4 g/l ethanol from 48.4g cellulose per liter after 72h in the presence of a small amount of cellulase reagent(0.9 FPU/ml).These findings suggested the feasibility of the cellulase-displaying yeast consortium for simultaneous saccharification and fermentation.