Enhanced surface display efficiency of β-glucosidase in Saccharomyces cerevisiae by disruption of cell wall protein-encoding genes YGP1 and CWP2

Engineering of Saccharomyces cerevisiae for being capable of displaying a sufficient amount of cellulases on their cell surface needs to be accomplished for the development of an ideal microorganism for cellulosic ethanol production. This study aimed to explore the effects of two cell wall protein genes, CWP2 and YGP1, on β-glucosidase (BGL) activity on the yeast cell surface. The results showed that the disruption of YGP1 and CWP2 increased BGL activity by 63% and 24%, respectively, compared to that of the original strain. Moreover, the YGP1 disruptant produced 59% more ethanol from cellobiose than the parent strain. Further transcriptome analysis of the YGP1 disruptant strain revealed changes in the expression of genes involved in cell wall structure, biogenesis, and integrity, which might contribute to the elevated BGL display efficiency. This study provides an alternative engineering approach for enhancing the cell surface display of heterologous proteins on the yeast cell wall.