O-19 統合型バイオエタノール生産プロセスの構築に資する改良型酵母細胞表層提示用遺伝子カセットの開発

抄録

The recombinant yeast strains displaying the heterologous cellulolytic enzymes on the cell surface using the glycosylphosphatidylinositol (GPI) anchoring system are considered promising biocatalysts for the consolidated bioethanol production from lignocellulosic biomass. In this study, we constructed novel gene cassettes for the efficient cellulase display on yeast cell surface. We revealed that simultaneous utilization of the GPI anchoring region derived from Saccharomyces cerevisiae SED1 and its original promoter in a gene cassette enabled highly-efficient enzyme integration into the cell wall. The β-glucosidase and endoglucanase activities of recombinant yeast cells transduced with the novel gene cassette were 8.4- and 106-fold higher than those of conventional strains. The novel gene cassette also improved cell-surface hemicellulase activity. These results suggest that the novel gene cassette has the wide applicability for efficient cell-surface display of heterologous enzymes and that recombinant yeast cells displaying enzymes using these cassettes are promising biocatalysts for the efficient ethanol production from biomass resources.