【摘要】 基于絮凝素FLO1基因片段为锚定序列,构建以诱导型GAL1启动子介导的表达载体YEP-GMPFAK,并实现以半乳糖为诱导剂,β-1,3-1,4-葡聚糖酶在酿酒酵母表面的展示表达。酵母转化子发酵实验表明,在pH6.0、50℃培养条件下,经2%半乳糖诱导24 h,表面展示酶活达到最大值322.83 U/g细胞干重。酶学性质测定表明,展示表达的β-1,3-1,4-葡聚糖酶具有良好的热稳定性。更多还原

【Abstract】 A yeast surface-display expression vector YEP-GMPFAK mediated by inducible GAL1 promoter and based on flocculation(FLO1) gene fragment as an anchor was constructed.When industry Saccharomyces cerevisiae was transformed using this vector and then induced by galactose,β-1,3-1,4-glucanase was expressed on yeast surface.Fermentation experiment showed that the β-1,3-1,4-glucanas activity displayed on yeast surface reached 322.83 U/(g·dry cell weight) at the cultivating condition of 50 ℃、 pH 6.0,after adding 2% galactose for 24 h.The dectection results of enzymatic properties showed that the surface-displayed β-1,3-1,4-glucanase also exhibited favorable thermal stability.更多还原