毕赤酵母表面展示麦芽三糖生成酶全细胞催化制备麦芽三糖  

Cell-Surface Display of Maltotriose-Producing α-Amylase in Pichia Pastoris and Preparation of Maltotriose from Whole-Cell Catalyst

作　　者：钱玲 郑一文 林影[1] 郑穗平[1] QIAN Ling;ZHENG Yiwen;LIN Ying;ZHENG Suiping(Guangdong Key Laboratory of Fermentation and Enzyme Engineering,Guangdong Research Center of Industrial Enzyme and Green Manufacturing Technology,School of Bioscience and Bioengineering,South China University of Technology,Guangzhou 510006,China)

机构地区：[1]华南理工大学生物科学与工程学院,广东省发酵与酶工程重点实验室,广东省生物酶与工业绿色加工工程技术研究中心,广东广州510006

出　　处：《食品科技》2020年第5期1-7,共7页Food Science and Technology

基　　金：国家重点研发专项(2018YFA0901700);国家自然科学基金项目(31671840)。

摘　　要：通过表面展示技术,得到一种不需纯化、能多次重复利用且成本较低的全细胞催化剂,用于制备麦芽三糖。以毕赤酵母细胞GPI型壁蛋白Gcw61p作为锚定蛋白,将Thermobifida fusca NTU22来源的麦芽三糖生成酶表面展示在巴斯德毕赤酵母细胞壁上,发酵冻干制成全细胞催化剂,测定酶活并分析其酶学性质及重复利用性。结果表明,表面展示菌株生长情况正常,酶活为260 U/g;最适温度为55℃,55℃保温1 h仍有95%残余酶活;最适pH为6.0;全细胞催化剂在重复利用3次的条件下,残余酶活还剩80%。在此基础上探究了全细胞催化剂用于制备麦芽三糖,结果表明,当底物为30%麦芽糊精时,糊精转化率为60.13%,麦芽三糖占比50.24%。研究结果为麦芽三糖的制备提供了一种思路。A whole-cell catalyst for preparing maltotriose was obtained via cell-surface display technology,and it has attractive advantages of lower cost,continuous utilization and even without protein purification.In this study,maltotriose-producingα-amylase from Thermobifida fusca NTU22 was displayed on the cell wall of Pichia pastoris with the anchor protein gene Gcw61p from P.pastoris GPI-type wall protein.Whole-cell catalyst was prepared by fermentation and lyophilization to character its enzymatic properties and reusability.The results showed that the growth of the surface display strain was identical with wild type.The enzyme activity was 260 U/g.Furthermore,the optimal temperature for enzymatic activity was 55℃,and 95%residual enzyme activity remained at 55℃for 1 h.The optimal pH was 6.0.And the enzyme activity remained at 80%after being reused 3 cycles.Subsequently,the effect of whole-cell catalyst on producing maltotriose was explored.The results showed that when the substrate was 30%maltodextrin,it achieved 60.13%conversion rate of dextrin,and maltotriose accounted for 50.24%.The research provided an idea for the preparation of maltotriose.

关 键 词：毕赤酵母 表面展示 全细胞催化剂 麦芽三糖生成酶 麦芽三糖 

分 类 号：TS201.3[轻工技术与工程—食品科学]