工业黑曲霉菌株O1中多种酶对淀粉糖化的协同作用。

Synergistic effects of multiple enzymes from industrial Aspergillus niger strain O1 on starch saccharification.

作者信息

Guo Wenzhu, Yang Jianhua, Huang Tianchen, Liu Dandan, Liu Qian, Li Jingen, Sun Wenliang, Wang Xingji, Zhu Leilei, Tian Chaoguang

机构信息

Key Laboratory of Systems Microbial Biotechnology, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308, China.

National Technology Innovation Center of Synthetic Biology, Tianjin, 300308, China.

出版信息

Biotechnol Biofuels. 2021 Nov 27;14(1):225. doi: 10.1186/s13068-021-02074-x.

DOI:10.1186/s13068-021-02074-x

PMID:34838099

原文链接:https://pmc.ncbi.nlm.nih.gov/articles/PMC8627030/

Abstract

BACKGROUND

Starch is one of the most important renewable polysaccharides in nature for production of bio-ethanol. The starch saccharification step facilitates the depolymerization of starch to yield glucose for biofuels production. The filamentous fungus Aspergillus niger (A. niger) is the most used microbial cell factory for production of the commercial glucoamylase. However, the role of each component in glucoamylases cocktail of A. niger O1 for starch saccharification remains unclear except glucoamylase.

RESULTS

In this study, we identified the key enzymes contributing to the starch saccharification process are glucoamylase, α-amylase and acid α-amylase out of 29 glycoside hydrolases from the 6-day fermentation products of A. niger O1. Through the synergistic study of the multienzymes for the starch saccharification in vitro, we found that increasing the amount of α-amylase by 5-10 times enhanced the efficiency of starch saccharification by 14.2-23.2%. Overexpression of acid α-amylase in strain O1 in vivo increased the total glucoamylase activity of O1 cultures by 15.0%.

CONCLUSIONS

Our study clarifies the synergistic effects among the components of glucoamylases cocktail, and provides an effective approach to optimize the profile of saccharifying enzymes of strain O1 for improving the total glucoamylase activity.

摘要

背景

淀粉是自然界中用于生产生物乙醇的最重要的可再生多糖之一。淀粉糖化步骤有助于淀粉解聚以产生用于生物燃料生产的葡萄糖。丝状真菌黑曲霉是生产商业糖化酶最常用的微生物细胞工厂。然而，除糖化酶外，黑曲霉O1糖化酶混合物中各组分在淀粉糖化中的作用仍不清楚。

结果

在本研究中，我们从黑曲霉O1 6天发酵产物的29种糖苷水解酶中鉴定出对淀粉糖化过程有贡献的关键酶为糖化酶、α-淀粉酶和酸性α-淀粉酶。通过对多酶体外淀粉糖化的协同研究，我们发现将α-淀粉酶的量增加5-10倍可使淀粉糖化效率提高14.2-23.2%。体内在菌株O1中过表达酸性α-淀粉酶使O1培养物的总糖化酶活性提高了15.0%。