单酶法合成低分子量右旋糖酐的研究进展

Research Progress in the Synthesis of Low Molecular Weights Dextran by Single-Enzyme Method

关键词:  单酶法  右旋糖酐蔗糖酶  低分子量右旋糖酐  一步法

Key words:  single-enzyme method  dextransucrase  low molecular weight dextran  one-step method

摘要:

低分子量右旋糖酐(Dextran)是以蔗糖为底物，由右旋糖酐蔗糖酶(Dextransucrase,DSR)催化合成葡萄糖聚合物后，再经酸水解/酶水解形成的化合物，其分子量为10 000-20 000 Da，可广泛应用于医药、食品等行业。本文综述了单酶法合成右旋糖酐的研究进展，包括微生物法/酶法生产右旋糖酐的优缺点，DSR的高效表达，单酶法合成右旋糖酐的过程调控，DSR的固定化技术、结构和催化机理，以及单酶法合成低分子量右旋糖酐的研究现状，并在此基础上提出DSR单酶一步法直接合成低分子量右旋糖酐的思路。借助人工智能技术可获得更详细的DSR结构信息，在进一步解析DSR的结构、功能和催化机理的基础上，对其进行合理的设计和改进，优化酶学性质，实现单酶一步法直接合成低分子量右旋糖酐，可为生产低分子量右旋糖酐提供了新的理论支持。

Abstract:

Low molecular weight dextran is synthesized by acid hydrolysis/enzymatic hydrolysis of glucose polymers catalyzed by Dextransucrase (DSR) using sucrose as a substrate.The molecular weight is 10 000-20 000 Da,which is widely used in medicine,food and other industries.In this article,the research progress on single enzyme synthesis of dextran were reviewed,including the advantages and disadvantages of microbial/enzymatic production of dextran,the efficient expression of DSR,the process regulation of single enzyme synthesis of dextran,the immobilization technology,the structure and catalytic mechanism of DSR,as well as the current research status of single enzyme synthesis of low molecular weight dextran.Based on this,the idea of DSR single enzyme one-step synthesis of low molecular weight glucan is proposed.With the help of artificial intelligence technology,more detailed DSR structure information is obtained.On the basis of further analyzing the structure,function and catalytic mechanism of DSR,it is designed and improved reasonably,and the enzymatic properties are optimized to realize the direct synthesis of low molecular weight dextran by single enzyme one-step method,which provides new theoretical support for the production of low molecular weight dextran.