表达和鉴定一种适合于可控制备壳寡糖的新型耐冷壳聚糖酶。

Expression and characterization of a novel cold-adapted chitosanase suitable for chitooligosaccharides controllable preparation.

机构信息

School of Biotechnology, State Key Laboratory of Bioreactor Engineering, R&D Center of Separation and Extraction Technology in Fermentation Industry, East China University of Science and Technology, Shanghai 200237, China; Shanghai Collaborative Innovation Center for Biomanufacturing Technology (SCICBT), Shanghai 200237, China.

出版信息

Food Chem. 2018 Jul 1;253:139-147. doi: 10.1016/j.foodchem.2018.01.137. Epub 2018 Jan 31.

DOI:10.1016/j.foodchem.2018.01.137

PMID:29502814

Abstract

Chitooligosaccharide is widely used as a functional food additive and a valuable pharmacological agent. The transformation of chitinous biomass into valuable bioactive chitooligosaccharides is one of the most exciting applications of chitosanase. A novel glycoside hydrolase (GH) family 46 chitosanase (GsCsn46A) from rhizobacterium Gynuella sunshinyii was cloned and heterologously expressed in Escherichia coli. GsCsn46A showed maximal activity at pH 5.5 and 30 °C. GsCsn46A featured remarkable cold-adapted property, which controllably hydrolyzed chitosan to three types of chitooligosaccharides at the mild reaction condition (reaction condition: pH 5.5 at 30 °C; method for stopping the reaction: 50 °C for 30 min). The yields of three types of chitooligosaccharides products (degree of polymerization (DP): 2-7, 2-5 and 2-3) were 70.9%, 87.1% and 94.6% respectively. This novel cold-adapted chitosanase provides a cleaner production process for the controllable preparation of chitooligosaccharides with the specific DP.

摘要

壳寡糖被广泛用作功能性食品添加剂和有价值的药理学制剂。将甲壳素生物质转化为有价值的生物活性壳寡糖是壳聚糖酶最令人兴奋的应用之一。从根际细菌粘帚霉中克隆并异源表达了一种新型糖苷水解酶（GH）家族 46 壳聚糖酶（GsCsn46A）。GsCsn46A 在 pH5.5 和 30°C 时表现出最大活性。GsCsn46A 具有显著的耐冷特性，可在温和的反应条件下（反应条件：pH5.5，30°C；停止反应的方法：50°C，30min）将壳聚糖可控水解成三种类型的壳寡糖。三种类型的壳寡糖产物（聚合度（DP）：2-7、2-5 和 2-3）的产率分别为 70.9%、87.1%和 94.6%。这种新型耐冷壳聚糖酶为具有特定 DP 的壳寡糖的可控制备提供了更清洁的生产工艺。