文献类型：期刊文献

英文题名：Expression and characterization of a novel cold-adapted chitosanase suitable for chitooligosaccharides controllable preparation

作者：Qin, Zhen[1,2];Chen, Qiming[1,2];Lin, Si[1];Luo, Sa[1];Qiu, Yongjun[1,2];Zhao, Liming[1,2]

机构：[1]East China Univ Sci & Technol, Sch Biotechnol, R&D Ctr Separat & Extract Technol Fermentat Ind, State Key Lab Bioreactor Engn, Shanghai 200237, Peoples R China;[2]Shanghai Collaborat Innovat Ctr Biomfg Technol, Shanghai 200237, Peoples R China

年份：2018

卷号：253

起止页码：139

外文期刊名：FOOD CHEMISTRY

收录：;EI(收录号：20180704788256);WOS:【SCI-EXPANDED(收录号:WOS:000426649300019)】；

基金：This work was financially supported by the National Natural Science Foundation of China (31701537), China Postdoctoral Science Foundation (2016M601530), Shanghai Sailing Program (17YF1403500), Fundamental Research Funds for the Central Universities (222201717026, 222201814031), and "Shu Guang" project of Shanghai Municipal Education Commission and Shanghai Education Development Foundation (15SG28). We wish to thank Long Dragon Bio Co. Limited, Huizhou, China to provide the standard chitooligosaccharides substrate.

语种：英文

外文关键词：Chitosanase; Chitooligosaccharide; Gynuella sunshinyii; Chitin conversion; Cold-adapted; Glycoside hydrolase family 46

摘要：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 degrees 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 degrees C; method for stopping the reaction: 50 degrees 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.