海洋科学2025，Vol.49Issue(6)：15-24,10.DOI:10.11759/hykx20250225003
海带(Saccharina japonica)甘露糖醛酸C5异构酶的功能分析
Functional analysis of mannuronan C5-epimerases from Saccharina japonica
摘要
Abstract
Alginate,a linear polymer of β-D-mannuronic acid(M)and its C5 epimer α-L-guluronic acid(G),serves as a crucial carbon metabolite for the brown alga Saccharina japonica.Alginate is widely used in industries such as food,medicine,textiles,and agriculture.Mannuronan C5-epimerase(MC5E)is a critical enzyme of the alginate biosynthesis pathway that catalyzes the epimerization of M to G.This study identified a highly expressed SjMC5E3 sequence from the genome of S.japonica and isolated it.It was used to transform Escherichia coli for in vitro ex-pression.The protein synthesized was purified.Enzyme assays utilizing Proton Nuclear Magnetic Resonance Spec-troscopy demonstrated an M/G ratio of 4.63 in the SjMC5E3-catalyzed reaction products,confirming its capability to convert M residues in alginate to G residues.Thus,this study reveals the vital role of MC5E in the alginate bio-synthesis pathway,which is of great relevance for the production of alginate with a high G content,and can provide technical support for the industrial-scale preparation of alginate products in the future.关键词
海带/甘露糖醛酸C5异构酶/褐藻胶Key words
Saccharina japonica/mannuronan C5-epimerase/alginate分类
生物科学引用本文复制引用
孟雪,李爽,张杰,段德麟..海带(Saccharina japonica)甘露糖醛酸C5异构酶的功能分析[J].海洋科学,2025,49(6):15-24,10.基金项目
外交部中国-印尼海洋牧场建设与示范项目(2020WJB06) （2020WJB06）
青岛国际合作项目(22-3-6-ghgg-1-hz)The China-Indonesia Marine Ranch Construction and Demon-stration Project of the Ministry of Foreign Affairs of China,No.2020WJB06 （22-3-6-ghgg-1-hz）
Qingdao International Collaboration Project,No.22-3-6-ghgg-1-hz （）
