Author:
Jiang Chengcheng,Secundo Francesco,Mao Xiangzhao
Abstract
AbstractCarrageenan oligosaccharides are important products that have demonstrated numerous bioactivities useful in the food, medicine, and cosmetics industries. However, the specific structure–function relationships of carrageenan oligosaccharides are not clearly described due to the deficiency of high specific carrageenases. Here, a truncated mutant OUC-FaKC16Q based on the reportedκ-neocarratetrose (Nκ4)-producingκ-carrageenase OUC-FaKC16A fromFlavobacterium algicolawas constructed and further studied. After truncating the C-terminal Por_Secre_tail (PorS) domain (responsible for substrate binding), the catalytic efficiency and temperature stability decreased to a certain extent. Surprisingly, this truncation also enabled OUC-FaKC16Q to hydrolyze Nκ4 intoκ-neocarrabiose (Nκ2). The offset of Arg265residue in OUC-FaKC16Q may explain this change. Moreover, the high catalytic abilities, the main products, and the degradation modes of OUC-FaKC16A and OUC-FaKC16Q toward furcellaran were also demonstrated. Data suggested OUC-FaKC16A and OUC-FaKC16Q could hydrolyze furcellaran to produce mainly the desulfated oligosaccharides DA-G-(DA-G4S)2and DA-G-DA-G4S, respectively. As a result, the spectrum of products ofκ-carrageenase OUC-FaKC16A has been fully expanded in this study, indicating its promising potential for application in the biomanufacturing of carrageenan oligosaccharides with specific structures.
Publisher
Springer Science and Business Media LLC
Subject
Aquatic Science,Ecology, Evolution, Behavior and Systematics,Oceanography,Biotechnology