Biochemical characterization and degradation pattern analysis of a novel PL-6 alginate lyase from Streptomyces coelicolor A3(2)

• Published in: Food chemistry 2020-09, Vol.323, p.126852-126852, Article 126852
• Main Authors: Cheng, Danyang, Liu, Zhen, Jiang, Chengcheng, Li, Laihao, Xue, Changhu, Mao, Xiangzhao
• Format: Article
• Language: English
• Subjects: Alginate lyase; Brown macroalgae; Modification; PL-6 family; Streptomyces coelicolor A3
• ISSN: 0308-8146; 1873-7072
• DOI: 10.1016/j.foodchem.2020.126852

[Display omitted] •A novel PL-6 family alginate lyase was characterized.•This enzyme shows high stability under 40 °C as well as in pH 7.0–10.0 conditions.•The degradation pattern of PL-6 family alginate lyase was elucidated.•This study provides a novel insight into PL-6 family alginate lyases’ action mode. Alginate is the main component of brown algae which contributes to a huge biomass. The alginate oligosaccharides (AOs) have been widely used in food, cosmetic and pharmaceutical industries due to their various physiological activities. In this study, we expressed and characterized a novel PL-6 alginate lyase, named OUC-ScCD6. The results indicated that OUC-ScCD6 showed highest activity at 50 °C and pH 9.0. OUC-ScCD6 prefers to degrade poly M blocks and could digest poly G blocks as well. Endolytic action mode towards polysaccharides contributes to the creation of AOs with the degrees of polymerization 2–6. Degradation towards saturated oligosaccharides showed that saturated trisaccharides (M3 and G3) were minimum identifiable substrates. Furthermore, OUC-ScCD6 shows an even-numbered glycosidic bonds preference from non-reducing end which provided clearer insights into the substrate recognition and action mode of PL-6 family alginate lyases.