Characterization of degradation patterns and enzymatic properties of a novel alkali-resistant alginate lyase AlyRm1 from Rubrivirgamarina

Alginate lyase is essential for the production of alginate oligosaccharides (AOSs), which exhibit diverse bioactivities and have numerous applications in the food and pharmaceutical industries. The creation of recombinant alginate lyase by genetic engineering lays a crucial foundation for the commercialization of alginate lyase. This study cloned and expressed the polysaccharide lyase family 6 (PL6) alginate lyase gene alyrm1 from Rubrivirga marina.The optimum temperature and pH for recombinant AlyRm1 are 30 °C and 10.0, respectively. AlyRm1 shows good alkaline stability, for it remained over 80% of the enzyme activity after being incubated at pH 10.0 for 24 h AlyRm1 preferentially degrades PolyM into AOSs with degrees of polymerization (DP) 2–5 and monosaccharides as an endolytic bifunctional lyase. In addition, the analysis of degradation products toward oligosaccharides revealed that the minimal substrate of AlyRm1 is trisaccharide and clarified the degradation patterns.