AUTHOR=Li Shangyong , Wang Linna , Jung Samil , Lee Beom Suk , He Ningning , Lee Myeong-Sok 

TITLE=Biochemical Characterization of a New Oligoalginate Lyase and Its Biotechnological Application in Laminaria japonica Degradation

JOURNAL=Frontiers in Microbiology

VOLUME=Volume 11 - 2020

YEAR=2020

URL=https://www.frontiersin.org/journals/microbiology/articles/10.3389/fmicb.2020.00316

DOI=10.3389/fmicb.2020.00316

ISSN=1664-302X

ABSTRACT=Oligoalginate lyases belong to family 17 of polysaccharide lyases (PL) that preferred β-D-mannuronic acid (M) into monomeric sugar, providing feedstock for biofuels. The M-preferred substrate recognition and binding mechanism of this family has not been fully elucidated. In this study, we report the cloning, expression and biochemical characterization of a new PL17 oligoalginate lyase, OalV17, from the marine bacterium Vibrio sp. SY01. The recombinant OalV17 showed metal ion independent and detergent resistant properties. Furthermore, OalV17 is an exo-type enzyme that yields alginate monomers as the main product and recognizes alginate disaccharides as the minimal substrate. Site-directed mutagenesis followed by kinetic analysis indicates that the residue Arg231 plays a key role in substrate specificity. Furthermore, a rapid and efficient alginate monomer-producing method was developed directly from Laminaria japonica. These results suggest that OalV17 is a potential candidate for saccharification of alginate.