Molecular Basis for Substrate Recognition and Catalysis by a Marine Bacterial Laminarinase.

ABSTRACT: Laminarin is an abundant algal polysaccharide that serves as carbon storage and fuel to meet the nutrition demands of heterotrophic microbes. Laminarin depolymerization catalyzed by microbial extracellular enzymes initiates remineralization, a key process in ocean biogeochemical cycles. Here, we described a glycoside hydrolase 16 (GH16) family laminarinase from a marine alga-associated Flavobacterium at the biochemical and structural levels. We found that the endolytic enzyme cleaved laminarin with a preference for β-1,3-glycoside linkages and showed transglycosylation activity across a broad range of acceptors. We also solved and compared high-resolution crystal structures of laminarinase in the apo form and in complex with β-1,3-tetrasaccharides, revealing an expanded catalytic cl

SUBMITTER: Yang J 

PROVIDER: S-EPMC7657620 | biostudies-literature | 2020 Nov

REPOSITORIES: biostudies-literature