Cloning,Expressing and Characterizing a Novel Cold-Adapted Laminarinase from Marine Bacterium Wenyingzhuangia aestuarii OF219

Laminarinases reveal potential application in the field of food and biotechnology.In this research,a novel GH16 family laminarinase,designated as Lam16A_Wa,was cloned from the genome of marine bacterium Wenyingzhuangia aestuarii OF219 and expressed in Escherichia coli.Lam16A_Wa demonstrates a relatively low optimal reaction temperature(35℃)and a cold-adapted feature.Its optimal pH value is 6.0 and is stable in a broad pH range from 3.0 to 11.0.A glycomics strategy was employed to investigate the hydrolytic pattern of Lam16A_Wa.The enzyme was confirmed as a random endo-acting glycoside hydrolase.Its minimum substrate was laminarin pentasaccharide,and the major final products are oligosaccharides,including disaccharide to pentasaccharide.The Lam16A_Wa provides a novel and well-defined tool for the molecular tailoring of laminarin.