Characteristics of Alginate Lyases and Their Molecular Modification: From Irrational to Rational

Alginate lyases are widely distributed in marine invertebrates, microorganisms, and algae. They degrade high-molecular-weight alginate via β-elimination reactions and are essential tools for producing alginate oligosaccharides. To enhance the stability and catalytic ability of natural alginate lyases, various protein engineering strategies have been used to modify them at the molecular level. In recent years, advances in protein crystal chemistry, computational algorithms, and molecular dynamics simulations have elucidated the catalytic structure of alginate lyases and the roles of key residues in great detail. With increasingly precise modification site selection, multiple alginate lyases have achieved significant improvements in enzyme activity or thermal stability. This article reviews the enzymatic properties and engineering strategies for modifying alginate lyases. Although significant progress has been made in research on alginate lyases, future research requires further exploration, including the exploration and characterization of new enzymes, elucidation of catalytic mechanisms, and enzyme engineering-directed modification.