Enzymatic upgrading of nanochitin using an ancient Lytic Polysaccharide Monooxygenase

Abstract Numerous enzymes have the potential to upgrade biomass converting it into high-tech materials for new technological applications. However, natural enzyme features, such as stability, often limit their use beyond the chemical conversion of the substrate. The development of strategies for the enzymatic conversion of biomass into high-value materials may broaden the range of applications of enzymes and enzyme design techniques. A relevant case is Lytic Polysaccharide Monooxygenase (LPMO), a class of enzymes that catalyzes the oxidative cleavage of glycosidic bonds. Here, we shoe that an ancestral LPMO, unlike its modern counterpart, could efficiently generate chitin nanocrystal (EnCNCh). Physicochemical characterization of EnCNCh demonstrates modifications that make it superior compared to nanochitin obtained either by acid treatment or modern enzymes. We showed that EnCNCh was suitable for controlled 2D and 3D cell cultures, as well as for engineering a biomatrix that combined with graphene oxide (GO) resulted in a hybrid conductive bioink for applications in bioengineering.