Chitin is one of the most abundant natural biopolymers and a promising raw material for producing high-value compounds such as chitosans and chitooligosaccharides, which are used in agriculture, medicine, and sustainable biomaterials. This article describes the expression and characterization of a new chitin deacetylase, AcCDA1, from the fungus Absidia coerulea. The study shows that AcCDA1 is active on several chitin-derived substrates, including colloidal chitin, partially deacetylated chitin, chitosans with different degrees of acetylation, and chitooligosaccharides. One of the most important findings is its ability to rapidly produce fully deacetylated chitooligosaccharides from substrates with degrees of polymerization between 3 and 6, a relatively rare feature among known chitin deacetylases. AcCDA1 also showed high catalytic efficiency, especially with penta-N-acetyl chitopentaose, and significantly reduced the degree of acetylation of different chitosans. Its activity on crystalline chitin was more limited, likely because acetyl groups are less accessible in this structure. Overall, the work highlights AcCDA1 as a promising enzymatic tool for producing tailored chitosans and chitooligosaccharides under milder, more controlled, and potentially more sustainable conditions than traditional chemical methods.
Ref.: Barahona-Pérez, L., Martínez-Ranz, M., Forsberg Z., Gracia-Gómez, B., Eijsink, V.G.H. Kidibule,P.E. & Fernández-Lobato, M. Enzymatic deacetylation of oligomeric and polymeric chitin using AcCDA1 from Absidia coerulea. Carbohydrate Polymers 389, 125626 (2026), https://doi.org/10.1016/j.carbpol.2026.125626.
