β-N-Acetylhexosaminidases (EC 3.2.1.52) are a unique family of glycoside hydrolases with dual substrate specificity and a particular reaction mechanism. Though hydrolytic enzymes per se, their good stability, easy recombinant production, absolute stereoselectivity, and a broad substrate specificity predestine these enzymes for challenging applications in carbohydrate synthesis. This mini-review aims to demonstrate the catalytic potential of β-N-acetylhexosaminidases in a range of unusual reactions, processing of unnatural substrates, formation of unexpected products, and demanding reaction designs. The use of unconventional media can considerably alter the progress of transglycosylation reactions. By means of site-directed mutagenesis, novel catalytic machineries can be constructed. Glycosylation of difficult substrates such as sugar nucleotides was accomplished, and the range of afforded glycosidic bonds comprises unique non-reducing sugars. Specific functional groups may be tolerated in the substrate molecule, which makes β-N-acetylhexosaminidases invaluable allies in difficult synthetic problems.

Department of Biomedical Technology Faculty of Biomedical Engineering Czech Technical University Prague Nám Sítná 3105 CZ 272 01 Kladno Czech Republic

Department of Health Care Disciplines and Population Protection Faculty of Biomedical Engineering Czech Technical University Prague Nám Sítná 3105 CZ 272 01 Kladno Czech Republic

Laboratory of Biotransformation Institute of Microbiology Czech Academy of Sciences Vídeňská 1083 CZ 14220 Praha 4 Czech Republic

References provided by Crossref.org

Mutation Hotspot for Changing the Substrate Specificity of β-N-Acetylhexosaminidase: A Library of GlcNAcases

Engineered Glycosidases for the Synthesis of Analogs of Human Milk Oligosaccharides

Dual Substrate Specificity of the Rutinosidase from Aspergillus niger and the Role of Its Substrate Tunnel

Acceptor Specificity of β-N-Acetylhexosaminidase from Talaromyces flavus: A Rational Explanation