The first report of enzymatic transglycosylation catalyzed by family GH84 N-acetyl-β-d-glucosaminidase using a sugar oxazoline derivative as a glycosyl donor.

O-Glycosylated N-acetyl-β-d-glucosamine-selective N-acetyl-β-d-glucosaminidase (O-GlcNAcase), belonging to glycoside hydrolase family 84 (GH84), is known as a retaining glycosidase with the possibility of enzymatic transglycosylation. However, no enzymatic transglycosylation catalyzed by GH84 O-GlcNAcase has been reported. Here, enzymatic transglycosylation catalyzed by GH84 O-GlcNAcase was first reported. The enzymatic transglycosylation catalyzed by the GH84 O-GlcNAcase from Bacteroides thetaiotaomicron (BtGH84 O-GlcNAcase) was attained using 1,2-oxazoline derivative of N-acetyl-d-glucosamine (GlcNAc oxazoline) as a glycosyl donor substrate. The β-linked N-acetyl-d-glucosamine (GlcNAc) derivative was enzymatically synthesized using N-(2-hydroxyethyl)acrylamide as an acceptor substrate. Interestingly, the β1,6-linked disaccharide derivative of GlcNAc was also obtained in the case of using the GlcNAc derivative with a triazole-linked acrylamide group as an acceptor substrate. Additionally, a one-pot chemo-enzymatic transglycosylation starting from unprotected GlcNAc through GlcNAc oxazoline successfully showed through the combination with the direct synthesis of GlcNAc oxazoline in water and the enzymatic transglycosylation.