In enzymology, an O-fucosylpeptide 3-beta-N-acetylglucosaminyltransferase () is an enzyme that catalyzes the chemical reaction in which a beta-D-GlcNAc residue is transferred from UDP-D-GlcNAc to the fucose residue of a fucosylated protein.
This enzyme belongs to the family of glycosyltransferases, specifically the hexosyltransferases. The systematic name of this enzyme class is UDP-D-GlcNAc:O-L-fucosylpeptide 3-beta-N-acetyl-D-glucosaminyltransferase. This enzyme is also called O-fucosylpeptide beta-1,3-N-acetylglucosaminyltransferase. This enzyme participates in notch signaling pathway.
As of late 2007, two structures have been solved for this class of enzymes, with PDB accession codes and .