This glycopeptide is a 16-amino acid modified fragment of mucin 5/MUC5AC, where T* is a GalNac labeled threonine 3. Mucin-type linkages (GalNAc 1-O-Ser/Thr) are initiated by a family of glycosyltransferases known as the UDP-N-acetylgalactosamine:polypeptide N-acetylgalactosaminyltransferases (ppGaNTases). These enzymes transfer GalNAc from the sugar donor UDP-GalNAc to serine and threonine residues, forming an alpha anomeric linkage. The MUC5AC gene, which is mainly expressed in gastric and respiratory mucosae, exhibits 8 amino acid tandemly repeated domain, the consensus peptide TTSTTSAP.
Duperat, V. et al. Biochem. J. 305, 211 (1995); Ten Hagen, K. et al. J. Biol. Chem. 277, 22616 (2002); Van Klinken, B. et al. Am. J. Physiol. Gastrointest. Liver Physiol. 276, G115 (1999); Ten Hagen, K. et al. Glycobiol. 13, 1R (2003).
Sequence (One-Letter Code)
Sequence (Three-Letter Code)
H - Gly - Thr - Thr* - Pro - Ser - Pro - Val - Pro - Thr - Thr - Ser - Thr - Thr - Ser - Ala - Pro - OH (Thr* = GalNAc labeled Thr)