Characterization of a novel mucin sulphotransferase activity synthesizing sulphated O-glycan core 1,3-sulphate-Gal beta 1-3GalNAc alpha-R.
A novel sulphotransferase (sulpho-T) activity from rat colonic mucosa was characterized using O-glycan core 1 substrate, Gal beta 1-3GalNAc alpha-benzyl. Derivatives of Gal beta 1-3GalNAc- were used to demonstrate that the 3- and 4-hydroxyl of Gal and the 2-acetamido group of the GalNAc residue of Gal beta 1-3GalNAc alpha-benzyl substrates were important for activity. Sulphated product using Gal beta 1-3GalNAc alpha-benzyl as substrate was analysed by ion spray mass spectrometry, methylation analysis, high-pH anion-exchange chromatography and beta-galactosidase digestion. The results suggested that sulphate was added to the 3-position of the Gal residue. The synthesis of core 2 from core 1 by UDP-GlcNAc: Gal beta 1-3GalNAc beta 6-GlcNAc-transferase was inhibited by sulphation of the Gal residue, indicating that GlcNAc beta 1-6 branching has to precede sulphation in the O-glycan core 1 processing pathway. These data demonstrate several novel pathways in the synthesis of sulphated mucin-type oligosaccharides.
Kuhns
W
W
Research Institute, Hospital for Sick Children, Toronto, Ontario, Canada.
Jain
R K
RK
Matta
K L
KL
Paulsen
H
H
Baker
M A
MA
Geyer
R
R
Brockhausen
I
I
D000818:Animals; D002240:Carbohydrate Sequence; D002645:Chickens; D003106:Colon / Q000201:enzymology; D005260:Female; D006801:Humans; D066298:In Vitro Techniques; D007413:Intestinal Mucosa / Q000201:enzymology; D007700:Kinetics; D008969:Molecular Sequence Data; D015394:Molecular Structure; D009844:Oligosaccharides / Q000096:biosynthesis* / Q000737:chemistry; D010057:Oviducts / Q000201:enzymology; D011134:Polysaccharides / Q000096:biosynthesis* / Q000737:chemistry; D051381:Rats; D013379:Substrate Specificity; D015238:Sulfotransferases / Q000302:isolation & purification / Q000378:metabolism*; D014018:Tissue Distribution
D009844:Oligosaccharides; D011134:Polysaccharides; D015238:Sulfotransferases; C072220:mucus glycoprotein sulfotransferase