What is mucin-type O-glycosylation?
Mucin-type O-glycosylation is a widespread post-translational modification of proteins found in the entire animal kingdom, but also in higher plants. The structural complexity of the chains initiated by O-linked GalNAc exceeds that of N-linked chains by far.
What is O-linked glycosylation?
O-linked glycosylation is the attachment of a sugar molecule to the oxygen atom of serine (Ser) or threonine (Thr) residues in a protein. O-glycosylation is a post-translational modification that occurs after the protein has been synthesised.
What is N and O-linked glycosylation?
N-linked glycosylation requires participation of a special lipid called dolichol phosphate. O-linked glycans attached to the hydroxyl oxygen of serine, threonine, tyrosine, hydroxylysine, or hydroxyproline side-chains, or to oxygens on lipids such as ceramide.
What enzymes are responsible for initiating mucin type glycosylation?
Mucin-type O-glycosylation is unique among various types of glycosylation in that it is initiated by a large family of enzymes (UDP-GalNAc:polypeptide N-acetylgalactosaminyltransferases (ppGalNAc-Ts)2 or GalNAc transferases in mammals and PGANTs in Drosophila; EC 2.4. 1.41).
What is the difference between N and O links?
Two common types of glycans, N-linked and O-linked, have been extensively analyzed in the last decades. N-glycans are typically released from glycoproteins by enzymes, while O-glycans are released from glycoproteins by chemical methods.
Why are proteins O-glycosylated?
Steric interactions between carbohydrate and peptide within these clusters induce the peptide core to adopt a stiff and extended conformation and this conformational effect appears to represent a major function of O-glycosylation.
What is O-linked glycosylation quizlet?
O-linked glycosylation is the attachment of a sugar molecule to an oxygen atom in an amino acid residue in a protein.