Title : Glycosylation pattern of human
inter-alpha-inhibitor heavy chains
Abstract :
- Human inter-alpha-inhibitor (IalphaI) is a plasma serine-proteinase inhibitor
- It consists of three polypeptide chains covalently linked by a glycosaminoglycan chain: a light chain named bikunin carrying the anti-proteinase activity and two heavy chains , H1 and H2 , which exhibit specific properties, e.g. they interact with hyaluronan thus stabilizing the extracellular matrix
- In this study, using matrix-assisted laser desorption ionization-time-of-flight MS and amino acid sequencing of tryptic peptides , we provide a detailed analysis of the glycosylation pattern of both heavy chains
- H1 carries two complex-type N-glycans of predominantly biantennary structure linked to asparagine residues at positions 256 and 559 respectively
- In contrast, the oligosaccharides attached to H2 are a complex-type N-glycan in the N-terminal region of the protein ( Asn64 ) and three to four type-1 core-structure O-glycans mono- or di-sialylated, clustered in the C-terminal region
- We propose that these O-glycans might function as a recognition signal for the H2 heavy chain
- The biological implications of this hypothesis, notably for the biosynthetic pathway of IalphaI, are discussed
Output (sent_index, trigger,
protein,
sugar,
site):
- 3. glycosylation, , chains, -, -
- 4. linked, , -, predominantly biantennary structure, asparagine residues at positions 256 and 559
- 4. positions, , -, -, asparagine residues at positions 256 and 559
- 5. N-glycan, , -, the N-terminal region, region
- 5. di-sialylated, , -, -, region
Output(Part-Of) (sent_index,
protein,
site):
*Output_Site_Fusion* (sent_index,
protein,
sugar,
site):