1995 Fiscal Year Final Research Report Summary
Study on the Interaction of Sugar Chain with Protein Moiety in Immunoglobulin G
Project/Area Number |
06680629
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Research Category |
Grant-in-Aid for General Scientific Research (C)
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Allocation Type | Single-year Grants |
Research Field |
Functional biochemistry
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Research Institution | Kansai Medical University |
Principal Investigator |
FUJII Shigeru Kansai Medical University, Professor, 医学部, 教授 (60144482)
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Co-Investigator(Kenkyū-buntansha) |
NAKAGAWA Manabu Kansai Medical University, Assistant, 医学部, 助手 (50261053)
KURODA Kiyo Kansai Medical University, Assistant, 医学部, 助手 (30131436)
|
Project Period (FY) |
1994 – 1995
|
Keywords | Glycoprotein / Structure of Sugar Chain / Protein Structure / NMR / Fluorescent Labeling |
Research Abstract |
Immunoglobulins G normally have one N-liked sugar chain in each heavy subunit, and different molecules contain heterogeneous biantennary complexes. The sugar chains of human IgG1 differ in the distribution of its galactose residues from bovine IgG and human IgG2. In the present study, we examined the branch specificities of beta-galactosidase for free biantennary complexes and for ones of glycoproteins. The specificities for sugar chains of glycoproteins were not necessarily the same to ones for free oligosaccharides. These results suggest that the protein portion interacts with the sugar chains in glycoproteins. The following results were also obtained. (1) Penicillium notatum phospholipase B contained one kind of oligosaccharides and its structure was determined to be a high-mannose type (Man9). (2) The sugar chains of E-cadherin was modified in murine melanoma cells by ectopically-expressed beta1-4 N-acetylglucosaminyltransferase (GnT-III). This modification induced the increased E-cadherin expression. The glycosylated E-cadherin seems to contribute to the suppression of metastasis. (3) A fluorescence assay method for alpha1-6 fucosyltransferase was developed involving a pyridylaminated sugar as a substrate. The sugar chain is linked to an asparagine to keep a ring structure of the reducing end GlcNAc. With this assay method, alpha1-6 fucosyltransferase was purified from porcine brain.
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Research Products
(12 results)