| 1.Research Institution | Osaka University | |
| 2.Research Area | Life Sciences | |
| 3.Research Field | Structure and Functional Control Mechanism of Biomolecules (Structural Biology and Functional Molecules) | |
| 4.Term of Project | FY 1997 〜 FY 2001 | |
| 5.Project Number | 97L00502 | |
| 6.Title of Project | Glycobiochemistry − Structure and Functions |
| Name | Institution,Department | Title of Position |
| Shoichi Kusumoto | Osaka University, Graduate School of Science | Professor |
8.Core Members
| Names | Institution,Department | Title of Position |
| Sumihiro Hase | Osaka University, Graduate School of Science | Professor |
| Masaki Saito | Meiji Pharmaceutical University, Graduate School of Pharmaceutical Sciences | Professor |
9.Summary of Research Results
|
Biological functions of sugar chains and glycoconjugates were studied on the basis of their chemical structures and interaction
with their specific recognition proteins and/or metabolic enzymes. Improved pyridylamination was successfully applied to high
sensitivity detection, isolation and structural determination of free cytosolic oligosaccharides and sugar chains of glycoproteins.
The presence of brain-specific sugar chains was thus detected and tissue-specific occurrence of their receptors was observed.
Study was also focused on the structure and recognition of bacterial cell surface glycoconjugates which activate the defense
system of innate immunity in higher animals. Various structural analogues and isotopically labeled derivatives of lipid A, the
active entity of endotoxic lipopolysaccharide, were synthesized, and their three dimensional conformation and supramolecular
assembly deduced. The recognition system of lipopolysaccharide was also studied with the aid of synthetic lipid A analogues as
homogeneous probes. Interaction of heparin and platelets and activation of the latter were analyzed on the molecular basis:
specific key sulfated oligosaccharides were detected in heparin. A protein responsible for heparin binding was detected,
isolated, and characterized. Genomic sequence of GM3 synthase (sialyltransferase-1) was determined, expressed in
Escherichia coli and other cell lines. Genetic regulation of this enzyme, which produces the first biosynthetic member of
ganglioside family, provided important information on the role of sugar chains on glycolipids. Production of an active soluble
form of the enzyme initiated the study on its recognition mechanism of substrates. |
10.Key Words
(1)sugar chains、(2)glycoproteins、(3)glycolipids
(4)ganglyosides、(5)heparin、(6)lipopolysaccharides
(7)pyridylamination、(8)glycosylation、(9)sialyltransferase