| Project/Area Number |
01470027
|
|---|
| Research Category |
Grant-in-Aid for General Scientific Research (B)
|
| Allocation Type | Single-year Grants |
|---|
| Research Field |
天然物有機化学
|
|---|
| Research Institution | Tokyo Institute of Technology |
|---|
Principal Investigator |
KAKINUMA Katsumi Tokyo INST. Tech., FAC. Science, Professor, 理学部, 教授 (90092543)
|
|---|
| Project Period (FY) |
1989 – 1991
|
| Project Status |
Completed (Fiscal Year 1991)
|
| Budget Amount *help |
¥8,000,000 (Direct Cost: ¥8,000,000)
Fiscal Year 1991: ¥1,000,000 (Direct Cost: ¥1,000,000)
Fiscal Year 1990: ¥2,500,000 (Direct Cost: ¥2,500,000)
Fiscal Year 1989: ¥4,500,000 (Direct Cost: ¥4,500,000)
|
|---|
| Keywords | Halobacterium halobium / sn-2, 3-di-OMICRON-Phytanyl Giycerol / Archaebacteria / Sulfolobus acidocaldarius / Biosynthesis / Chiral Deuterium Labeling / Triose-phosphate Isomerase / Cheirally Monodeuterated Glycerol / 好酸好熱菌 / エ-テル型膜脂質 / 重水素化グリセロ-ル / 糖代謝 / ホスホリピド / グリセロ-ル代謝 / グリセロ-ル-1-リン酸 |
|---|
| Research Abstract |
Evolutionary intriguing archaebacteria contain 2, 3-di-OMICRON-polyisopranyl glycerol structures as core membrane lipids, which may be regarded as mirror images to the lipids of the eubacterial and eukaryotic cells. In this project, the biosynthetic mechanisms which afford such intriguing stereochemistry of the membrane lipids were studied by the stable isotope-tracer technique and NMR analysis.
1) The absolute stereochemistry of the glycerol moiety of core lipid in halophilic archaebacteria Halobacterium halobium was confirmed by combination of the enantiospecific synthesis of both 1, 2- and 2, 3-di-OMICRON-phytanyl glycerol from D-mannitol and close analysis of their 500MHz ^1H-NMR spectra.
2) The biosynthesis of 2, 3-Di-OMICRON-phytanyl glycerol in H. halobium has been elucidated for the first time from the stereochemical viewpoints. The core lipid appears to be biosynthesized from glycerol and D-glucose via reduction of dihydroxyacetone phosphate or its derivative, during which the s
… More
tereochemistry of C-2 is inverted. In the ether-bond formations, the C-2 and C-3 oxygen atoms of glycerol act as nucleophile. The plausible pathway of the biosynthesis was postulated.
3) A novel and convenient synthetic method of chirally monodeuterated glycerol was developed based on the chirality transcription concept using 1, 2 : 5, 6-di-OMICRON-iopropylidene-alpha-D-ribo-hexofuranos-3-urose as a template.
4) Stereochemistry of the archaebacterial triose-phosphate isomerase reaction was elucidated for the first time by chasing the deuterium of D-[5- ^2H]-and D-[4- ^2H]glucose during the core lipid biosynthesis in Halobacterium halobium, followed by 500 MHz ^1H-NMR comparison of the deuterated lipid and the synthetic sn-2, 3-di-OMICRON-phytanyl (3R) - and - (3S) -[3- ^2H_1]glycerol.
5) The finding that the diglyceryl tetraether lipid of thermoacidophilic archaebacteria Sulfolobus acidocaldarius is biosynthesized from glycerol without inversion of configuration at C-2 suggests a possibility of direct formation of glycerol-1-phosphate rather than glycerol-3-phosphate found in H. halobium. A diversified and contrasting biochemical transformation may be evolved within the archaebacterial species. Less
|
