| Project/Area Number |
01470050
|
|---|
| Research Category |
Grant-in-Aid for General Scientific Research (B)
|
| Allocation Type | Single-year Grants |
|---|
| Research Field |
無機・錯塩・放射化学
|
|---|
| Research Institution | Kyoto University |
|---|
Principal Investigator |
OHYA Hiroaki Kyoto Univ., Fac. Science Ass. Professor, 理学部, 助教授 (00025389)
|
|---|
| Co-Investigator(Kenkyū-buntansha) |
KOHNO Masahiro Jeol Co. Ltd., Aite Div., Manager, 分析機器技術本部, 副課長
|
|---|
| Project Period (FY) |
1989 – 1990
|
| Project Status |
Completed (Fiscal Year 1990)
|
| Budget Amount *help |
¥6,600,000 (Direct Cost: ¥6,600,000)
Fiscal Year 1990: ¥1,500,000 (Direct Cost: ¥1,500,000)
Fiscal Year 1989: ¥5,100,000 (Direct Cost: ¥5,100,000)
|
|---|
| Keywords | Enzymatic Model / Enzynatic Reaction / Intermediate / ESR / ESRET / Multichannel Photometer / SOD / Peroxide Adduct / 三元錯体 |
|---|
| Research Abstract |
Photo- and magneto-chemical studies on microstructure and function of the active sites in typical enzymes have been carried out by using a simultaneous ESR and optical measurement apparatus (ESRET) developed by this project. 1) Fe (tpp) Cl was employed as a model complexes of heme-Fe^<3+> proteins. This complex showed a clear formation of a peroxide adduct of Fe (tpp)(OOR), which is a key intermediate to function as several enzymatic reaction. The ESR and absorption spectra exhibit characteristic features of its formation. 2) By using the Co^<3+>-polyamine and Co^<2+>-(SB)(SB : Shiff base) as models of dioxygenases we have examined reaction mechanisms of catechol dioxygenase reactions. The former complex formed a binary complex with catechols, followed by an addition of O_2 resulting in a ternary complex. In the latter O_2 first formed an oxygen adduct with the complex, and occurred an intramolecular electron transfer reaction. Secondly, catechol as a substrate was oxydized by the cobalt complex to semiquinone. 3) As a typical example of Fe-SOD model Fe^<3+>-EDTA and its analogs were reacted with active oxygen species. It was found by ESRET that two intermediates are formed : One is sideon type Fe^<3+>-O_2^<2-> and the other Fe^<2+>-O_2^-. By using these intermediates as probes of the recation, the reaction mechanism of the SOD was investigated.
|
