Project/Area Number |
62580161
|
Research Category |
Grant-in-Aid for General Scientific Research (C)
|
Allocation Type | Single-year Grants |
Research Field |
代謝生物化学
|
Research Institution | The Tokyo Metropolitan Institute of Medical Science(TIMS) |
Principal Investigator |
KAKINUMA Katsuko TIMS, Department of Inflammation Research, 炎症研究部, 室長 (30109946)
|
Co-Investigator(Kenkyū-buntansha) |
田中 昭子 財団法人東京都臨床医学総合研究所, 炎症研究部, 研究員 (80274314)
TSUNAWAKI S. TIMS, Department of Inflammation Research, 炎症研究部, 研究員 (00211384)
KANEDA M. TIMS, Department of Inflammation Research, 炎症研究部, 研究員 (50113494)
FUJII H. TIMS, Department of Inflammation Research, 炎症研究部, 研究員 (70209013)
CHIBA T. TIMS, Department of Inflammation Research, 炎症研究部, 研究員 (20188486)
|
Project Period (FY) |
1987 – 1988
|
Project Status |
Completed (Fiscal Year 1988)
|
Budget Amount *help |
¥2,300,000 (Direct Cost: ¥2,300,000)
Fiscal Year 1988: ¥1,200,000 (Direct Cost: ¥1,200,000)
Fiscal Year 1987: ¥1,100,000 (Direct Cost: ¥1,100,000)
|
Keywords | NADPH oxidase / O^-_-generating enzyme / O_2^-生成酵素 / チトクロムb558 / フラビン酵素 / O<-( / )2>生成酵素 / チトクロムb_<558> / 活性酸素生成酵素 / NADPH oxidase / FAD酵素 |
Research Abstract |
The NADPH (O^-_-generating) oxidase of neutrophils has been thought to be a bransmembrane-electron transport system, with its redox centers such as a b-type cytochrome and a flavin enzyme. We prepared the membrane oxidase from either stimulated or resting neutrophils of pig blood and separated a flavin enzyme and a cytochrome b_<558> fraction from the solubilized oxidase by a single step of preparative isoelectric focussing to avoid denaturation of the redox centers. 1) the flavin enzyme focussed at pI 5.0 was mainly of about 70 kDa molecular mass. The Km value for oxygen was in the range of 72-134 muM, much higher than that of the membrane-oxidase (6muM). 2) The aim of our ESR studies was to characterize a b-type cytochrome, so called "cytochrome b_<558>", located in the NADPH oxidase system in neutrophil membranes. The cytochrome b_<558> fraction revealed severl resonance signls; a low spin signal(s) at g=3.52 (3.23), and non-heme metal signals around g=2 region. The present results of the heme in cytochrome b_<558> are in accord with the absorption spectrum and its insensitivity to KCN and CO, characteristic for a low-spin state of the iron in the heme.
|