|
|||||
|
|
Role of Phosphate and Kinetic Characteristics of Complete Iron Release from Native Pig Spleen Ferritin-Fe |
|
| Authors: | He-Qing Huang Qing-Mei Lin Bo Kong Run-Ying Zeng Yu-Huan Qiao Can-He Chen Feng-Zhang Zhang and Liang-Shu Xu |
| Institution: | (1) Division of Biotechniques, Department of Biology, Xiamen University, Xiamen, 361005, China;(2) Research Center of Environmental Science, Xiamen University, Xiamen, 361005, China;(3) Third Institute of Oceanography, State Oceanic Administration, Xiamen, 361005, China;(4) State Tumor Research Laboratory, Xiamen University, Xiamen, 361005, China;(5) Institute of Molecular and Cell Biology, National University of Singapore, Singapore, 117609 |
| Abstract: | The kinetics for complete iron release showing biphasic behavior from pig spleen ferritin-Fe (PSFF) was measured by spectrophotometry. The native core within the PSFF shell consisted of 1682 hydroxide Fe3+ and 13 phosphate molecules. Inhibition kinetics for complete iron release was measure by differential spectrophotometry in the presence of phosphate; the process was clearly divided into two phases involving a first-order reaction at an increasing rate of 46.5 Fe3+/PSFF/min on the surface of the iron core and a zero-order reaction at a decreasing rate of 6.67 Fe3+/PSFF/min inside the core. The kinetic equation C(PSFF-Fe3+)max – C(PSFF-Fe3+) t ]1/2 = T max –T t gives the transition time between the two rates and represents the complex kinetic characteristics. The rate was directly accelerated twofold by a mixed reducer of dithionite and ascorbic acid. These results suggest that the channel of the PSFF shell may carry out multiple functions for iron metabolism and storage and that the phosphate strongly affects the rate of iron release. |
| Keywords: | Pig spleen ferritin kinetics and order phosphate role and channel function ascorbic acid and dithionite |
| 本文献已被 SpringerLink 等数据库收录！ | |