Kinetics of the flash-induced electrochromic absorbance change in the presence of background illumination. Turnover rate of the electron transport. I. Isolated intact chloroplasts |
| |
Authors: | Klára Barabás László Zimányi Gy?z? Garab |
| |
Institution: | (1) Institute of Biophysics, Biological Research Center, Hungarian Academy of Sciences, P.O. Box 521, H-6701 Szeged, Hungary;(2) Institute of Plant Physiology, Biological Research Center, Hungarian Academy of Sciences, P.O. Box 521, H-6701 Szeged, Hungary |
| |
Abstract: | We investigated the flash-induced electrochromic absorbance change, A
515, of isolated intact chloroplasts in continuous monochromatic background light of different intensities and wavelengths. From the variation of the amplitude of A
515 in background illumination the steady-state turnover time of electron transport was found to be around 100 msec and the slowest process could be assigned to a photosystem 1 driven cycle. The change of pH induced by nigericin, ATP, or ADP did not modify substantially the turnover time.In contrast to earlier observations the slow rise (10 msec) of A
515 in untreated chloroplasts persists also at high-intensity background illumination exciting both photosystems. The proportion of the slow rise of A
515 in nigericin-treated chloroplasts increases in the presence of background light. This result on the slow rise is discussed in terms of two different models existing in the literature. |
| |
Keywords: | Intact chloroplasts electrochromism slow rise of A
515" target="_blank">gif" alt="Delta" align="BASELINE" BORDER="0">A
515 turnover rate of electron transport |
本文献已被 SpringerLink 等数据库收录! |
|