A major site of bicarbonate effect in system II reaction. Evidence from ESR signal IIvf, fast fluorescence yield changes and delayed light emission |
| |
Authors: | P Jursinic J Warden |
| |
Institution: | Department of Physiology and Biophysics, University of Illinois, Urbana, Ill. 61801 U.S.A. |
| |
Abstract: | In order to determine the major site of bicarbonate action in the electron transport complex of Photosystem II, the following experimental techniques were used: electron spin resonance measurements of Signal IIvf, measurements of chlorophyll a fluorescence yield rise and decay kinetics, and delayed light emission decay. From data obtained using these experimental techniques the following conclusions were made: (1) absence of bicarbonate causes a reversible inactivation of up to 40% of Photosystem II reaction center activity; (2) there is no significant effect of bicarbonate on electron flow from the charge accumulating S state to Z; (3) there is no significant effect of bicarbonate on electron flow from Z to P-680+; (4) electron flow from Q? to the intersystem electron transport pool is inhibited by from 4- to 6-fold under bicarbonate depletion conditions. |
| |
Keywords: | HEPES DCMU 3-(3 4-dichlorophenyl)-1 1-dimethylurea |
本文献已被 ScienceDirect 等数据库收录! |
|