Photooxidation of the high-potential iron-sulfur center in chloroplasts.
The high-potential iron-sulfur center associated with the g = 1.89-1.90 electron paramagnetic resonance signal in spinach chloroplasts is fully reduced in the dark. It is photooxidized in the presence of 3-(3,4-dichlorophenyl)-1,1-dimethylurea and reduced after illumination with red actinic light in the absence of inhibitors. The light-induced redox changes of the high-potential iron-sulfur center are shown to correlate with those of plastocyanin detected at g = 2.05. Demonstration of light-induced redox changes in the high-potential iron-sulfur center provides support for a functional role of this component in the chloroplast electron transport chain.
Whitmarsh
J
J
Department of Biological Sciences, Purdue University, West Lafayette, Indiana 47907.
Cramer
W A
WA