The primary reaction of photosystem II in the D1‐D2‐cytochrome <i>b</i>‐559 complex

Abstract

Flash‐induced absorbance changes in the picosecond and nanosecond time range have been measured in the ‘D1‐D2‐cyt b ‐559 complex’ isolated from photosystem II membranes. The results indicate the efficient formation of the primary radical pair P680 + pheophytin − , which had a lifetime of about 36 ns, and the presence of unconnected chlorophyll in this preparation. It is concluded that the complex contains the active photosystem II reaction center, and that this reaction center contains at most 4 chlorophyll a molecules.