Mössbauer spectra of photosystem-I-reaction centres from the blue-green alga Chlorogloea fritschii

Abstract

Substantial amounts of Fe were present in Photosystem-I preparations from the blue-green alga C. fritschii. Changes in the spectra on chemical reduction provide evidence that some of this Fe is very similar to that found in the 4Fe-4S centers of ferredoxins. Such reduced samples also show EPR signals consistent with maximum reduction Fe-S centers A and B of Photosystem I. An unchanged component in the spectra indicates, assuming all centers A and B are reduced, the presence of another Fe-containing species.