ABSTRACT
ABSTRACT Primary steps of photoinduced electron transfer have been studied in
plant reaction centers (PS-I and PS-II), by flash absorption and EPR. In PS-I two questions were investigated : i) the properties of the primary radical pair P-700 , A~ (kinetics of decay ; nature of A^, presumably a specialized chlorophyll a ; decay by recombination to populate the P-700 triplet state) and ii) the nature of the secondary acceptor A^. Extraction-reconstitution experiments indicate that A^ is very probably a molecule of vitamin .
