Internal Consistency Test and Its Implications for the Initial Steps in Bacterial Photosynthesis

摘要

Comparison of theoretical expressions for superexchange and chemical intermediate mechanisms for electron transfer from the bacteriochlorophyll dimer to a pheophytin reveals a common factor influencing their rates. If the former mechanism is to dominate the latter an internal consistency test becomes possible and is derived. Consequences are investigated for matrix elements, singlet-triplet splitting of the BChl2 +BPh - radical pair and other properties. Two possible alternative mechanisms are also considered. To discriminate among some of the possibilities the study of the effect of an applied electric field on BChl depletion and on the initial rates is suggested. Keywords: Ions; Photosynthesis; Electron transfer; Reaction kinetics; Reprints. (KT)