[Effect of hydrogen bonds on the energetics of electron transfer].

For a model system consisting of a special pair of bacteriochlorophyll molecules (P) and a primary quinone with the nearest environment (QA) (which are acceptor and donor in the recombination reaction in Rhodobacter sphaeroides reaction center, respectively), energies of P+QA(-) and PQA states were calculated. Calculations were performed using several stable QA conformations differing by the positions of hydrogen bond protons. Essential influence of proton positions on the energy of vertical transition P+QA(-) --> PQA was shown.