[Mechanisms of charge separation in photosynthetic reaction centers]

Light quanta absorbed by means of light -- absorbing matrix of pigment molecules are transferred with several special molecules forming the photoreaction centre (PhRC). The following conditions should be met for an effective storage of electron excitation energy in PhRC resulting from charge division: 1) electron transfer from donor to acceptor should proceed in the time less than life time of the initial excited state; 2) this transfer ought to be irreversible to a sufficient degree; 3) the less possible portion of the excitation energy should be lost in this process. Simultaneous fulfilment of these conditions is concerned with certain difficulties. Two means for overcoming these difficulties (multistage process and contribution of conformation degree of freedom) are proposed. Their realization at various stages of charge division involves probable mechanism of PhPC functioning.