Biopolymers and cell. 1998; 14 (1): 68 - 78

Theoretical modelling and experimental investigation of nonlinear dynamic precedes in ensemble of photosynlhetic reaction centers

C. A. Abgaryan, A. O. Goushcha, M. T. Kapoustina, V. N. Kharkyanen

The results of theoretical study of dynamic ^I/organization plteno-menon in a specific macromotecutar structure, the photosynthetic reaction center (RC), is presented with accounting of the stochastic effects in the RCs ensemble. The description both the photomobilised electron transfer kinetics and structure conformational transitions is based on the solution of the direct Kolmogorov equealions using the Markov approach. Both the case of thermodynamically equilibrium system and nonequilibrium one were considered for the variables distribution function which describes the diffusion in the confor¬mational coordinate space. The calculations revealed the bistable system behaviour in a certain interval of electron photomobilization rate. The modelling showed a good agreement with the results of experimental investigation of transient absorbance of the RCs from purple bacteria Khodopseudomonas sphaeroides.