Kinetic model for electron and proton transport in chloroplasts with a nonuniform distribution of protein complexes in thylakoid membranes

A mathematical model for describing electron and proton transport in chloroplasts of higher plants with nonuniform distribution of photosystem 1 (PS1) and photosystem 2 (PS2) between granal and stromal thylakoids was proposed. Along with the noncyclic (linear) electron transport from PS2 to terminal acceptor PS1, we considered cyclic electron transport around PS1, ATP synthesis coupled to transmembrane proton transfer through ATP synthase, and ATP consumption in the Calvin cycle. Numerical simulations of the kinetics of the photoinduced redox transformations of the primary PS1 donor (P₇₀₀) and the behavior of pH in the intrathylakoid space (pH_i) and interthylakoid space (pH₀), as well as the time evolution of the ATP concentration for various conditions of the functioning of the chloroplast were performed.