Figure 8.

Kinetic decomposition of absorption changes in the second part of the photocycle measured on two humidified films, which were prepared from liposomes suspensions at either pH 5.0 (left column) or 8.0 (right column) In both cases the photocycle dynamics is described with four intermediates, which give rise to four kinetic components. (A and B) individual amplitude spectra of kinetic components calculated by FitExp for the four exponentials: τ₁ (green), τ₂ (blue), τ₃ (red), τ₄ (magenta) and their sum (orange), which corresponds to extrapolation for the spectrum that is observed prior to these processes. The spectra in panels C-F are color-coded in the sequence of green-blue-red-magenta for the last four apparent transitions in the photocycle. (C and D) difference spectra recalculated by SchemeFit assuming a unidirectional sequence of intermediates, when each consecutive step is slower than the preceding one. (E and F) absorption spectra reconstruction assuming a ~15% efficiency for conversion into the photocycle. The spectra of the initial states (black) were corrected for scattering. The open circles are the calculated points, and the solid curves are the cubic splines drawn through them.