FIGURE 9.

Upper panel, the spectral region of the carboxyl group C=O stretching vibration in the time-resolved FTIR spectra of a ChR1/ChR2 chimera, C1C2, which is virtually identical to ChR_5/2. The intermediate spectra are reconstituted from decay-associated spectra obtained by global exponential fitting with three time constants: 92 μs (A), 177 μs (B), and 1.98 ms (C), as well as D (the spectral component at the infinite time). These spectra are reproduced from Fig. 8. Lower panel, time courses of the absorption changes at 1759 cm⁻¹ (red), 1719 cm⁻¹ (green), and 1736 cm⁻¹ (blue) are shown with their global exponential fitting lines (thick lines, E).