Fig. 2.

Kinetics and bistability of azobenzene isomerization attached at the I328C mutant. (A) Increasing 525-nm light intensity (green bar) to a cell expressing the I328C mutant tethered to MEA-TMA increases activation rates of whole-cell current. Data were fitted by single exponential decay functions (in red). (B) Bar plot summarizing data presented in A shows substantial change of time constant (τ) but not of light-induced current amplitude (normalized to 0.36 mW/mm²) (n = 4 cells; error bars are SEM). (C) Bistability of light-induced currents revealed in the dark following brief photoactivation at 525 nm (green bars, light intensity was set to 4.5 mW/mm²) and brief inactivation at 365 nm (violet bars) in a cell expressing the I328C mutant tethered to MEA-TMA. Note that the basal current is stable in the dark until a new photoactivation of similar amplitude occurs.