Fig. 2.

Differences in the flavin absorption spectrum between the dark-adapted and light-adapted states of the Slr1694 BLUF photoreceptor. These calculations were performed at the TDDFT LRC-ωPBEh/6–31++G**/MM level of theory. (A) The computed ensemble spectra with the 95% CI shaded and (B) the experimental absorption spectra (adapted with permission from ref. 18 [Copyright 2004, American Chemical Society]). In both the computed and experimental spectra, the flavin S₁ peak at ∼430 nm red shifts by ∼10 nm in the light-adapted state compared to the dark-adapted state.