Fig. 1: Biliverdin binding to miRFPs and absorption spectra.
From: Real-time observation of tetrapyrrole binding to an engineered bacterial phytochrome

a Biliverdin (BV) structures in miRFP670, miRFP670/C20A and miRFP709. The molecular structures are reproduced from Baloban et al.31; b steady-state UV–vis absorption spectra of BV in aqueous buffer solution (gray), miRFP670 (green), miRFP670/C20A (magenta) and miRFP709 (blue).