Fig. 5: Colour prediction for biliverdin in water and comparison with experimental data.

A, B Populations and structures of biliverdin protonated forms depending on pH. C colour prediction of biliverdin in implicit water based on a single optimised conformation. D Ensemble-based colour predictions for biliverdin in explicit water with 0.1 M sodium chloride. E Experimental biliverdin colour dependence on pH. F A comparison of biliverdin spectra: experimental at pH 8 which predominantly contains the S10001 form, ensemble-based colour prediction based on the coil-like conformation of S10001 and its extended conformation stabilised by hydrogen bonds. The amount of absorbed light is given as a proportion and varies between 0 and 1. G Representative structures of the extended and coil-like conformations.