Dual solvent cavities and hydrogen-bond networks define the chromophore environment in a far-red/orange-sensing cyanobacteriochrome.
Cyanobacteriochromes (CBCRs) are bilin-binding photoreceptors that exhibit remarkable spectral diversity and mediate light-dependent signaling in cyanobacteria. Far-red/orange-sensing CBCRs (froCBCRs) have attracted interest because of their unusually red-shifted absorption properties, yet structural information for th...