RsLOV point mutants. (A) Dark state structure of RsLOV with residues adjacent to the FMN binding pocket targeted for point mutations highlighted in cyan. (B) Residues targeted for point mutations at the RsLOV dimer interface highlighted: S127 (yellow), E129 (blue), A136 (green), A138 (aqua), E142 (pink), R145 (orange), A167 (red).