(A) Absorbance
spectra for RpBphP2 PAS-GAF-PHY, PAS-GAF, PAS-GAF-PHY
D202A, and PAS-GAF-PHY P465T mutants in the Pr state (black line)
and photoconverted state (gray line); (B) light-minus-dark difference
absorption spectra of RpBphP2 wild-type PAS-GAF-PHY (blue line), PAS-GAF
(red line), D202A (magenta), and P465T (green line).