Figure 2.

Spectra of purified recombinant pigments and Gt-activation rates. (A) WT or Ala replacement opsins were reconstituted with 11-cis-retinal to form pigments, and 9-dm-pigments were obtained with 9-dm-retinal. Spectra were measured before (solid lines) and after (shaded gray) illumination with orange light. (B) Light-dependent Gt-activation rates of rhodopsins containing 11-cis-retinal (black) or 9-dm-retinal (gray) were determined from GTP[γS] uptake by Gt and are presented relative to the rate of WT reconstituted with 11-cis-retinal. Values from left to right are 100.0%, 21.3%, 45.1%, 3.2%, 141.8%, 22.2%, 5.3%, 4.8%, 18.1%, and 12.0%.