Some optical properties of Phanta, eCGP123 and selected variants.

1 Minor absorbing species are indicated in parentheses.
2 ΦF was determined for proteins in the ON state and not exposed to photoswitching light.
3 pKa’s were determined by titrating absorption of the anionic species at λmaxabs.
4 Photoswitching depth is defined as the overall % change in the amount of anionic chromophore species (measured at λabsmax) on exposure first to cyan (λpeak, 505) and then violet (λpeak, 405) photoswitching light, compared to the starting condition of protein not exposed to photoswitching light and stored in the dark for 24 h.
5 Photoswitching rates are defined as changes in the amount of anionic chromophore species (measured at λabsmax) and expressed relative for to rate determined for eCGP123. In all cases R2 values >98% were obtained.
6 Abs/Em/Ex data reproduced from Ando et al. 2004.
7 Defined as the ratio between amount of anionic state species in the OFF state relative to the ON state.
INS—Proteins showed evidence of precipitation between pH 4–6
NP—Protein did not photoswitch when illuminated with violet light.
Some optical properties of Phanta, eCGP123 and selected variants.