Some optical properties of Phanta, eCGP123 and selected variants.

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