Fluorescence properties of E2-Red/Green. Shown are (A) excitation and emission and (B) absorbance spectra of E2-Red/Green. (C) Maturation kinetics of green (green line) and red (red line) fluorescence of E2-Red/Green. For these measurements the green species was excited with 480 ± 10 nm light and emission was recorded at 515 ± 10 nm, and the red species was excited with 540 ± 10 nm light and emission was recorded at 590 ± 10 nm. Also shown are photobleaching kinetics for the red fluorescence of E2-Red/Green and DsRed-Express2 (D) and for the green fluorescence of E2-Red/Green and EGFP (E). The red and green photobleaching measurements were recorded using Texas Red and Endow GFP filter sets, respectively.