Figure 5
Analysis of FRET between Phyco-E biotin and Cy5-SA. (A) Fluorescence emission spectra acquired at the region of Cy5 fluorescence emission while exciting the Phyco-E fluorescence at 565 nm in samples containing 5 nM Cy5-SA and different concentrations of PhycoE-biotin as indicated by the color code in panel (B). (B) Corrected fluorescence emission spectra obtained after subtracting spectra acquired at different concentrations of PhycoE-biotin (without Cy5-SA) from the spectra shown in panel (A). (C) Plot of the corrected fluorescence intensity at 670 nm observed in the spectra of panel (B) as a function of PhycoE-biotin concentration. The data were fit to the exponential function f = y0 + a * (1 − exp(−b * x)), where f is the fluorescence intensity (a.u.), x is the PhycoE-biotin concentration (nM) and the fitted parameters were y0 = 6.27 * 103, a = 1.19 * 106, and b = 0.097. (D) Fluorescence emission spectra acquired at the region of Cy5 fluorescence emission while exciting the Phyco-E fluorescence at 565 nm in samples containing 5 nM PhycoE-biotin and different concentrations of Cy5-SA as indicated by the color code. (E) Plot of the corrected fluorescence intensity at 670 nm observed in the spectra of panel (D) as a function of Cy5-SA concentration. The data were fit to the exponential function f = y0 + a * (1 − exp(−b * x)), where f is the fluorescence intensity (a.u.), x is the Cy5-SA concentration (nM) and the fitted parameters were y0 = 2.66 * 104, a = 2.69 * 104, and b = 0.472.
