Fig. 4.
Lack of evidence for acceptor photobleaching or “blinking.” (A) Histograms of FRET efficiency calculated from the first (black lines) and second (red lines) halves of each bin in TFE (Upper) and water (Lower). (B) Probabilities of “strings” of consecutive donor photons from time bins belonging to different slices of the efficiency histogram for polyproline-20 (Fig. 3); up and down triangles represent the data in TFE and water, respectively. Data are color coded by slice as indicated in the legend. The solid lines are calculated as p(vD) = (1 − ε)νD, where ε is the mean efficiency in each slice, and νD is the number of consecutive donor photons.