Fluorescence intensities at wavelengths greater than 420et al[20]. Gray trace indicates changes in FRET fluorescence in the presence of ATP only (no GroES), green trace indicates FRET changes in the presence of ATP and equimolar GroES. B. FRET traces for mutants. Black trace indicates SR-1, and Gray trace indicates D398A-RW. Note the differences in time scale between panels A and B.