Fig. 7

Spectral properties and thermal stability of in vivo-selected sfGFPS102 and its color derivatives compared to the sfGFP(Sp) protein. a Absorbance spectra were recorded between 250 and 600 nm using a 1-nm step size in the spectrometer and were normalized to 1 for the respective maximum peaks. A.U., absorbance units. b Fluorescence spectra recorded at an excitation wavelength of 485 nm for sfGFPS102, sfGFP(Sp), sfGFPYFPS102 and at 444 nm for sfCFPS102. Curves were normalized to 1 for the respective maximum peak. R.F.U. relative fluorescence units. c Thermal stability was determined by measuring the emission at 530 nm with an excitation of 488 nm while proteins were subjected to heat in steps of 30 s/1 °C from 20 to 99 °C. R.F.U. relative fluorescence units