Selective IR measurement of fluorescent protein chromophore based on TFD-IR technique

Abstract Recently, we developed a novel method based on the transient fluorescence detected IR (TFD-IR) technique to measure the IR spectra of fluorescent molecules in water. In this study, our method was applied for fluorescent proteins and succeeded in the selective IR measurement of chromophores of fluorescent proteins. It was found that the spectral feature of the TFD-IR spectra of TurboGFP and phiYFP, which have the same chromophore but different fluorescent wavelengths, is quite different. This might come from differences in the local structures of the chromophore that interact with the surrounding protein.