Project
Exploring excited state dynamics of fluorescent proteins by X-ray free electron laser (XFEL).
Fluorescent proteins (FPs) have become a widely opted choice for protein labelling in living specimen. Some FPs show unique photoswitching properties (psFPs) with which advanced microscopic techniques such as super-resolution microscopy have been developed. Optimizing the photoswitching properties is crucial for further advancement of the microscopic technologies, and knowledge of molecular bases behind the photoswitching reactions is essential for rational design of improved psFPs. However, since the photoswitchings are excited processes proceeding in femto- to picosecond order, their structural dynamics are inaccessible by traditional synchrotron X-ray crystallography. In this project, we will address this unexplored information by employing the next generation X-ray source, X-ray free electron laser (XFEL). XFEL provides extremely short (10 fs), strong, and coherent X-ray pulses, which enables serial femtosecond X-ray crystallography (SFX). We will also employ ultrafast spectroscopy and QM/MM simulation to acquire complementary information and integrate results with SFX, aiming full understanding of the molecular basis of the photoswitching processes.