Laser temperature-jump spectroscopy of intrinsically disordered proteins

Laser temperature-jump methods allow an experimenter to study the kinetics and dynamics of very rapid solution-phase processes, including conformational dynamics of biomolecules on time scales of nanoseconds and microseconds. The combination of laser temperature-jump (T-jump) excitation and appropriate optical detection techniques such as fluorescence energy transfer allows the study of intramolecular and intermolecular conformational changes and interactions that occur during protein folding and binding. This article describes the application of the laser temperature-jump method to UV-visible fluorescence studies of the coupled folding and binding of intrinsically disordered proteins. We emphasize the practical aspects of instrument alignment and optimization, sample preparation, and data collection using fluorescently labeled peptides with UV laser excitation.