Infrared temperature-jump study of the folding dynamics of alpha-helices and beta-hairpins.

The laser-induced temperature-jump (T-jump) technique in conjunction with infrared spectroscopy provides a versatile means to study the early events in protein folding. Compared with the commonly used stopped-flow kinetic methods, the T-jump initiation technique offers a faster time resolution. It allows the study of protein folding processes occurring on the nanosecond-to-microsecond time-scales. In addition, infrared spectroscopy is a powerful tool for characterizing backbone conformation and dynamics. In this chapter, we mainly discuss the application of this technique to the study of the helix-coil transition dynamics and the mechanism of beta-hairpin formation.