Of spherical cows, cloudy crystal balls, and proteins

Although proteins perform a vast multitude of tasks in living organisms, perhaps the most fascinating and least well understood is the nanoengine aspect of protein action, where chemical energy is turned into mechanical motion. In order for this to happen a protein must change chemical bond energy into physical displacement via some sort of a conformational change of the protein. The critical first step of this process must be the transient storage (self-trapping) of chemical energy into some metastable strained conformation of the protein. We discuss how the early work of Irwin C. "Gunny" Gunsalus with Hans Frauenfelder and Peter Debrunner led to insights into the picosecond dynamics of proteins, the initial functionally important motions.