X-ray Crystallography Using a High Pressure Technique

Abstract

A high pressure technique, called high-pressure cryocooling, has been developed as a method for biophysical and X-ray science studies. The method was developed primarily for crystal cryoprotection and dozens of macromolecular crystals have been successfully cryopreserved, including membrane protein crystals (e.g. a potassium ion channel). In addition, the method was successfully applied to stabilize ligand–protein interactions and to study the pressure effect on the structure of a yellow fluorescent protein, citrine. The procedure was then modified to entrap intermediate enzymatic states of human carbonic anhydrase. More recently, the method was used to study the phase behavior of water and its relationship with protein dynamics. In this presentation, I will discuss the technical details of high pressure cryocooling and its crystallographic applications.