The Impact of Synchrotron Radiation on Protein Crystallography

Abstract

Protein crystallography since the 1950’s has developed into one of the major arms of biology owing to its capacity to reveal the 3 dimensional structure in atomic detail of proteins and other macro-molecules. Because of this it has become an essential platform for understanding many biological processes. The success of protein X-ray analysis rests principally on the power of the experimental methods for determining the phase. In this technique heavy atoms which scatter X-rays strongly are introduced into the crystal — usually by soaking. Providing the crystal organisation is unaffected by this reaction the changes in the X-ray diffraction pattern can be used to locate the heavy atoms, then to calculate the phase angle and hence obtain the electron density from which the structure is interpreted.