Phase Problems of the Crystal Structure Analysis of Protein

Abstract

The structures of about 100 proteins have been determined since the 6 A structure of myoglobin was reported in 1958. The isomorphous replacement method was mainly used in order to determine the phase angle of each reflection, and the anomalous dispersion effect was also utilized in the recent analysis. The rotation function method and the direct method may be useful, when the molecule is rather large. The refinement procedures, real space ref inemet and energy refinement, were recently developed and were applied to several protein structures.