Fiber diffraction analysis of cucumber green mottle mosaic virus using limited numbers of heavy-atom derivatives

The structure of cucumber green mottle mosaic virus has been determined from fiber diffraction data to a resolution of 5 A, using only two derivatives and without making any specific assumptions about the molecular structure of the virus. Because of the cylindrical averaging of fiber diffraction data, large numbers of heavy-atom derivatives have been required in previous structure determinations, but it is shown that simplifying assumptions about the overlapping intensities in fiber diffraction are sufficient for structure determination at this resolution using only two derivatives.