Solution scattering study on the structure of alfalfa mosaic virus strain VRU

Neutron-scattering with contrast variation has been used to derive a model for the radial distribution of protein and RNA in the VRU strain of alfalfa mosaic virus. The RNA is distributed uniformly throughout the interior of the capsid up to a radius of 65 A and the protein coat extends from 65 to 100 A. It was found necessary to distinguish between two regions within the protein coat: one with mainly hydrophobic amino acids and another with more hydrophylic amino acids. Only a very small part of the protein penetrates into the RNA. Using X-ray scattering, no indication was found for long or short-range order in the packing of the RNA in the virion.