ABSTRACT
This chapter reviews the structural properties of Papaya Mosaic Virus PMV and its components, the aggregation states of the viral coat protein, the assembly reactions of the coat protein with nucleic acid, and the translational properties of the viral RNA. Various aspects of PMV structure and assembly are compared with those of other helical viruses, in particular Tobacco Mosaic Virus (TMV). The presence of NaCl from 0.025 to 0.2 M inhibits the formation of complete and infectious PMV particles. This inhibition affects both the initiation and elongation processes. It was demonstrated that initiated particles cannot be completed in the presence of 0.1 M or higher molarities of NaCl.5. The salt inhibition effect on assembly may be related to the tendency of the protein to form lower order aggregates in the presence of NaCl. The chemical transformation of cytosine into uracil in PMV-RNA resulted in the loss of recognition and initiation with PMV protein.
