Arenaviruses: purification and physicochemical nature.

The arenaviruses are a group of enveloped viruses having as a unique morphological finding the presence in the virion of granules instead of a defined core. The viruses contain a single-stranded RNA genome, but appreciable amounts of ribosomal-like RNA and 4-6S RNA of host cell origin have been detected. Little information is available on the mode of replication of the viral nucleic acids. A virion-associated RNA-dependent RNA polymerase has been described and there is indirect evidence to suggest that host cell RNA or DNA participates in virus replication. However, the steps in viral RNA synthesis and expression have not yet been elucidated.Pichinde virus contains 2 glycoproteins and 2 polypeptides. Cells infected with Pichinde virus or LCM virus have been shown to produce 2 antigens detectable by immunodiffusion. Both antigens appear to be components of the virion, but the relation between the antigens detected by immunodiffusion and the polypeptides detected by polyacrylamide gel electrophoresis has not yet been clarified.