Effect of 5'-deoxy-5'-S-isobutyl adenosine (SIBA) on the synthesis of polyoma virus constituents in infected mouse cells

At 100 microM 5'-S-isobutyladenosine (SIBA) inhibits polyoma virus production in infected mouse embryo fibroblasts and in mouse kidney cells, as measured by plaque formation and by haemagglutination assays. SIBA has no significant effect on the synthesis of T and V antigens as well as on viral DNA synthesized in infected cells. Analysis of virus production on CsCl gradients on CsCl gradients showed that in the presence of SIBA reduced amount of heavy viral particles is produced and that part of these particles are pseudovirions containing low density DNA instead of supercoiled viral DNA.