Biochemical, biophysical, and biological properties of densonucleosis virus. I. Structural proteins.

The polypeptide composition of highly purified densonucleosis virus was studied by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The viral proteins showed a different behavior in sodium dodecyl sulfate-gels in comparison with the marker proteins. Therefore, the molecular weights were estimated by analyzing the retardation of the electrophoretic mobility of these proteins in gels with increasing polyacrylamide concentrations. Four structural proteins with molecular weights of 49,000, 58,500, 69,000, and 98,000 were found, ant they were designated p49, p59, p69, and p98, respectively. There are several indications that p98 is a dimer of p49. The relative quantity of the structural proteins in a virion suggests that at least p49 (accounting for +/-70% of total protein mass) is a capsid protein and that there will be 12 capsomers per virion.