Structural proteins of densonucleosis virus isolated from the silkworm, Bombyx mori, infected with the flacherie virus

Four structural proteins were found in highly purified Bombyx densonucleosis virus particles which were analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The molecular weight was estimated from the relative mobility and the retardation coefficient. The major viral protein (VP1), accounting for 65% of the total virion protein, had a molecular weight of about 50,000, and the other three minor proteins (VP2, VP3, VP4) had molecular weights of about 57,000, 70,000, and 77,000, respectively. The Bombyx densonucleosis virus particle contains about 60 molecules of VP1, and VP1 is believed to be capsid protein.