RT Journal Article SR Electronic(1) A1 Ghabrial, S. A. A1 Bibb, J. A. A1 Price, K. H. A1 Havens, W. M. A1 Lesnaw, J. A.YR 1987 T1 The Capsid Polypeptides of the 190S Virus of Helminthosporium Victoriae JF Journal of General Virology, VO 68 IS 7 SP 1791 OP 1800 DO https://doi.org/10.1099/0022-1317-68-7-1791 PB Microbiology Society, SN 1465-2099, AB Summary SDS-PAGE of the 190 V virus of Helminthosporium victoriae, using a discontinuous buffer system, revealed two major capsid polypeptides of mol. wt. 88K and 83K (p88 and p83) and a minor polypeptide, p78. Peptide mapping by both limited proteolysis and selective chemical cleavage showed p83 and p78 to be closely related to p88. The origin of p83/p78 could not be explained by proteolysis of p88 during virus preparation and storage. In rabbit reticulocyte lysates, denatured dsRNA directed the synthesis of a single major translation product which was identical to capsid polypeptide p88 on the basis of coelectrophoresis, immunoprecipitation and peptide mapping. No translation products comparable in size to p83 or p78 were detected in vitro. These data indicated that the capsid of the 190S virus is encoded by a single gene and verified the classification of the virus as a member of the family Totiviridae. Radioiodination of intact virus under conditions considered optimum for surface-specific iodination showed p88 to be more readily available for labelling than p83 or p78. Furthermore, when Western blots of capsid polypeptides were reacted with an antiserum to glutaraldehyde-stabilized virus (190S-G), p88 was more reactive to 190S-G antibodies than was p83/p78. These results suggest p88 is external to p83/p78 in the capsid., UL https://www.microbiologyresearch.org/content/journal/jgv/10.1099/0022-1317-68-7-1791