Single major polypeptide of a calicivirus: characterization by polyacrylamide gel electrophoresis and stabilization of virions by cross-linking with dimethyl suberimidate.
A calicivirus, San Miguel sea lion virus serotype 4, isolate 15FT, externally labelled with 125I, was shown by gel electrophoresis to possess a single major polypeptide. The polypeptide migrated anomalously upon electrophoresis in two sodium dodecyl sulfate (SDS) systems: more slowly than bovine serum albumin in a continuous phosphate-buffered system and more rapidly than bovine serum albumin in a discontinuous system. Estimated molecular weights in the two systems were approximately 71,000 and 64,000, respectively. There was no clear evidence for a minor virion polypeptide. Treatment of purified San Miguel sea lion virions with dimethyl suberimidate, a cross-linking reagent, preserved virion integrity during long-term storage at 4 degrees C. Oligomeric species of the polypeptide were observed upon electrophoresis of products from cross-linked virions. Based upon a preferred polypeptide molecular weight estimate of 71,000 and distribution of oligomeric species, a calicivirion model with 120 monomeric protein units is proposed as an alternative to a 180-unit model.
D000818:Animals; D010872:Caniformia / Q000382:microbiology*; D004120:Dimethyl Suberimidate / Q000494:pharmacology; D004591:Electrophoresis, Polyacrylamide Gel; D008970:Molecular Weight; D010455:Peptides / Q000032:analysis*; D010849:Picornaviridae / Q000032:analysis*; D014764:Viral Proteins / Q000032:analysis*
D010455:Peptides; D014764:Viral Proteins; D004120:Dimethyl Suberimidate