Analyses of the virion
polypeptides and genomes of several
Phlebotomus fever group viruses, Karimabad, Punta Toro, Chagres, and the
sandfly fever Sicilian serotype viruses, have established that they are biochemically similar to the accepted members of the Bunyaviridae family. Like snowshoe hare virus (a member of the California serogroup of the Bunyavirus genus of the Bunyaviridae family), Karimabad, Punta Toro, Chagres, and the
sandfly fever Sicilian serotype viruses all have three
viral RNA species, designated large (L), medium (M), and small (S).
Oligonucleotide fingerprint analyses of Karimabad and Punta Toro virus
RNA species indicated that their L, M, and S
RNA species are unique. By
polyacrylamide gel electrophoresis it was determined for Karimabad virus that the apparent molecular weights of its L, M, and S
RNA species are 2.6 X 10(6), 2.2 X 10(6), and 0.8 X 10(6), respectively. For Punta Toro virus, the apparent molecular weights of its L, M, and S
RNA species are 2.8 X 10(6), 1.8 X 10(6), and 0.75 X 10(6), respectively. The major internal nucleocapsid (N)
protein of Karimabad virus was found to have a molecular weight of 21 X 10(3). A similar
polypeptide size class was identified in preparations of
sandfly fever Sicilian serotype, Chagres, and Punta Toro viruses. The Karimabad virus
glycoproteins formed the external surface projections on virus particles and could be removed from virus preparations by
protease treatment. The
glycoproteins in an unreduced sample could be resolved into two size classes by
sodium dodecyl sulfate-
polyacrylamide gel electrophoresis. They had apparent molecular weights of 62 X 10(3) and 50 X 10(3) in continuous
polyacrylamide gels. When Karimabad virus preparations were reduced with 1% beta-
mercaptoethanol, prior to resolution by continuous
polyacrylamide gel electrophoresis, all the viral
glycoprotein was recovered in a single size class, having an apparent molecular weight of 62 X 10(3). Two or three major virion
polypeptides have been identified in preparations of Punta Toro, Chagres, and
sandfly fever Sicilian serotype viruses.