Replication process of the parvovirus H-1 V. Isolation and characterization of temperature-sensitive H-1 mutants.

Two temperature-sensitive mutants of the parvovirus H-1 have been isolated and characterized. These mutants are distinguishable by the immunofluorescent staining of cells infected by them and by the thermolability of their hemagglutinins. Under restrictive conditions both mutants synthesize a missense capsid protein defective in hemmaglutination. Synthesis of the viral DNA strand was shown to be diminished for both wild-type virus and these mutants at the restrictive temperature of 39.5 C, but the mutants were more defective than the wild type at the less restrictive temperature of 38 C. Replicative form DNA replication was not decreased in these mutants. It is proposed that H-1 requires one of the capsid proteins for the synthesis of the single-stranded progeny DNA.