ABSTRACT
The parvovirus genome is a linear, single-stranded DNA molecule with double-stranded hairpin termini. The 3' terminus can serve in vitro as a self-primer for the synthesis of a double-stranded viral DNA intermediate. We have sequenced the nucleotides in the 3' terminus and propose a model for the secondary structure of the terminus and the in vitro origin of replication for the complementary viral DNA strand.
Subject(s)
DNA, Single-Stranded/analysis , DNA, Viral/analysis , Nucleotides/analysis , Parvoviridae/analysis , Parvovirus/analysis , Base Sequence , Coliphages/enzymology , DNA-Directed DNA Polymerase/metabolismSubject(s)
DNA, Single-Stranded/isolation & purification , DNA, Viral/isolation & purification , DNA-Directed DNA Polymerase/isolation & purification , Parvoviridae/analysis , Parvovirus/analysis , Viral Proteins/isolation & purification , Centrifugation, Density Gradient , DNA-Directed DNA Polymerase/metabolism , Hydrogen-Ion Concentration , Parvovirus/enzymologyABSTRACT
Two virus-specific species of newly synthesized DNA were isolated from rat fibroblast cell cultures infected with the Kilham rat virus (RV). These two DNA species were purified; their behavior on hydroxyapatite chromatography and their sedimentation coefficients in sucrose gradients were determined. One of the two species corresponds to the linear double-stranded form of the RV DNA, and the other corresponds to the dimeric duplex form. After denaturation, a fraction of both species showed an intramolecular renaturation; these molecules are composed of viral strand covalently linked to complementary strand. Models for the structure of both species are posposed. Both species may be considered as double-strand replicative intermediates of the single-stranded RV DNA.
