Notes on Family: Parvoviridae

enveloped pleomorphic
enveloped pleomorphic

Contents

General Description

This family consists of viruses that infect vertebrates or invertebrates and which have linear single-stranded monopartite DNA genomes. The virions and the genomes are small, hence the name (from the latin parvus="small".

Morphology

Virions isometric (icosahedral), not enveloped, 18-26 nm in diameter, made of 60 units of the capsid protein.

Genomen

Linear, single-stranded monopartite DNA, 4-6 kb long.

Genera in the Family

There are two subfamilies and several genera within each, based on genome organisation and phylogenetic analysis:

Subfamily Parvovirinae: infect vertebrates

  • Amdovirus: Organised like Parvovirus but phylogenetically distinct and without PLA2 enzymatic core in the VP1-specific region
  • Bocavirus: Organised like Parvovirus but phylogenetically distinct and with genome about 5.5 kb
  • Dependovirus: DNA molecules have inverted terminal repeats and 3 mRNA promoters; efficient replication usually depends upon helper adeno- or herpes- viruses
  • Erythrovirus: DNA molecules have inverted terminal repeats and 1 mRNA promoter
  • Parvovirus: DNA molecules have terminal hairpins and 2 mRNA promoters; genome about 5.1 kb
Subfamily Densovirinae: infect arthropods (and possibly other invertebrates)
  • Brevidensovirus: DNA 4 kb; virions contain mainly negative sense DNA
  • Densovirus: DNA 6 kb; ambisense coding strategy with structural and non-structural proteins on different strands
  • Iteravirus: DNA 5 kb; virions with similar amounts of each polarity DNA
  • Pefudensovirus: DNA 5.5 kb, organised like Densovirus but phylogenetically distinct and with PLA2 motif located in the C-terminal of the small ORF rather than in VP1