Viruses Infecting Euryarchaea

K. Porter, B. E. Russ, A. N. Thorburn, M. L. Dyall-Smith

Research output: Chapter in Book/Report/Conference proceedingEncyclopaedia / Dictionary EntryOtherpeer-review

1 Citation (Scopus)


The viruses and virus-like particles of the methanogens, extreme halophiles, and hyperthermophiles of the archaeal kingdom Euryarchaeota are represented by relatively few isolates, but show a remarkable degree of diversity, with three broad morphological categories. Head-and-tail viruses with similar genome structures to head-and-tail bacteriophages infect both extreme halophiles and methanogens. Of these viruses, the methanophage ψM1 and relatives show some sequence similarity to Bacteria and bacteriophages, while the genomes of haloviruses HF1 and HF2 show little similarity to known sequences but are closely related to one another and provide evidence of high recombination rates. Haloviruses ΦCh1 and ΦH form another related group, even though they originate from different environments and infect different hosts, suggesting that similar viruses are widespread. The spindle-shaped haloviruses such as His1 and His2, and the hyperthermophilic VLP PAV1, morphologically resemble archaeal fuselloviruses such as SSV1, but are genetically distinct and form novel virus groups. Finally, spherical viruses such as halovirus SH1 contain an internal lipid layer, similar to tectiviruses (including bacteriophage PRD1) and the crenarchaeal virus STIV, but share no sequence similarity with these viruses and little similarity with other known sequences. Ongoing studies of these unusual viruses continue to reveal unexpected and interesting characteristics.

Original languageEnglish
Title of host publicationEncyclopedia of Virology
EditorsB W J Mahy, M van Regenmortel
Place of PublicationUSA
Number of pages13
ISBN (Electronic)9780123739353
ISBN (Print)9780123744104
Publication statusPublished - 2008
Externally publishedYes


  • Archaea
  • Haloarchaea
  • Halovirus
  • HF1
  • HF2
  • His1
  • His2
  • Methanogen
  • PAV1
  • SH1
  • Thermophili
  • ΦCH1
  • ψM1
  • ψM100
  • ψM2

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