Fuselloviridae is a family of viruses. Sulfolobus species, specifically shibatae, solfataricus, and islandicus, serve as natural hosts. There are two genera and nine species in the family.[1][2] The Fuselloviridae are ubiquitous in high-temperature (≥70 °C), acidic (pH ≤4) hot springs around the world.

Fuselloviridae
Virus classification Edit this classification
(unranked): Virus
Family: Fuselloviridae
Genera
Synonyms
  • Fuselloviridae ICTV 1993
  • SSV1-type phages ICTV 1991
  • SSV-1 family ICTV 1990

Taxonomy

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The family contains the following genera and species:[2]

Structure

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Three slices through tomo­grams showing an SSV1 virion attacheing to S. shibatae host cell surface. Scale bars, 20 nm.[3]

Viruses in Fuselloviridae are enveloped, with lemon-shaped geometries. The diameter is around 60 nm, with a length of 100 nm. Genomes consist of double-stranded circular DNA, around 17.3 kb in length.[1] Biochemical characterization of SSV1, a prototypical fusellovirus, showed that virions are composed of four virus-encoded structural proteins, VP1 to VP4, as well as one DNA-binding chromatin protein of cellular origin. The virion proteins VP1, VP3, and VP4 undergo posttranslational modification by glycosylation, seemingly at multiple sites. VP1 is also proteolytically processed. SSV1 virions contain glycerol dibiphytanyl glycerol tetraether (GDGT) lipids, which appear to be acquired by the virus in a selective manner from the host cytoplasmic membrane.[4]

Genus Structure Symmetry Capsid Genomic arrangement Genomic segmentation
Alphafusellovirus Lemon-shaped Enveloped Circular Monopartite
Betafusellovirus Lemon-shaped Enveloped Circular Monopartite

Life cycle

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Viral replication is cytoplasmic. Entry into the host cell is achieved by adsorption into the host cell. DNA templated transcription is the method of transcription. Sulfolobus shibatae, S. solfataricus, and S. islandicus serve as the natural host.[1] Fuselloviruses are released from the host without causing cell lysis by a budding mechanism, similar to that employed by enveloped eukaryotic viruses.[3]

Genus Host details Tissue tropism Entry details Release details Replication site Assembly site Transmission
Alphafusellovirus Archea: thermolophilic None Injection Budding Cytoplasm Cytoplasm Passive diffusion
Betafusellovirus Archea: thermolophilic None Injection Budding Cytoplasm Cytoplasm Passive diffusion

References

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  1. ^ a b c "Viral Zone". ExPASy. Retrieved 15 June 2015.
  2. ^ a b "Virus Taxonomy: 2020 Release". International Committee on Taxonomy of Viruses (ICTV). March 2021. Retrieved 24 May 2021.
  3. ^ a b Quemin ER, Chlanda P, Sachse M, Forterre P, Prangishvili D, Krupovic M (2016). "Eukaryotic-Like Virus Budding in Archaea". mBio. 7 (5): e01439-16. doi:10.1128/mBio.01439-16. PMC 5021807. PMID 27624130.  
  4. ^ Quemin ER, Pietilä MK, Oksanen HM, Forterre P, Rijpstra WI, Schouten S, Bamford DH, Prangishvili D, Krupovic M (2015). "Sulfolobus spindle-shaped virus 1 contains glycosylated capsid proteins, a cellular chromatin protein, and host-derived lipids". J Virol. 89 (22): 11681–11691. doi:10.1128/JVI.02270-15. PMC 4645638. PMID 26355093.
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