Ligamenvirales

Ligamenvirales
Virus classification Edit this classification
(unranked): Virus
Realm: Adnaviria
Kingdom: Zilligvirae
Phylum: Taleaviricota
Class: Tokiviricetes
Order: Ligamenvirales
Families

Ligamenvirales is an order of linear viruses that infect archaea of the phylum Thermoproteota (formerly Crenarchaeota) and have double-stranded DNA genomes.[1] The order was proposed by David Prangishvili and Mart Krupovic in 2012 and subsequently created by the International Committee on Taxonomy of Viruses (ICTV).[2]

Name

The name is derived from the Latin ligamen, meaning string or thread.[citation needed]

Taxonomy

There are three families in this order – Lipothrixviridae, Rudiviridae and Ungulaviridae.[2]

The virons are filamentous with a helical nucleocapsid. At either end are attached either fibers or more complex structures involved in host adhesion.[3][4]

The major coat proteins of both lipothrixviruses and rudiviruses have an unusual four-helix bundle topology.[5][6][7][8] The genome is non-segmented linear double stranded DNA. Viruses from the two families share up to ten genes. The major difference between the two families is that members of the family Rudiviridae are not enveloped, whereas nucleocapsids of lipothrixviruses are surrounded by a lipid membrane. Furthermore, whereas the capsid of rudiviruses is constructed from a single major capsid protein, that of lipothrixviruses is formed from two paralogous major capsid proteins. In both groups of viruses, the major capsid proteins form a claw-like dimer (homodimer in rudiviruses and heterodimer in lipothrixviruses), which wraps around the dsDNA.[citation needed]

Members of the Ligamenvirales are structurally related to archaeal viruses of the family Tristromaviridae which, similar to lipothrixviruses, encode two paralogous major capsid proteins with the same fold as in ligamenviruses.[9] Due to these structural similarities, order Ligamenvirales and family Tristromaviridae were proposed to be unified within a class 'Tokiviricetes' (toki means ‘thread’ in Georgian and viricetes is an official suffix for a virus class).[9]

References

  1. ^ Prangishvili D; Krupovic M (2012). "A new proposed taxon for double-stranded DNA viruses, the order Ligamenvirales". Arch Virol. 157 (4): 791–795. doi:10.1007/s00705-012-1229-7. PMID 22270758.
  2. ^ a b "Virus Taxonomy: 2022 Release". International Committee on Taxonomy of Viruses (ICTV). March 2023. Retrieved 14 September 2023.
  3. ^ "Viral Zone: Lipothrixvirus". ExPASy. Retrieved 14 September 2023.
  4. ^ "Viral Zone: Rudiviridae". ExPASy. Retrieved 14 September 2023.
  5. ^ Goulet A, Blangy S, Redder P, Prangishvili D, Felisberto-Rodrigues C, Forterre P, Campanacci V, Cambillau C (2009) Acidianus filamentous virus 1 coat proteins display a helical fold spanning the filamentous archaeal viruses lineage. PNAS 106 (50) 21155–60
  6. ^ DiMaio, F; Yu, X; Rensen, E; Krupovic, M; Prangishvili, D; Egelman, EH (2015). "Virology. A virus that infects a hyperthermophile encapsidates A-form DNA". Science. 348 (6237): 914–7. doi:10.1126/science.aaa4181. PMC 5512286. PMID 25999507.
  7. ^ Kasson, P; DiMaio, F; Yu, X; Lucas-Staat, S; Krupovic, M; Schouten, S; Prangishvili, D; Egelman, EH (2017). "Model for a novel membrane envelope in a filamentous hyperthermophilic virus". eLife. 6: e26268. doi:10.7554/eLife.26268. PMC 5517147. PMID 28639939.
  8. ^ Liu, Y; Osinski, T; Wang, F; Krupovic, M; Schouten, S; Kasson, P; Prangishvili, D; Egelman, EH (2018). "Structural conservation in a membrane-enveloped filamentous virus infecting a hyperthermophilic acidophile". Nature Communications. 9 (1): 3360. Bibcode:2018NatCo...9.3360L. doi:10.1038/s41467-018-05684-6. PMC 6105669. PMID 30135568.
  9. ^ a b Wang, Fengbin; Baquero, Diana P; Su, Zhangli; Osinski, Tomasz; Prangishvili, David; Egelman, Edward H; Krupovic, Mart (2020). "Structure of a filamentous virus uncovers familial ties within the archaeal virosphere". Virus Evolution. 6 (1): veaa023. doi:10.1093/ve/veaa023. PMC 7189273. PMID 32368353.