Portogloboviridae
| Portogloboviridae | |
|---|---|
| |
| Portoglobovirusvirion | |
Virus classification
| |
| (unranked): | Virus |
| Realm: | Varidnaviria(?) |
| Family: | Portogloboviridae |
Portogloboviridaeis afamilyofdsDNA virusesthat infectarchaea.It is a proposed family of therealmVaridnaviria,but ICTV officially puts it asincertae sedisvirus. Viruses in the family are related toHelvetiavirae.Thecapsid proteinsof these viruses and their characteristics are of evolutionary importance for the origin of the otherVaridnaviriaviruses since they seem to retain primordial characters.[1]
Description
[edit]Thevirionsin this family have a capsid with icosahedral geometry and aviral envelopethat protects thegenetic material.The diameter is 83 to 87 nanometers. Thegenomeis circulardsDNAwith a length of 20,222 base pairs. Thegenomecontains 45open reading frames(ORFs), which are closely arranged and occupy 89.1% of the genome. ORFs are generally short, with an average length of 103codons.Virions have 10proteinsranging from 20 to 32 kDa. Of these proteins, 8 code for the capsid and two for the viral envelope, including one that is a verticalsingle jelly roll (SJR) capsid protein.Entry into the host cell is by penetration.Viral replicationoccurs by chronic infection without alytic cycle.[2]
ThePortogloboviridaeviruses together withHalopaniviraleshave evolutionary importance in the evolution of the otherVaridnaviriaviruses since they appear to be relics of how the first viruses of this realm were.Portogloboviridaetogether withHalopaniviralesmay have infected thelast universal common ancestor(LUCA) and originated before that organism.[1]
It has been proposed that it may be related to the origin ofVaridnaviriain the following way.[1]
| Varidnaviria |
| ||||||
Taxonomy
[edit]The family has one genus which has two species:[3]
- Alphaportoglobovirus
| Name | Name | Abbr | GenBank | REFSEQ |
|---|---|---|---|---|
| Alphaportoglobovirus SPV2 | Sulfolobus polyhedral virus 2 | SPV2 | MK064567 | NC_055116 |
| Sulfolobus Alpha portoglobovirus 1 | Sulfolobus polyhedral virus 1 | SPV1 | KY780159 | NC_038017 |
References
[edit]- ^abcKrupovic M, Dolja VV, Koonin EV (14 July 2020)."The LUCA and its complex virome".Nat Rev Microbiol.18(11): 661–670.doi:10.1038/s41579-020-0408-x.PMID32665595.S2CID220516514.Retrieved22 October2020.
- ^Liu Y, Ishino S, Ishino Y, Pehau-Arnaudet G, Krupovic M, Prangishvili D (9 July 2017)."A Novel Type of Polyhedral Viruses Infecting Hyperthermophilic Archaea".J Virol.91(13): e00589-17.doi:10.1128/JVI.00589-17.PMC5469268.PMID28424284.
- ^"Virus Taxonomy: 2022 Release".International Committee on Taxonomy of Viruses (ICTV).March 2023.Retrieved20 August2023.