Nucleocytoviricota

Last updated
Nucleocytoviricota
Virus classification OOjs UI icon edit-ltr.svg
(unranked): Virus
Realm: Varidnaviria
Kingdom: Bamfordvirae
Phylum:Nucleocytoviricota
Classes

See text

Synonyms

Megavirales [1]

Nucleocytoviricota is a phylum of viruses. [2] Members of the phylum are also known as the nucleocytoplasmic large DNA viruses (NCLDV), which serves as the basis of the name of the phylum with the suffix -viricota for virus phylum. These viruses are referred to as nucleocytoplasmic because they are often able to replicate in both the host's cell nucleus and cytoplasm. [3]

Contents

The phylum is notable for containing the giant viruses. [4] [1] There are nine families of NCLDVs that all share certain genomic and structural characteristics; however, it is uncertain whether the similarities of the different families of this group have a common viral ancestor. [5] One feature of this group is a large genome and the presence of many genes involved in DNA repair, DNA replication, transcription, and translation. Typically, viruses with smaller genomes do not contain genes for these processes. Most of the viruses in this family also replicate in both the host's nucleus and cytoplasm, thus the name nucleocytoplasmic.

There are 47 NCLDV core genes currently recognised. These include four key proteins involved in DNA replication and repair: the enzymes DNA polymerase family B, the topoisomerase II A, the FLAP endonuclease and the processing factor proliferating cell nuclear antigen. Other proteins include DNA dependent RNA polymerase II and transcription factor II B.

Taxonomy

The following classes and orders are recognized, under which are families mentioned in this article:

The unrecognized families are parenthesized and placed in the most likely location.

Hosts

Host organisms typically include protozoa, invertebrates and eukaryotic algae. The class Pokkesviricetes infects familiar vertebrates, including multiple farm animals and humans.

Phylogenetic tree of phylum Nucleocytoviricota on base of Subramaniam et al. (2020). MBio-2020-Subramaniam-e02938-19.F3.large.Tree (annotated).svg
Phylogenetic tree of phylum Nucleocytoviricota on base of Subramaniam et al. (2020).

Examples

Ascoviridae

Order Pimascovirales. Members of the family Ascoviridae come in different shapes. Some can be rod-shaped, while others are oval. They measure up to 130 nm wide and 400 nm long. These viruses have circular double stranded DNA that have a length of about 100–200 kilobase pairs. They infect lepidopteran insect larvae and can infect through parasitoid wasps. Once they infect they replicate and cause death in insect pest. [7] Ascoviridae can have up to 180 genes in its genome. The replication of this virus takes place in the nucleus of the host cell. When it replicates, it causes the nucleus to increase in size and eventually burst. After, the virion starts to form and spread. [8]

Asfarviridae

Order Asfuvirales. A member of the family Asfarviridae is known as an asfarvirus. This virus is the cause of African swine fever. Some of the symptoms for this flu include fever, high pulse, fast breathing, and it can cause death. These symptoms can be similar to those from hog cholera, the difference is that the African swine flu can not be cured. There is no vaccine developed to fight this virus. [9]

Iridoviridae

Order Pimascovirales. The Iridoviridae have linear double stranded DNA genomes up to 220 kilobases long and can code for about 211 proteins. The capsid of this virion is icosahedral shaped and can be up to 350 nm wide. The replication cycle of this virus begins in the nucleus of the host and end in the cytoplasm. Some viruses of this family are often found infecting fish and amphibians while other are found in insect and crustaceans. [10] The Andrias davidianus ranavirus (ADRV), a member of the family Iridoviridae , encodes a protein (Rad2 homolog) that has a key role in the repair of DNA by homologous recombination, and in double-strand break repair. [11]

Marseilleviridae

Order Pimascovirales. The Marseilleviridae viruses have double stranded DNA genomes that are about 368 kilobases long. Members of the family can have about 457 open reading frames (ORFs) in its genome. The host organisms are amoebae. Once it infects, viral replication takes place in virus factories in the cytoplasm. It was found that the genome of the family Marseilleviridae codes for about 28 different proteins. [12]  The capsid of the marseillevirus is about 250 nm wide with a geometry shape of an icosahedral. The replication of this virus usually occurs near the nucleus once it infects the amoeba. Once the virus infects it can cause a shape change in the host's nucleus. [13]

Mimiviridae

Order Imitervirales. The Megaviridae contains some of the largest viruses ever discovered. They have linear double stranded DNA genomes with a length of 1,259,197 base pairs, which is larger than some small bacteria. Within this genome 1,100 proteins are coded. 74.76% of the base pairs are represented by thymine and adenine. The Megaviridae virus can be found infecting acanthamoeba or other protozoan clades.  Once the virus infects the host, the replication cycle takes place in the cytoplasm. Within the genome, DNA repair enzymes can be found. These are used when the DNA is harmed such as when it is exposed to ionizing radiation or UV light. [14] Three enzymes employed in DNA base excision repair were characterized from Mimivirus. [15] The pathway of DNA base excision repair (BER) was experimentally reconstituted using the purified recombinant proteins AP endonuclease (mvAPE), uracil-DNA glycosylase (mvUDG), and DNA polymerase X protein (mvPolX). [15] When reconstituted in vitro, mvAPE, mvUDG and mvPolX were found to function cohesively to repair uracil-containing DNA mainly by long patch base excision repair. [15] Thus these processes likely participate in the BER pathway early in the Mimivirus life cycle. [15] Cafeteria roenbergensis, a giant virus of the Mimiviridae family, also encodes enzymes for DNA repair. [16]

Traditionally only these viruses have been grouped into a family Mimiviridae. Later it appeared that the viruses of the Organic Lake Phycodna Group (OLPG) are more related to Mimiviruses than to Phycodnaviruses. For this reason it has been proposed adding them to legacy Mimiviridae as new subfamily Mesomimivirinae in order to form the more comprehensive family Megaviridae. For this reason, the term Mimiviridae was used sensu lato synonymous with Megaviridae. [17] [18] [19] [20] [21] [22] However, since the ICTV has created a new order Imitervirales officially containing the (legacy) Mimiviridae, proposed Mesomimivirinae are proposed to be upgraded as a new family Mesomimiviridae, i. e. as sister family of legacy Mimiviridae (within this order).

Pandoraviridae

Possibly order Algavirales. Pandoraviridae Discovered in 2013 from a coastal water sample in Chile. It is mostly found infecting amoebae. It has a length of 1 micrometer long and .5 micrometer wide. Its genome can be up to 2.5 million base pairs long. [23] The replication of this virus takes place in the cytoplasm. Like other giant viruses, it affects the host's nucleus and can take up to 15 hours to start infecting. [24] Although it is found in water, it does not affect humans, it may actually help us by increasing the production of oxygen in aquatic environments. [25]  

Phycodnaviridae

Order Algavirales. The Phycodnaviridae are icosahedral in shape with a double-stranded DNA molecule. Some members of this family can have a linear double-stranded DNA while others have a circular double stranded DNA. The genome has been found to be up to 560 kilobases in length. Up to 50% of the DNA can be represented by guanine or cytosine. This virus is known to infect algae, which means it is found in the ocean. [26]

Pithoviridae

Order Pimascovirales. The Pithoviridae have only two known representatives. These viruses infects amoebas and can survive in low temperatures. For years this virus was believed to be frozen, but due to climate change it has begun to show up again. [27]  This is a double stranded DNA virus with its size being 610 kilobases long. The genome is estimated to code for 476 open reading frames. The viron is rod shaped with a length of 1,100 nm long and 500 nm in diameter. [28]

Poxviridae

Order Chitovirales. The Poxviridae have a linear double-stranded DNA molecule that can have a length of up to 230 kilobases. The replication of these viruses takes place in the cytoplasm. Smallpox, cowpox, and other pox viruses belong to this family. [29]  

Mininucleoviridae

Genome maps of the crustacean viruses PaV1, DhV1 and CmV1 (proposed family Mininucleoviridae). MBio-2020-Subramaniam-e02938-19.F1.large.Genomes.jpg
Genome maps of the crustacean viruses PaV1, DhV1 and CmV1 (proposed family Mininucleoviridae).

Possibly order Pimascovirales. A new family has been proposed — Mininucleoviridae — for a family of large viruses that replicate in crustacea. [6] Members of this proposed family include Carcinus maenas virus 1 (CmV1), [note 1] Dikerogammarus haemobaphes virus 1 (DhV1), [note 2] and Panulirus argus virus 1 (PaV1). [note 3]

Unclassified taxa

Phylogenetics

The general consensus is that Iridoviridae Ascoviridae are closely related sister taxa in a clade. Pithovirus , Iridoviridae Ascoviridae and Marseillevirus form a PIM or MAPI clade ( Pimascovirales [2] ) in trees built from conserved proteins. [6] The sister clade to PIM/MAPI is a clade made out of Algavirales [2] (Phycodnaviridae, Pandoraviridae), and possibly Imitervirales [2] /Mimiviridae ("P2" thereafter). [35] Poxviridae is consistently treated as a basal branch. Asfarviridae is either a sister group to Poxviridae (building together Pokkesviricetes ) [2] or a member of the P2 clade. [36] The ICTV classification, as of 2019, matches the general shape of the tree.

The origin of the NCLDVs may predate that of their eukaryotic hosts, judging from their RNA polymerase structures. [36]

See also

Notes

Related Research Articles

<span class="mw-page-title-main">DNA virus</span> Virus that has DNA as its genetic material

A DNA virus is a virus that has a genome made of deoxyribonucleic acid (DNA) that is replicated by a DNA polymerase. They can be divided between those that have two strands of DNA in their genome, called double-stranded DNA (dsDNA) viruses, and those that have one strand of DNA in their genome, called single-stranded DNA (ssDNA) viruses. dsDNA viruses primarily belong to two realms: Duplodnaviria and Varidnaviria, and ssDNA viruses are almost exclusively assigned to the realm Monodnaviria, which also includes some dsDNA viruses. Additionally, many DNA viruses are unassigned to higher taxa. Reverse transcribing viruses, which have a DNA genome that is replicated through an RNA intermediate by a reverse transcriptase, are classified into the kingdom Pararnavirae in the realm Riboviria.

<i>Hepadnaviridae</i> Family of viruses

Hepadnaviridae is a family of viruses. Humans, apes, and birds serve as natural hosts. There are currently 18 species in this family, divided among 5 genera. Its best-known member is hepatitis B virus. Diseases associated with this family include: liver infections, such as hepatitis, hepatocellular carcinomas, and cirrhosis. It is the sole accepted family in the order Blubervirales.

<i>Geminiviridae</i> Family of viruses

Geminiviridae is a family of plant viruses that encode their genetic information on a circular genome of single-stranded (ss) DNA. There are 520 species in this family, assigned to 14 genera. Diseases associated with this family include: bright yellow mosaic, yellow mosaic, yellow mottle, leaf curling, stunting, streaks, reduced yields. They have single-stranded circular DNA genomes encoding genes that diverge in both directions from a virion strand origin of replication. According to the Baltimore classification they are considered class II viruses. It is the largest known family of single stranded DNA viruses.

Pseudoviridae is a family of viruses, which includes three genera.

Phycodnaviridae is a family of large (100–560 kb) double-stranded DNA viruses that infect marine or freshwater eukaryotic algae. Viruses within this family have a similar morphology, with an icosahedral capsid. As of 2014, there were 33 species in this family, divided among 6 genera. This family belongs to a super-group of large viruses known as nucleocytoplasmic large DNA viruses. Evidence was published in 2014 suggesting that specific strains of Phycodnaviridae might infect humans rather than just algal species, as was previously believed. Most genera under this family enter the host cell by cell receptor endocytosis and replicate in the nucleus. Phycodnaviridae play important ecological roles by regulating the growth and productivity of their algal hosts. Algal species such Heterosigma akashiwo and the genus Chrysochromulina can form dense blooms which can be damaging to fisheries, resulting in losses in the aquaculture industry. Heterosigma akashiwo virus (HaV) has been suggested for use as a microbial agent to prevent the recurrence of toxic red tides produced by this algal species. Phycodnaviridae cause death and lysis of freshwater and marine algal species, liberating organic carbon, nitrogen and phosphorus into the water, providing nutrients for the microbial loop.

<i>Iridoviridae</i> Family of viruses

Iridoviridae is a family of viruses with double-stranded DNA genomes. Amphibians, fish, and invertebrates such as arthropods serve as natural hosts. There are currently 22 species in this family, divided among two subfamilies and seven genera.

<i>Mimiviridae</i> Family of viruses

Mimiviridae is a family of viruses. Amoeba and other protists serve as natural hosts. The family is divided in up to 4 subfamilies. Viruses in this family belong to the nucleocytoplasmic large DNA virus clade (NCLDV), also referred to as giant viruses.

Mamavirus is a large and complex virus in the Group I family Mimiviridae. The virus is exceptionally large, and larger than many bacteria. Mamavirus and other mimiviridae belong to nucleocytoplasmic large DNA virus (NCLDVs) family. Mamavirus can be compared to the similar complex virus mimivirus; mamavirus was so named because it is similar to but larger than mimivirus.

<i>Cafeteria roenbergensis virus</i> Species of virus

Cafeteria roenbergensis virus (CroV) is a giant virus that infects the marine bicosoecid flagellate Cafeteria roenbergensis, a member of the microzooplankton community.

Lymphocystivirus is a genus of viruses, in the family Iridoviridae. Fish serve as natural hosts. There are four species in this genus. Diseases associated with this genus include: tumor-like growths on the skin.

A giant virus, sometimes referred to as a girus, is a very large virus, some of which are larger than typical bacteria. All known giant viruses belong to the phylum Nucleocytoviricota.

<i>Marseilleviridae</i> Family of viruses

Marseilleviridae is a family of viruses first named in 2012. The genomes of these viruses are double-stranded DNA. Amoeba are often hosts, but there is evidence that they are found in humans as well. The family contains one genus and four species, two of which are unassigned to a genus. It is a member of the nucleocytoplasmic large DNA viruses clade.

Dinodnavirus is a genus of viruses that infect dinoflagellates. This genus belongs to the clade of nucleocytoplasmic large DNA viruses. The only species in the genus is Heterocapsa circularisquama DNA virus 01.

<i>Alphapithovirus</i> Genus of viruses

Alphapithovirus, is a genus of giant virus known from two species, Alphapithovirus sibericum, which infects amoebas, and Alphapithovirus massiliense. It is DNA-based and is a member of the nucleocytoplasmic large DNA viruses clade. It was discovered in 2014, when a viable specimen was found in a 30,000-year-old ice core harvested from permafrost in Siberia, Russia.

<span class="mw-page-title-main">Zamilon virophage</span> Virus type

Mimivirus-dependent virus Zamilon, or Zamilon, is a virophage, a group of small DNA viruses that infect protists and require a helper virus to replicate; they are a type of satellite virus. Discovered in 2013 in Tunisia, infecting Acanthamoeba polyphaga amoebae, Zamilon most closely resembles Sputnik, the first virophage to be discovered. The name is Arabic for "the neighbour". Its spherical particle is 50–60 nm in diameter, and contains a circular double-stranded DNA genome of around 17 kb, which is predicted to encode 20 polypeptides. A related strain, Zamilon 2, has been identified in North America.

Polintons are large DNA transposons which contain genes with homology to viral proteins and which are often found in eukaryotic genomes. They were first discovered in the mid-2000s and are the largest and most complex known DNA transposons. Polintons encode up to 10 individual proteins and derive their name from two key proteins, a DNA polymerase and a retroviral-like integrase.

<i>Genomoviridae</i> Family of viruses

Genomoviridae is a family of single stranded DNA viruses that mainly infect fungi. The genomes of this family are small. The genomes are circular single-stranded DNA and encode rolling-circle replication initiation proteins (Rep) and unique capsid proteins. In Rep-based phylogenies, genomoviruses form a sister clade to plant viruses of the family Geminiviridae. Ten genera are recognized in this family.

<i>Tupanvirus</i> Proposed genus of viruses

Tupanvirus is a genus of viruses first described in 2018. The genus is composed of two species of virus that are in the giant virus group. Researchers discovered the first isolate in 2012 from deep water sediment samples taken at 3,000 m depth off the coast of Brazil. The second isolate was collected from a soda lake in Southern Nhecolândia, Brazil in 2014. They are named after Tupã (Tupan), a Guaraní thunder god, and the places they were found. These are the first viruses reported to possess genes for amino-acyl tRNA synthetases for all 20 standard amino acids.

<i>Medusavirus</i> Type of virus

Medusavirus is a nucleocytoplasmic large DNA virus first isolated from a Japanese hot spring in 2019. It notably encodes all five types of histones — H1, H2A, H2B, H3, and H4 — which are involved in DNA packaging in eukaryotes, raising the possibility that they may have been involved in the origin of eukaryotes. The virus can harden amoebas of the species Acanthamoeba castellanii into stone-like cysts, but infection usually causes infected amoebas to burst open. The virus was named after Medusa, the monster in Greek mythology whose gaze turned people to stone.

<i>Smacoviridae</i> Family of viruses

Smacoviridae is a family of single-stranded DNA viruses. The genomes of this family are small. The name Smacoviridae stands for 'small circular genome virus'. The genomes are circular single-stranded DNA and encode rolling-circle replication initiation proteins (Rep) and unique capsid proteins. As of 2021, 12 genera and 84 species are recognized in this family. The viruses in this taxon were isolated from faecal samples from insects and vertebrates by metagenomic methods. Little is known about their biology.

References

  1. 1 2 Colson P, De Lamballerie X, Yutin N, Asgari S, Bigot Y, Bideshi DK, Cheng XW, Federici BA, Van Etten JL, Koonin EV, La Scola B, Raoult D (2013). ""Megavirales", a proposed new order for eukaryotic nucleocytoplasmic large DNA viruses". Archives of Virology. 158 (12): 2517–21. doi:10.1007/s00705-013-1768-6. PMC   4066373 . PMID   23812617.
  2. 1 2 3 4 5 "Virus Taxonomy: 2019 Release". talk.ictvonline.org. International Committee on Taxonomy of Viruses. Retrieved 25 April 2020.
  3. Koonin EV, Dolja VV, Krupovic M, Varsani A, Wolf YI, Yutin N, Zerbini M, Kuhn JH (October 2019). "Create a megataxonomic framework, filling all principal taxonomic ranks, for DNA viruses encoding vertical jelly roll-type major capsid proteins". ICTV Proposal (Taxoprop): 2019.003G. doi:10.13140/RG.2.2.14886.47684.
  4. Colson P, de Lamballerie X, Fournous G, Raoult D (2012). "Reclassification of giant viruses composing a fourth domain of life in the new order Megavirales". Intervirology. 55 (5): 321–332. doi: 10.1159/000336562 . PMID   22508375.
  5. Iyer, L. M.; Aravind, L.; Koonin, E. V. (December 2001). "Common Origin of Four Diverse Families of Large Eukaryotic DNA Viruses". Journal of Virology. 75 (23): 11720–34. doi:10.1128/JVI.75.23.11720-11734.2001. PMC   114758 . PMID   11689653.
  6. 1 2 3 4 Subramaniam, K (14 January 2020). "A New Family of DNA Viruses Causing Disease in Crustaceans from Diverse Aquatic Biomes". mBio. 11 (1). doi:10.1128/mBio.02938-19. PMC   6960288 . PMID   31937645. CC-BY icon.svg
  7. "Ascoviridae—Ascoviridae—dsDNA Viruses—International Committee on Taxonomy of Viruses (ICTV)". International Committee on Taxonomy of Viruses (ICTV). Archived from the original on December 8, 2017. Retrieved 2017-12-07.
  8. Asgari, Sassan; Bideshi, Dennis K; Bigot, Yves; Federici, Brian A; Cheng, Xiao-Wen (2017). "ICTV Virus Taxonomy Profile: Ascoviridae". The Journal of General Virology. 98 (1): 4–5. doi:10.1099/jgv.0.000677. PMC   5370392 . PMID   28218573.
  9. "African swine fever (ASF) | animal disease". Encyclopedia Britannica. Retrieved 2017-12-07.
  10. "Iridoviridae—Iridoviridae—dsDNA Viruses—International Committee on Taxonomy of Viruses (ICTV)". International Committee on Taxonomy of Viruses (ICTV). Retrieved 2017-12-07.
  11. Ke F, Zhang QY (April 2022). "ADRV 12L: A Ranaviral Putative Rad2 Family Protein Involved in DNA Recombination and Repair". Viruses. 14 (5): 908. doi: 10.3390/v14050908 . PMC   9146916 . PMID   35632650.
  12. Boyer, Mickaël; Yutin, Natalya; Pagnier, Isabelle; Barrassi, Lina; Fournous, Ghislain; Espinosa, Leon; Robert, Catherine; Azza, Saïd; Sun, Siyang (2009-12-22). "Giant Marseillevirus highlights the role of amoebae as a melting pot in emergence of chimeric microorganisms". Proceedings of the National Academy of Sciences of the United States of America. 106 (51): 21848–53. Bibcode:2009PNAS..10621848B. doi: 10.1073/pnas.0911354106 . PMC   2799887 . PMID   20007369.
  13. Aherfi, Sarah (2014-10-01). "The expanding family Marseilleviridae". Virology. 466–467: 27–37. doi: 10.1016/j.virol.2014.07.014 . ISSN   0042-6822. PMID   25104553.
  14. Arslan, Defne; Legendre, Matthieu; Seltzer, Virginie; Abergel, Chantal; Claverie, Jean-Michel (2011-10-18). "Distant Mimivirus relative with a larger genome highlights the fundamental features of Megaviridae". Proceedings of the National Academy of Sciences. 108 (42): 17486–91. Bibcode:2011PNAS..10817486A. doi: 10.1073/pnas.1110889108 . PMC   3198346 . PMID   21987820.
  15. 1 2 3 4 Lad SB, Upadhyay M, Thorat P, Nair D, Moseley GW, Srivastava S, Pradeepkumar PI, Kondabagil K (September 2023). "Biochemical Reconstitution of the Mimiviral Base Excision Repair Pathway". J Mol Biol. 435 (17): 168188. doi:10.1016/j.jmb.2023.168188. PMID   37380013.
  16. Fischer MG, Kelly I, Foster LJ, Suttle CA (October 2014). "The virion of Cafeteria roenbergensis virus (CroV) contains a complex suite of proteins for transcription and DNA repair". Virology. 466–467: 82–94. doi:10.1016/j.virol.2014.05.029. PMID   24973308.
  17. Schulz, Frederik; Yutin, Natalya; Ivanova, Natalia N.; Ortega, Davi R.; Lee, Tae Kwon; Vierheilig, Julia; Daims, Holger; Horn, Matthias; Wagner, Michael (2017-04-07). "Giant viruses with an expanded complement of translation system components" (PDF). Science. 356 (6333): 82–85. Bibcode:2017Sci...356...82S. doi:10.1126/science.aal4657. ISSN   0036-8075. PMID   28386012. S2CID   206655792., UCPMS ID: 1889607, PDF
  18. Koonin, EV; Krupovic, M; Yutin, N (2015). "Evolution of double-stranded DNA viruses of eukaryotes: from bacteriophages to transposons to giant viruses". Annals of the New York Academy of Sciences. 1341 (1): 10–24. Bibcode:2015NYASA1341...10K. doi:10.1111/nyas.12728. PMC   4405056 . PMID   25727355. Figure 3
  19. Yutin, Natalya; et al. (2013). "Mimiviridae: clusters of orthologous genes, reconstruction of gene repertoire evolution and proposed expansion of the giant virus family". Virology Journal. 10: 106. doi: 10.1186/1743-422X-10-106 . PMC   3620924 . PMID   23557328.
  20. Blog of Carolina Reyes, Kenneth Stedman: Are Phaeocystis globosa viruses (OLPG) and Organic Lake phycodnavirus a part of the Phycodnaviridae or Mimiviridae?, on ResearchGate, Jan. 8, 2016
  21. Maruyama, Fumito; Shoko (2016). "Evolution and Phylogeny of Large DNA Viruses, Mimiviridae and Phycodnaviridae Including Newly Characterized Heterosigma akashiwo Virus". Frontiers in Microbiology. 7: 1942. doi: 10.3389/fmicb.2016.01942 . PMC   5127864 . PMID   27965659.
  22. Zhang, W; Zhou, J; Liu, T; Yu, Y; Pan, Y; Yan, S; Wang, Y (2015). "Four novel algal virus genomes discovered from Yellowstone Lake metagenomes". Scientific Reports. 5: 15131. Bibcode:2015NatSR...515131Z. doi:10.1038/srep15131. PMC   4602308 . PMID   26459929. Figure 6
  23. Yong, Ed (2013). "Giant viruses open Pandora's box". Nature. doi:10.1038/nature.2013.13410. S2CID   88440241.
  24. Aherfi, Sarah; Colson, Philippe; La Scola, Bernard; Raoult, Didier (2016-03-22). "Giant Viruses of Amoebas: An Update". Frontiers in Microbiology. 7: 349. doi: 10.3389/fmicb.2016.00349 . ISSN   1664-302X. PMC   4801854 . PMID   27047465.
  25. "Biggest Virus Yet Found, May Be Fourth Domain of Life?". 2013-07-19. Archived from the original on July 21, 2013. Retrieved 2017-12-07.
  26. Wilson, W. H.; Van Etten, J. L.; Allen, M. J. (2009). "The Phycodnaviridae: The Story of How Tiny Giants Rule the World". Lesser Known Large dsDNA Viruses. Current Topics in Microbiology and Immunology. Vol. 328. pp. 1–42. doi:10.1007/978-3-540-68618-7_1. ISBN   978-3-540-68617-0. PMC   2908299 . PMID   19216434.
  27. Ornes, Stephen (2017-07-31). "Return of the giant zombie virus". Science News for Students. Retrieved 2017-12-07.
  28. "Pithovirus". viralzone.expasy.org. Retrieved 2017-12-07.
  29. Moss, Bernard (2013). "Poxvirus DNA Replication". Cold Spring Harbor Perspectives in Biology. 5 (9): a010199. doi:10.1101/cshperspect.a010199. PMC   3753712 . PMID   23838441.
  30. Needham, David M.; Yoshizawa, Susumu; Hosaka, Toshiaki; Poirier, Camille; Choi, Chang Jae; Hehenberger, Elisabeth; Irwin, Nicholas A. T.; Wilken, Susanne; Yung, Cheuk-Man; Bachy, Charles; Kurihara, Rika; Nakajima, Yu; Kojima, Keiichi; Kimura-Someya, Tomomi; Leonard, Guy; Malmstrom, Rex R.; Mende, Daniel R.; Olson, Daniel K.; Sudo, Yuki; Sudek, Sebastian; Richards, Thomas A.; DeLong, Edward F.; Keeling, Patrick J.; Santoro, Alyson E.; Shirouzu, Mikako; Iwasaki, Wataru; Worden, Alexandra Z. (8 October 2019). "A distinct lineage of giant viruses brings a rhodopsin photosystem to unicellular marine predators". Proceedings of the National Academy of Sciences. 116 (41): 20574–83. Bibcode:2019PNAS..11620574N. doi: 10.1073/pnas.1907517116 . PMC   6789865 . PMID   31548428.
  31. Karki, Sangita; Moniruzzaman, Mohammad; Aylward, Frank O. (2021). "Comparative Genomics and Environmental Distribution of Large dsDNA Viruses in the Family Asfarviridae". Frontiers in Microbiology. 12: 657471. doi: 10.3389/fmicb.2021.657471 . PMC   8005611 . PMID   33790885.
  32. Yoshikawa, Genki; Blanc-Mathieu, Romain; Song, Chihong; Kayama, Yoko; Mochizuki, Tomohiro; Murata, Kazuyoshi; Ogata, Hiroyuki; Takemura, Masaharu (2019). "Medusavirus, a novel large DNA virus discovered from hot spring water". Journal of Virology. 93 (8). doi:10.1128/JVI.02130-18. PMC   6450098 . PMID   30728258.
  33. Andreani, Julien; Khalil, Jacques Y. B.; Baptiste, Emeline; Hasni, Issam; Michelle, Caroline; Raoult, Didier; Levasseur, Anthony; La Scola, Bernard (22 January 2018). "Orpheovirus IHUMI-LCC2: A New Virus among the Giant Viruses". Frontiers in Microbiology. 8: 2643. doi: 10.3389/fmicb.2017.02643 . PMC   5786535 . PMID   29403444.
  34. Hauröder B, Wylezich C, Junglas L, Loch S, Eisenkolb J, Michel R (20 July 2018). "New Giant Virus in Free-Living Amoeba". Wiley Analytical Science. doi:10.1002/imaging.6224 (inactive 1 November 2024).{{cite magazine}}: CS1 maint: DOI inactive as of November 2024 (link)
  35. Bäckström D, Yutin N, Jørgensen SL, Dharamshi J, Homa F, Zaremba-Niedwiedzka K, Spang A, Wolf YI, Koonin EV, Ettema TJ (2019). "Virus genomes from deep sea sediments expand the ocean megavirome and support independent origins of viral gigantism". mBio. 10 (2): e02497-18. doi:10.1128/mBio.02497-18. PMC   6401483 . PMID   30837339.
  36. 1 2 Guglielmini, Julien; Woo, Anthony C.; Krupovic, Mart; Forterre, Patrick; Gaia, Morgan (2019-09-10). "Diversification of giant and large eukaryotic dsDNA viruses predated the origin of modern eukaryotes". Proceedings of the National Academy of Sciences. 116 (39): 19585–92. Bibcode:2019PNAS..11619585G. doi: 10.1073/pnas.1912006116 . PMC   6765235 . PMID   31506349.