DNA virus

From Wikipedia, the free encyclopedia
Jump to: navigation, search


Group I: dsDNA viruses[edit]

HHV-6 genome



Orders within this group are defined on the basis of morphology rather than DNA sequence similarity. It is thought that morphology is more conserved in this group than sequence similarity or gene order which is extremely variable. Three orders and 31 families are currently recognised. A fourth order—Megavirales—for the nucleocytoplasmic large DNA viruses has been proposed.[1] Four genera are recognised that have not yet been assigned a family.




A recently proposed clade is the Megavirales which includes the nucleocytoplasmic large DNA viruses.[1][3] This proposal has yet to be ratified by the ICTV.

The virophages are a group of viruses that infect other viruses. Their classification has yet to be decided. A family Lavidaviridae has been proposed for the genera Mavirus and Sputnikvirus.[4]

Host range[edit]


Species of the order Ligamenvirales and the families Ampullaviridae, Bicaudaviridae, Clavaviridae, Fuselloviridae, Globuloviridae, Guttaviridae and Turriviridae infect hyperthermophilic archaea species of the Crenarchaeota.




Species of the family Nimaviridae infect crustaceans.


Species of the family Plasmaviridae infect species of the class Mollicutes.

Species of the family Pandoraviridae infect amoebae.






A group known as the pleolipoviruses, although having a similar genome organisation, differ in having either single or double stranded DNA genomes.[5] Within the double stranded forms have runs of single stranded DNA.[6] These viruses have been placed in the family Pleolipoviridae.[7]

These viruses are nonlytic and form virions characterized by a lipid vesicle enclosing the genome.[8] They do not have nucleoproteins. The lipids in the viral membrane are unselectively acquired from host cell membranes. The virions contain two to three major structural proteins, which either are embedded in the membrane or form spikes distributed randomly on the external membrane surface.

This group includes the following viruses:

Group II: ssDNA viruses[edit]

Genome of bacteriophage ΦX174, a single-stranded DNA virus

Although bacteriophages were first described in 1927, it was only in 1959 that Sinshemer working with phage Phi X 174 showed that they could possess single-stranded DNA genomes.[9][10] Despite this discovery until relatively recently it was believed that the majority of DNA viruses belonged to the double-stranded clade. Recent work suggests that this may not be the case with single-stranded viruses forming the majority of viruses found in sea water, fresh water, sediment, terrestrial, extreme, metazoan-associated and marine microbial mats.[11][12] Many of these "environmental" viruses belong to the family Microviridae.[13] However, the vast majority has yet to be classified and assigned to genera and higher taxa. Because most of these viruses do not appear to be related or are only distantly related to known viruses additional taxa will be created for these.


Families in this group have been assigned on the basis of the nature of the genome (circular or linear) and the host range. Eleven families are currently recognised.


A division of the circular single stranded viruses into four types has been proposed.[14] This division seems likely reflects their phylogenetic relationships.





Given the variety of single stranded viruses that have been described this scheme—if it is accepted by the ICTV—will need to be extended.

Host range[edit]


Molecular biology[edit]

All viruses in this group require formation of a replicative form—a double stranded DNA intermediate—for genome replication. This is normally created from the viral DNA with the assistance of the host's own DNA polymerase.

Recently classified viruses[edit]

In the 9th edition of the viral taxonomy of the ICTV (published 2011) the Bombyx mori densovirus type 2 was placed in a new family—the Bidnaviridae on the basis of its genome structure and replication mechanism. This is currently the only member of this family but it seems likely that other species will be allocated to this family in the near future.

A new genus—Bufavirus—was proposed on the basis of the isolation of two new viruses from human stool.[15] These viruses have since been renamed Primate protoparvovirus and been placed in the genus Protoparvovirus.[16][17] Another member of this genus—megabat bufavius 1—has been reported from bats.[18]


The most recently introduced family of ssDNA viruses is the Genomoviridae (the family name is an acronym derived from geminivirus-like, no movement protein).[19] The type species of the genus Gemycircularvirus within the family is a fungus-infecting virus Sclerotinia sclerotiorum hypovirulence associated DNA virus 1.[20] The name Gemycircularvirus stands for Gemini-like myco-infecting circular virus.[21] The Genomoviridae family includes many as of yet unclassified ssDNA viruses discovered using metagenomic approaches.[19]

Unclassified ssDNA viruses

An unrelated group of ssDNA viruses, also discovered using viral metagenomics, includes the species bovine stool associated circular virus and chimpanzee stool associated circular virus.[22] The closest relations to this genus appear to be the Nanoviridae but further work will be needed to confirm this. Another isolate that appears to be related to these viruses has been isolated from pig faeces in New Zealand.[23] This isolate also appears to be related to the pig stool-associated single-stranded DNA virus. This virus has two large open reading frames one encoding the capsid gene and the other the Rep gene. These are bidirectionally transcribed and separated by intergenic regions. Another virus of this group has been reported again from pigs.[24] Some of this group of viruses may infect fungi.[25] A virus from this group has been isolated from turkey faeces.[26] Another ten viruses from this group have been isolated from pig faeces.[27] Additional viruses from this group have been reported from dragonflies and damselflies.[28] Viruses that appear to belong to this group have been isolated from other mammals including cows, rodents, bats, badgers and foxes.[25] A isolate from this group has also been identified in a child with encephalitis.[29] The genomes in this group have some similarity with the Sclerotinia sclerotiorum hypovirulence associated DNA virus 1 which infects fungi. Another virus from this group has been isolated from mosquitoes.[30] Viruses from this group have also been isolaed from the blood of HIV+ve patients.[31] Viruses in this group have also been isolated from other cases of encephalitis, diarrhoea and sewage.[32] Isolates from this group have also been isolated from the cerebrospinal fluid and brains of patients with multiple sclerosis.[33] Two additional viruses that may belong to this group are Ostrich faecal associated ssDNA virus and Rabbit faecal associated ssDNA virus. Three viruses in this group have been isolated from plants.[34] Another virus has been isolated from birds.[35]

Unassigned species[edit]


Animal viruses—vertebrates

Among these are the parvovirus-like viruses. These have linear single-stranded DNA genomes but unlike the parvoviruses the genome is bipartate. This group includes the Bombyx mori densovirus type 2, Hepatopancreatic parvo-like virus and Lymphoidal parvo-like virus. A new family Bidensoviridae has been proposed for this group but this proposal has not been ratified by the ICTV to date.[36] Their closest relations appear to be the Brevidensoviruses (family Parvoviridae).[37]

Fur seal feces-associated circular DNA virus was isolate from the faeces of a fur seal (Arctocephalus forsteri) in New Zealand.[38] The genome has 2 main open reading frames and is 2925 nucleotides in length. Another virus porcine stool associated virus 4[39] has been isolated that appears to be related to the fur seal virus.

Two viruses have been isolated from human faeces—circo-like virus-Brazil hs1 and hs2—with genome lengths of 2526 and 2533 nucleotides respectively.[40] These viruses have four open reading frames. These viruses appear to be related to three viruses previously isolated from waste water, a bat and from a rodent.[41] This appears to belong to a novel group.

Two viruses have been described from the nesting material yellow crowned parakeet (Cyanoramphus auriceps)—Cyanoramphus nest-associated circular X virus (2308 nt) and Cyanoramphus nest-associated circular K virus (2087 nt)[42] Both viruses have two bidirectional open reading frames. Within these are the rolling-circle replication motifs I, II, III and the helicase motifs Walker A and Walker B. There is also a conserved nonanucleotide motif required for rolling-circle replication. CynNCKV has some similarity to the picobiliphyte nano-like virus (Picobiliphyte M5584-5)[43] and CynNCXV has some similarity to the rodent stool associated virus (RodSCV M-45).[44]

Psittacine beak and feather disease virus is a single stranded circular molecule of 1993 nucleotide bases encoding seven open reading frames—three in the virion strand and four in the complementary strand.[45] The open reading frames have some homology to porcine circovirus, subterranean clover stunt virus and faba bean necrotic yellows virus.

A virus with a circular genomesea turtle tornovirus 1—has been isolated from a sea turtle with fibropapillomatosis.[46] It is sufficiently unrelated to any other known virus that it may belong to a new family. The closest relations seem to be the Gyrovirinae. The proposed genus name for this virus is Tornovirus.

Animal viruses—invertebrates

A virus—Acheta domesticus volvovirus has been isolated from the house cricket (Acheta domesticus).[47] The genome is circular, has four open reading frames and is 2,517 nucleotides in length. It appears to be unrelated to previously described species. The genus name Volvovirus has been proposed for these species.[48] The genomes in this genus are ~2.5 nucleotides in length and encode 4 open reading frames.

Two new viruses have been isolated from the copepods Acartia tonsa and Labidocera aestivaAcartia tonsa copepod circo-like virus and Labidocera aestiva copepod circo-like virus respectively.


An unusual—and as yet unnamed—virus has been isolated from the flatwom Girardia tigrina.[50] Because of its genome organisation, this virus appears to belong to an entirely new family. It is the first virus to be isolated from a flatworm.

From the hepatopancreas of the shrimp (Farfantepenaeus duorarum) a circular single stranded DNA virus has been isolated.[51] This virus does not appear to cause disease in the shrimp.

A circo-like virus has been isolated from the shrimp (Penaeus monodon).[52] The 1,777-nucleotide genome is circular and single stranded. It has some similarity to the circoviruses and cycloviruses.

Ten new circular viruses have been isolated from dragonfly larvae.[53] The genomes range from 1628 to 2668 nucleotides in length.

Ten viruses have been isolated from echinoderms.[54] All appear to belong to as yet undescribed genera.


A virus—Cassava associated circular DNA virus—that has some similarity to Sclerotinia sclerotiorum hypovirulence associated DNA virus 1 has been isolated.[55]

A circular single stranded DNA virus has been isolated from a grapevine.[56] This species may be related to the family Geminiviridae but differs from this family in a number of important respects including genome size.


A virus— Euphorbia caput medusae latent virus —is so divergent from the other members of the geminiviruses that a new genus has been proposed for it.[58] The name of this new genus is proposed to be Capulavirus. Another virus in this genus is Alfalfa leaf curl virus.[59]

Several viruses—baminivirus, nepavirus and niminivirus—related to geminvirus have also been reported.[25]

A virus - Ancient caribou feces associated virus - has been cloned from 700-y-old caribou faeces.[60]


Although ~50 archaeal viruses are known, all but two have double stranded genomes. The first archaeal ssDNA virus to be isolated is the Halorubrum pleomorphic virus 1, which has a pleomorphic enveloped virion and a circular genome.[61] This virus has now been placed in the family Pleolipoviridae.

The second single stranded DNA virus infecting Archaea is Aeropyrum coil-shaped virus (ACV).[62] The genome is circular and with 24,893 nucleotides is currently the largest known ssDNA genome. The viron is nonenveloped, hollow, cylindrical and formed from a coiling fiber. The morphology and the genome appear to be unique.

The new family Spiraviridae (from Latin spira, "a coil") has been created by the ICTV to accommodate ACV.

Marine and other

Several hundred single stranded DNA viral genomes have been isolated from seawater.[63] Their hosts have yet to be identified but are likely to be eukaryotic phytoplankton and zooplankton. They fall into at least 11 distinct groups that are unrelated to previously described viral families.

A virus—Boiling Springs Lake virus—appears to have evolved by a recombination event between a DNA virus (circovirus) and an RNA virus (tombusvirus).[64] The genome is circular and encodes two proteins—a Rep protein and a capsid protein.


A new virus has been isolated from the diatom Chaetoceros setoensis.[66] It has a single stranded DNA genome and does not appear to be a member of any previously described group.

Satellite viruses[edit]

Satellite viruses are small viruses with either RNA or DNA as their genomic material that require another virus to replicate. There are two types of DNA satellite viruses—the alphasatellites and the betasatellites—both of which are dependent on begomoviruses. At present satellite viruses are not classified into genera or higher taxa.


Phylogenetic relationships[edit]


Phylogenetic relationships between these families are difficult to determine. The genomes differ significantly in size and organisation. Most studies that have attempted to determine these relationships are based either on some of the more conserved proteins—DNA polymerase and others—or on common structural features. In general most of the proposed relationships are tentative and have not yet been used by the ICTV in their classification.

ds DNA viruses[edit]

Herpesviruses and caudoviruses


While the three families in the order Herpesvirales are clearly related on morphological grounds, it has proven difficult to determine the dates of divergence between them because of the lack of gene conservation.[67] On morphological grounds they appear to be related to the bacteriophages—specifically the Caudoviruses.

The branching order among the herpesviruses suggests that Alloherpesviridae is the basal clade and that Herpesviridae and Malacoherpesviridae are sister clades.[68] Given the phylogenetic distances between vertebrates and molluscs this suggests that herpesviruses were initially fish viruses and that they have evolved with their hosts to infect other vertebrates.

The vertebrate herpesviruses initially evolved ~400 million years ago and underwent subsequent evolution on the supercontinent Pangaea.[69] The alphaherpesvirinae separated from the branch leading to the betaherpesvirinae and gammaherpesvirinae about 180 million years ago to 220 million years ago.[70] The avian herpes viruses diverged from the branch leading to the mammalian species.[71] The mammalian species divided into two branches—the Simplexvirus and Varicellovirus genera. This latter divergence appears to have occurred around the time of the mammalian radiation.


A common origin for the herpesviruses and the caudoviruses has been suggested on the basis of parallels in their capsid assembly pathways and similarities between their portal complexes, through which DNA enters the capsid.[74] These two groups of viruses share a distinctive 12-fold arrangement of subunits in the portal complex. A second paper has suggested an evolutionary relationship between these two groups of viruses.[73]

It seems likely that the tailed viruses infecting the archaea are also related to the tailed viruses infecting bacteria.[75][76]

Large DNA viruses

The family Ascoviridae appear to have evolved from the Iridoviridae.[77] The family Polydnaviridae may have evolved from the Ascoviridae. Molecular evidence suggests that the Phycodnaviridae may have evolved from the family Iridoviridae.[78] These four families (Ascoviridae, Iridoviridae, Phycodnaviridae and Polydnaviridae) may form a clade but more work is needed to confirm this.


Based on the analysis of the DNA polymerase the genus Dinodnavirus may be a member of the family Asfarviridae.[80] Further work on this virus will required before a final assignment can be made.

The nucleocytoplasmic large DNA virus group (Asfarviridae, Iridoviridae, Marseilleviridae, Mimiviridae, Phycodnaviridae and Poxviridae) along with three other families—Adenoviridae, Cortiviridae and Tectiviridae—and the phage Sulfolobus turreted icosahedral virus and the satellite virus Sputnik all possess double β-barrel major capsid proteins suggesting a common origin.[81]

Some of the relations among the large viruses have been established.[82] Mimiviruses are distantly related to Phycodnaviridae. Pandoraviruses share a common ancestor with Coccolithoviruses within the Phycodnaviridae family.[83]

Pithoviruses are related to Iridoviridae and Marseilleviridae.

Other viruses


The families Adenoviridae and Tectiviridae appear to be related structurally.[84]

Baculoviruses evolved from the nudiviruses 310 million years ago.[85][86]


The Nimaviridae may be related to nudiviruses and baculoviruses.[88]

The Nudiviruses seem to be related to the polydnaviruses.[89]




The polymerases from the archaea are similar to family B DNA Pols. The T4-like viruses infect both bacteria and archaea[93] and their pol gene resembles that of eukaryotes. The DNA polymerase of mitochondria resembles that of the T odd phages (Myoviridae).[94]

The virophage—Mavirus—may have evolved from a recombination between a transposon of the Polinton (Maverick) family and an unknown virus.[95]

The polyoma and papillomaviruses appear to have evolved from single-stranded DNA viruses and ultimately from plasmids.[73]

ss DNA viruses[edit]


Capsid proteins of most icosahedral ssRNA and ssDNA viruses display the same structural fold, the eight-stranded beta-barrel, also known as the jelly-roll fold. On the other hand, the replication proteins of icosahedral ssDNA viruses belong to the superfamily of rolling-circle replication initiation proteins that are commonly found in prokaryotic plasmids.[97] Based on these observations, it has been proposed that small DNA viruses have originated via recombination between RNA viruses and plasmids.[98][99]

Circoviruses may have evolved from a nanovirus.[100][101][102]

Given the similarities between the rep proteins of the alphasatellites and the nanoviruses, it is likely that the alphasatellites evolved from the nanoviruses.[103] Further work in this area is needed to clarify this.

The geminiviruses may have evolved from phytoplasmal plasmids.[104]

Based on the three-dimensional structure of the Rep proteins the geminiviruses and parvoviruses may be related.[105]

The ancestor of the geminiviruses probably infected dicots.[58]

The parvoviruses have frequently invaded the germ lines of diverse animal species including mammals, fishes, birds, tunicates, arthropods and flatworms.[106][107] In particular they have been associated with the human genome for ~98 million years.

Members of the family Bidnaviridae have evolved from insect parvoviruses by replacing the typical replication-initiation endonuclease with a protein-primed family B DNA polymerase acquired from large DNA transposons of the Polinton/Maverick family. Some bidnavirus genes were also horizontally acquired from reoviruses (dsRNA genomes) and baculoviruses (dsDNA genomes).[108]

Bacteriophage evolution[edit]


The vast majority (96.3%) are tailed with and only 230 (3.7%) are polyhedral, filamentous or pleomorphic. The family Siphoviridae is the largest family (>3600 descriptions: 57.3%). The tailed phages appear to be monophyletic and are the oldest known virus group.[110] They arose repeatedly in different hosts and there are at least 11 separate lines of descent.


A putative course of evolution of these phages has been proposed by Ackermann.[111]






The asfarviruses, iridoviruses, mimiviruses, phycodnaviruses and poxviruses have been shown to belong to a single group,[112]—the large nuclear and cytoplasmic DNA viruses. These are also abbreviated "NCLDV".[113] This clade can be divided into two groups:

  • the poxvirus-asfarviruses group.


The evolution of this group of viruses appears to be complex with genes having been gained from multiple sources.[114] It has been proposed that the ancestor of NCLDVs has evolved from large, virus-like DNA transposons of the Polinton/Maverick family.[115] From Polinton/Maverick transposons NCLDVs might have inherited the key components required for virion morphogenesis, including the major and minor capsid proteins, maturation protease and genome packaging ATPase.[116]

Another group of large viruses—the Pandoraviridae—has been described. Two species—Pandoravirus salinus and Pandoravirus dulcis—have been recognized. These were isolated from Chile and Australia respectively. These viruses are about one micrometer in diameter making them one of the largest viruses discovered so far. Their gene complement is larger than any other known virus to date. At present they appear to be unrelated to any other species of virus.[117]

An even larger genus, Pithovirus, has since been discovered, measuring about 1.5 µm in length.[118] Another virus - Cedratvirus - may be related this group.[119]


  1. ^ a b 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): 321–32. doi:10.1159/000336562. PMID 22508375. 
  2. ^ Simoliūnas E, Kaliniene L, Truncaitė L, Zajančkauskaitė A, Staniulis J, Kaupinis A, Ger M, Valius M, Meškys R, et al. (2013). "Klebsiella phage vB_KleM-RaK2—A giant singleton virus of the family Myoviridae". PLoS ONE. 8 (4): e60717. doi:10.1371/journal.pone.0060717. PMC 3622015Freely accessible. PMID 23593293. 
  3. ^ Colson P, De Lamballerie X, Yutin N, et al. (December 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 4066373Freely accessible. PMID 23812617. 
  4. ^ Krupovic M, Kuhn JH, Fischer MG (2016). "A classification system for virophages and satellite viruses". Arch Virol. 161 (1): 233–247. doi:10.1007/s00705-015-2622-9. PMID 26446887. 
  5. ^ Pietilä MK, Atanasova NS, Manole V, Liljeroos L, Butcher SJ, Oksanen HM, Bamford DH (2012). "Virion Architecture Unifies Globally Distributed Pleolipoviruses Infecting Halophilic Archaea". Journal of Virology. 86 (9): 5067–79. doi:10.1128/JVI.06915-11. PMC 3347350Freely accessible. PMID 22357279. 
  6. ^ Sencilo A, Paulin L, Kellner S, Helm M, Roine E (2012). "Related haloarchaeal pleomorphic viruses contain different genome types". Nucleic Acids Res. 40 (12): 5523–34. doi:10.1093/nar/gks215. PMC 3384331Freely accessible. PMID 22396526. 
  7. ^ Pietilä MK, Roine E, Sencilo A, Bamford DH, Oksanen HM (2016). "Pleolipoviridae, a newly proposed family comprising archaeal pleomorphic viruses with single-stranded or double-stranded DNA genomes". Arch Virol. 161 (1): 249–256. doi:10.1007/s00705-015-2613-x. PMID 26459284. 
  8. ^ Pietilä MK, Atanasova NS, Manole V, Liljeroos L, Butcher SJ, Oksanen HM, Bamford DH (2012). "Virion architecture unifies globally distributed pleolipoviruses infecting halophilic archaea". J Virol. 86 (9): 5067–79. doi:10.1128/JVI.06915-11. PMC 3347350Freely accessible. PMID 22357279. 
  9. ^ Sinshemer RL (1959). "Purification and properties of bacteriophage φX174". Journal of Molecular Biology. 1: 37–IN5. doi:10.1016/S0022-2836(59)80005-X. 
  10. ^ Sinshemer RL (1959). "A single-stranded deoxyribonucleic acid from bacteriophage φX174". Journal of Molecular Biology. 1: 43–IN6. doi:10.1016/S0022-2836(59)80006-1. 
  11. ^ Desnues C, Rodriguez-Brito B, Rayhawk S, Kelley S, Tran T, Haynes M, Liu H, Furlan M, Wegley L, Chau B, Ruan Y, Hall D, Angly FE, Edwards RA, Li L, Thurber RV, Reid RP, Siefert J, Souza V, Valentine DL, Swan BK, Breitbart M, Rohwer F (2008). "Biodiversity and biogeography of phages in modern stromatolites and thrombolites". Nature. 452 (7185): 340–3. doi:10.1038/nature06735. PMID 18311127. 
  12. ^ Angly FE, Felts B, Breitbart M, Salamon P, Edwards RA, Carlson C, Chan AM, Haynes M, Kelley S, Liu H, Mahaffy JM, Mueller JE, Nulton J, Olson R, Parsons R, Rayhawk S, Suttle CA, Rohwer F (2006). "The marine viromes of four oceanic regions". PLoS Biol. 4 (11): e368. doi:10.1371/journal.pbio.0040368. PMC 1634881Freely accessible. PMID 17090214. 
  13. ^ Roux S, Krupovic M, Poulet A, Debroas D, Enault F (2012). "Evolution and diversity of the Microviridae viral family through a collection of 81 new complete genomes assembled from virome reads". PLoS ONE. 7 (7): e40418. doi:10.1371/journal.pone.0040418. PMC 3394797Freely accessible. PMID 22808158. 
  15. ^ Phan TG, Vo NP, Bonkoungou IJ, Kapoor A, Barro N, O'Ryan M, Kapusinszky B, Wang C, Delwart E (2012). "Acute diarrhea in West-African children: diverse enteric viruses and a novel parvovirus genus". J Virol. 86 (20): 11024–30. doi:10.1128/JVI.01427-12. PMC 3457132Freely accessible. PMID 22855485. 
  16. ^ "ICTV Official Taxonomy: Updates since the 8th Report". ICTV Official Taxonomy. ICTV Official Taxonomy. Retrieved 11 June 2014. 
  17. ^ Cotmore SF, Agbandje-McKenna M, Chiorini JA, Mukha DV, Pintel DJ, Qiu J, Soderlund-Venermo M, Tattersall P, Tijssen P, Gatherer D, Davison AJ (2014). "The family Parvoviridae". Arch. Virol. 159 (5): 1239–47. doi:10.1007/s00705-013-1914-1. PMC 4013247Freely accessible. PMID 24212889. 
  18. ^ Sasaki M, Gonzalez G, Wada Y, Setiyono A, Handharyani E, Rahmadani I, Taha S, Adiani S, Latief M, Kholilullah ZA, Subangkit M, Kobayashi S, Nakamura I, Kimura T, Orba Y, Ito K, Sawa H (2016). "Divergent bufavirus harboured in megabats represents a new lineage of parvoviruses". Sci Rep. 6: 24257. doi:10.1038/srep24257. PMC 4845017Freely accessible. PMID 27113297. 
  19. ^ a b Krupovic M, Ghabrial SA, Jiang D, Varsani A (2016). "Genomoviridae: a new family of widespread single-stranded DNA viruses". Arch Virol. 161 (9): 2633–2643. doi:10.1007/s00705-016-2943-3. PMID 27343045. 
  20. ^ Yu X, Li B, Fu Y, Jiang D, Ghabrial SA, Li G, Peng Y, Xie J, Cheng J, Huang J, Yi X (2010). "A geminivirus-related DNA mycovirus that confers hypovirulence to a plant pathogenic fungus". Proc Natl Acad Sci USA. 107 (18): 8387–92. doi:10.1073/pnas.0913535107. PMC 2889581Freely accessible. PMID 20404139. 
  21. ^ Rosario K, Dayaram A, Marinov M, Ware J, Kraberger S, Stainton D, Breitbart M, Varsani A (2012). "Diverse circular ssDNA viruses discovered in dragonflies (Odonata: Epiprocta)". J Gen Virol. 93 (12): 2668–81. doi:10.1099/vir.0.045948-0. PMID 22915694. 
  22. ^ Blinkova O, Victoria J, Li Y, Keele BF, Sanz C, Ndjango JB, Peeters M, Travis D, Lonsdorf EV, Wilson ML, Pusey AE, Hahn BH, Delwart EL (2010). "Novel circular DNA viruses in stool samples of wild-living chimpanzees". J Gen Virol. 91 (Pt 1): 74–86. doi:10.1099/vir.0.015446-0. PMC 2887567Freely accessible. PMID 19759238. 
  23. ^ Sikorski A, Argüello-Astorga GR, Dayaram A, Dobson RC, Varsani A (2012). "Discovery of a novel circular single-stranded DNA virus from porcine faeces". Arch Virol. 158 (1): 283–9. doi:10.1007/s00705-012-1470-0. PMID 22972681. 
  24. ^ Kim AR, Chung HC, Kim HK, Kim EO, Nguyen VG, Choi MG, Yang HJ, Kim JA, Park BK (February 2014). "Characterization of a complete genome of a circular single-stranded DNA virus from porcine stools in Korea". Virus Genes. 48 (1): 81–8. doi:10.1007/s11262-013-1003-2. PMID 24170425. 
  25. ^ a b c Sikorski A, Massaro M, Kraberger S, Young LM, Smalley D, Martin DP, Varsani A (2013). "Novel myco-like DNA viruses discovered in the faecal matter of various animals". Virus Res. 177 (2): 209–216. doi:10.1016/j.virusres.2013.08.008. PMID 23994297. 
  26. ^ Reuter G, Boros A, Delwart E, Pankovics P (2014). "Novel circular single-stranded DNA virus from turkey faeces". Arch Virol. 159 (8): 2161–4. doi:10.1007/s00705-014-2025-3. PMID 24562429. 
  27. ^ Cheung AK, Ng TF, Lager KM, Alt DP, Delwart E, Pogranichniy RM (2015). "Identification of several clades of novel single-stranded circular DNA viruses with conserved stem-loop structures in pig feces". Arch. Virol. 160 (1): 353–8. doi:10.1007/s00705-014-2234-9. PMID 25248627. 
  28. ^ Dayaram A, Potter KA, Pailes R, Marinov M, Rosenstein DD, Varsani A (2015). "Identification of diverse circular single-stranded DNA viruses in adult dragonflies and damselflies (Insecta: Odonata) of Arizona and Oklahoma, USA". Infect Genet Evol. 30: 278–287. doi:10.1016/j.meegid.2014.12.037. PMID 25577985. 
  29. ^ Zhou C, Zhang S, Gong Q, Hao A (2015). "A novel gemycircularvirus in an unexplained case of child encephalitis". Virol. J. 12: 197. doi:10.1186/s12985-015-0431-0. PMC 4657213Freely accessible. PMID 26596706. 
  30. ^ Li W, Gu Y, Shen Q, Yang S, Wang X, Wan Y, Zhang W (2015). "A novel gemycircularvirus from experimental rats". Virus Genes. 51 (2): 302–5. doi:10.1007/s11262-015-1238-1. PMID 26303898. 
  31. ^ Uch R, Fournier PE, Robert C, Blanc-Tailleur C, Galicher V, Barre R, Jordier F, de Micco P, Raoult D, Biagini P (2015). "Divergent Gemycircularvirus in HIV-positive blood, France". Emerg Infect Dis. 21 (11): 2096–8. doi:10.3201/eid2111.150486. PMC 4622245Freely accessible. PMID 26488181. 
  32. ^ Phan TG, Mori D, Deng X, Rajindrajith S, Ranawaka U, Fan Ng TF, Bucardo-Rivera F, Orlandi P, Ahmed K, Delwart E (2015). "Small circular single stranded DNA viral genomes in unexplained cases of human encephalitis, diarrhea, and in untreated sewage". Virology. 482: 98–104. doi:10.1016/j.virol.2015.03.011. PMC 4461510Freely accessible. PMID 25839169. 
  33. ^ Lamberto I, Gunst K, Müller H, Zur Hausen H, de Villiers EM (2014). "Mycovirus-like DNA virus sequences from cattle serum and human brain and serum samples from multiple sclerosis patients". Genome Announc. 2 (4): e00848–14. doi:10.1128/genomeA.00848-14. PMC 4148726Freely accessible. PMID 25169858. 
  34. ^ Male MF, Kami V, Kraberger S, Varsani A (2015). "Genome sequences of Poaceae-associated Gemycircularviruses from the Pacific Ocean island of Tonga". Genome Announc. 3 (5): e01144–15. doi:10.1128/genomeA.01144-15. PMC 4611678Freely accessible. PMID 26472826. 
  35. ^ Hanna ZR, Runckel C, Fuchs J, DeRisi JL, Mindell DP, Van Hemert C, Handel CM, Dumbacher JP (2015). "Isolation of a complete circular virus genome sequence from an Alaskan black-capped chickadee (Poecile atricapillus) gastrointestinal tract sample". Genome Announc. 3 (5): e01081–15. doi:10.1128/genomeA.01081-15. PMC 4582580Freely accessible. PMID 26404604. 
  36. ^ Tijssen P, Bergoin M (1995). "Densonucleosis viruses constitute an increasingly diversified subfamily among the parvoviruses". Seminars in Virology. 6 (5): 347–355. doi:10.1006/smvy.1995.0041. 
  37. ^ Sukhumsirichart W, Attasart P, Boonsaeng V, Panyim S (2006). "Complete nucleotide sequence and genomic organization of hepatopancreatic parvovirus (HPV) of Penaeus monodon". Virology. 346 (2): 266–277. doi:10.1016/j.virol.2005.06.052. PMID 16356523. 
  38. ^ Sikorski A, Dayaram A, Varsani A (2013). "Identification of a Novel Circular DNA Virus in New Zealand Fur Seal (Arctocephalus forsteri) Fecal Matter". Genome Announc. 1 (4): e00558–13. doi:10.1128/genomeA.00558-13. PMC 3738887Freely accessible. PMID 23929471. 
  39. ^ Cheung, A. K.; Ng, T. F.-f.; Lager, K. M.; Alt, D. P.; Delwart, E. L.; Pogranichniy, R. M. (2014). "Unique Circovirus-Like Genome Detected in Pig Feces". Genome Announcements. 2 (2): e00251–14. doi:10.1128/genomeA.00251-14. ISSN 2169-8287. PMC 3983299Freely accessible. PMID 24723710. 
  40. ^ Castrignano SB, Nagasse-Sugahara TK, Kisielius JJ, Ueda-Ito M, Brandão PE, Curti SP (December 2013). "Two novel circo-like viruses detected in human feces: complete genome sequencing and electron microscopy analysis". Virus Res. 178 (2): 364–73. doi:10.1016/j.virusres.2013.09.018. PMID 24055464. 
  41. ^ Cheung AK, Ng TF, Lager KM, Alt DP, Delwart EL, Pogranichniy RM (2014). "Identification of a novel single-stranded circular DNA virus in pig feces". Genome Announc. 2 (2): e00347–14. doi:10.1128/genomeA.00347-14. PMC 4007987Freely accessible. PMID 24786952. 
  42. ^ Sikorski A, Kearvell J, Elkington S, Dayaram A, Argüello-Astorga GR, Varsani A (2013). "Novel ssDNA viruses discovered in yellow-crowned parakeet (Cyanoramphus auriceps) nesting material". Arch Virol. 158 (7): 1603–7. doi:10.1007/s00705-013-1642-6. PMID 23417396. 
  43. ^ Yoon HS, Price DC, Stepanauskas R, Rajah VD, Sieracki ME, Wilson WH, Yang EC, Duffy S, Bhattacharya D, et al. (2011). "Single-cell genomics reveals organismal interactions in uncultivated marine protists". Science. 332 (6030): 714–7. doi:10.1126/science.1203163. PMID 21551060. 
  44. ^ Phan TG, Kapusinszky B, Wang C, Rose RK, Lipton HL, Delwart EL (2011). "The fecal viral flora of wild rodents". PLoS Pathog. 7 (9): e1002218. doi:10.1371/journal.ppat.1002218. PMC 3164639Freely accessible. PMID 21909269. 
  45. ^ Bassami MR, Berryman D, Wilcox GE, Raidal SR (1998). "Psittacine beak and feather disease virus nucleotide sequence analysis and its relationship to porcine circovirus, plant circoviruses, and chicken anaemia virus". Virology. 249 (2): 453–9. doi:10.1006/viro.1998.9324. PMID 9791035. 
  46. ^ Ng TF, Manire C, Borrowman K, Langer T, Ehrhart L, Breitbart M (2009). "Discovery of a novel single-stranded DNA virus from a sea turtle fibropapilloma by using viral metagenomics". J Virol. 83 (6): 2500–9. doi:10.1128/JVI.01946-08. PMC 2648252Freely accessible. PMID 19116258. 
  47. ^ Pham HT, Bergoin M, Tijssen P (2013). "Acheta domesticus volvovirus, a novel single-stranded circular DNA virus of the house cricket". Genome Announc. 1 (2): e0007913. doi:10.1128/genomeA.00079-13. PMC 3623006Freely accessible. PMID 23516206. 
  48. ^ Pham HT, Iwao H, Bergoin M, Tijssen P (2013). "New Volvovirus Isolates from Acheta domesticus (Japan) and Gryllus assimilis (United States)". Genome Announc. 1 (3): e00328–13. doi:10.1128/genomeA.00328-13. PMC 3675518Freely accessible. PMID 23792751. 
  49. ^ Dayaram A, Goldstien S, Zawar-Reza P, Gomez C, Harding JS, Varsani A (2013). "whose replication associated protein (Rep) shares similarities with Rep-like sequences of bacterial origin". J Gen Virol. 94 (Pt 5): 1104–10. doi:10.1099/vir.0.050088-0. PMID 23364192. 
  50. ^ Rebrikov DV, Bulina ME, Bogdanova EA, Vagner LL, Lukyanov SA (2002). "Complete genome sequence of a novel extrachromosomal virus-like element identified in planarian Girardia tigrina". BMC Genomics. 13 (1): 15. doi:10.1186/1471-2164-3-15. PMC 3269984Freely accessible. PMID 22233149. 
  51. ^ Ng TF, Alavandi S, Varsani A, Burghart S, Breitbart M (2013). "Metagenomic identification of a nodavirus and a circular ssDNA virus in semi-purified viral nucleic acids from the hepatopancreas of healthy Farfantepenaeus duorarum shrimp". Dis Aquat Organ. 105 (3): 237–42. doi:10.3354/dao02628. PMID 23999707. 
  52. ^ Pham HT, Yu Q, Boisvert M, Van HT, Bergoin M, Tijssen P (2014). "A circo-like virus isolated from Penaeus monodon shrimps". Genome Announc. 2 (1): e01172–13. doi:10.1128/genomeA.01172-13. PMC 3894284Freely accessible. PMID 24435870. 
  53. ^ Dayaram A, Galatowitsch M, Harding JS, Argüello-Astorga GR, Varsani A (March 2014). "Novel circular DNA viruses identified in Procorduliagrayi and Xanthocnemiszealandica larvae using metagenomic approaches". Infect Genet Evol. 22: 134–41. doi:10.1016/j.meegid.2014.01.013. PMID 24462907. 
  54. ^ Jackson EW, Bistolas KS, Button JB, Hewson I (2016). "Novel Circular Single-Stranded DNA Viruses among an Asteroid, Echinoid and Holothurian (Phylum: Echinodermata)". PLOS ONE. 11 (11): e0166093. doi:10.1371/journal.pone.0166093. PMC 5113903Freely accessible. PMID 27855181. 
  55. ^ Dayaram A, Opong A, Jäschke A, Hadfield J, Baschiera M, Dobson RC, Offei SK, Shepherd DN, Martin DP, Varsani A (2012). "Molecular characterisation of a novel cassava associated circular ssDNA virus". Virus Res. 166 (1–2): 130–5. doi:10.1016/j.virusres.2012.03.009. PMID 22465471. 
  56. ^ Krenz B, Thompson JR, Fuchs M, Perry KL (2012). "Complete genome sequence of a new circular DNA virus from grapevine". J Virol. 86 (14): 7715. doi:10.1128/JVI.00943-12. PMC 3416304Freely accessible. PMID 22733880. 
  57. ^ Al Rwahnih M, Dave A, Anderson MM, Rowhani A, Uyemoto JK, Sudarshana M (October 2013). "Association of a DNA virus with grapevines affected by red blotch disease in California". Phytopathology Phytopathology. 103 (10): 1069–76. doi:10.1094/PHYTO-10-12-0253-R. PMID 23656312. 
  58. ^ a b Bernardo P, Golden M, Akram M, et al. (October 2013). "Identification and characterisation of a highly divergent geminivirus: evolutionary and taxonomic implications". Virus Res. 177 (1): 35–45. doi:10.1016/j.virusres.2013.07.006. PMID 23886668. 
  59. ^ Roumagnac P, Granier M, Bernardo P, Deshoux M, Ferdinand R, Galzi S, Fernandez E, Julian C, Abt I, Filloux D, Mesléard F, Varsani A, Blanc S, Martin DP, Peterschmitt M (2015). "Alfalfa Leaf Curl Virus: an Aphid-Transmitted Geminivirus". J. Virol. 89 (18): 9683–8. doi:10.1128/JVI.00453-15. PMC 4542355Freely accessible. PMID 26109720. 
  60. ^ Ng TF, Chen LF, Zhou Y, Shapiro B, Stiller M, Heintzman PD, Varsani A, Kondov NO, Wong W, Deng X, Andrews TD, Moorman BJ, Meulendyk T, MacKay G, Gilbertson RL, Delwart E (2014). "Preservation of viral genomes in 700-y-old caribou feces from a subarctic ice patch". Proc. Natl. Acad. Sci. U.S.A. 111 (47): 16842–7. doi:10.1073/pnas.1410429111. PMC 4250163Freely accessible. PMID 25349412. 
  61. ^ Pietilä MK, Laurinavicius S, Sund J, Roine E, Bamford DH (2010). "The single-stranded DNA genome of novel archaeal virus Halorubrum pleomorphic virus 1 is enclosed in the envelope decorated with glycoprotein spikes". J Virol. 84 (2): 788–798. doi:10.1128/JVI.01347-09. PMC 2798366Freely accessible. PMID 19864380. 
  62. ^ Mochizuki T, Krupovic M, Pehau-Arnaudet G, Sako Y, Forterre P, Prangishvili D (2012). "Archaeal virus with exceptional virion architecture and the largest single-stranded DNA genome". Proc Natl Acad Sci U S A. 109 (33): 13386–91. doi:10.1073/pnas.1203668109. PMC 3421227Freely accessible. PMID 22826255. 
  63. ^ Labonté JM, Suttle CA (November 2013). "Previously unknown and highly divergent ssDNA viruses populate the oceans". ISME J. 7 (11): 2169–77. doi:10.1038/ismej.2013.110. PMC 3806263Freely accessible. PMID 23842650. 
  64. ^ Diemer GS, Stedman KM (2012). "A novel virus genome discovered in an extreme environment suggests recombination between unrelated groups of RNA and DNA viruses". Biology Direct. 7 (1): 13. doi:10.1186/1745-6150-7-13. PMC 3372434Freely accessible. PMID 22515485. 
  65. ^ Roux S, Enault F, Bronner G, Vaulot D, Forterre P, Krupovic M (2013). "Chimeric viruses blur the borders between the major groups of eukaryotic single-stranded DNA viruses". Nat Commun. 4: 2700. doi:10.1038/ncomms3700. PMID 24193254. 
  66. ^ Tomaru Y, Toyoda K, Suzuki H, Nagumo T, Kimura K, Takao Y (2013). "New single-stranded DNA virus with a unique genomic structure that infects marine diatom Chaetoceros setoensis". Sci Rep. 3: 3337. doi:10.1038/srep03337. PMC 3840382Freely accessible. PMID 24275766. 
  68. ^ Davison AJ (2010). "Herpesvirus systematics". Vet Microbiol. 143 (1–2): 52–69. doi:10.1016/j.vetmic.2010.02.014. PMC 2995426Freely accessible. PMID 20346601. 
  70. ^ McGeoch DJ, Cook S, Dolan A, Jamieson FE, Telford EA (1995). "Molecular phylogeny and evolutionary timescale for the family of mammalian herpesviruses". J Mol Biol. 247 (3): 443–458. doi:10.1006/jmbi.1995.0152. PMID 7714900. 
  72. ^ Davison AJ (2002). "Evolution of the herpesviruses". Veterinary microbiology. 86 (1–2): 69–88. doi:10.1016/S0378-1135(01)00492-8. PMID 11888691. 
  73. ^ a b c Koonin EV, Krupovic M, Yutin N (2015). "Evolution of double-stranded DNA viruses of eukaryotes: from bacteriophages to transposons to giant viruses". Ann. N. Y. Acad. Sci. 1341: 10–24. doi:10.1111/nyas.12728. PMC 4405056Freely accessible. PMID 25727355. 
  74. ^ Baker ML, Jiang W, Rixon FJ, Chiu W (2005). "Common ancestry of herpesviruses and tailed DNA bacteriophages". J. Virol. 79 (23): 14967–70. doi:10.1128/JVI.79.23.14967-14970.2005. PMC 1287596Freely accessible. PMID 16282496. 
  75. ^ Krupovic M, Forterre P, Bamford DH (2010). "Comparative analysis of the mosaic genomes of tailed archaeal viruses and proviruses suggests common themes for virion architecture and assembly with tailed viruses of bacteria". J Mol Biol. 397 (1): 144–160. doi:10.1016/j.jmb.2010.01.037. PMID 20109464. 
  76. ^ Senčilo A, Jacobs-Sera D, Russell DA, Ko CC, Bowman CA, Atanasova NS, Österlund E, Oksanen HM, Bamford DH, Hatfull GF, Roine E, Hendrix RW (2013). "Snapshot of haloarchaeal tailed virus genomes". RNA Biol. 10 (5): 803–816. doi:10.4161/rna.24045. PMC 3737338Freely accessible. PMID 23470522. 
  78. ^ Wilson WH, Van Etten JL, Allen MJ (2009). "The Phycodnaviridae: the story of how tiny giants rule the world". Curr Top Microbiol Immunol. Current Topics in Microbiology and Immunology. 328: 1–42. doi:10.1007/978-3-540-68618-7_1. ISBN 978-3-540-68617-0. PMC 2908299Freely accessible. PMID 19216434. 
  79. ^ Prangishvili D, Garrett RA (2004). "Exceptionally diverse morphotypes and genomes of crenarchaeal hyperthermophilic viruses". Biochem Soc Trans. 32 (Pt 2): 204–8. doi:10.1042/BST0320204. PMID 15046572. 
  80. ^ Ogata H, Toyoda K, Tomaru Y, Nakayama N, Shirai Y, Claverie JM, Nagasaki K (2009). "Remarkable sequence similarity between the dinoflagellate-infecting marine girus and the terrestrial pathogen African swine fever virus". Virol J. 6 (1): 178. doi:10.1186/1743-422X-6-178. PMC 2777158Freely accessible. PMID 19860921. 
  81. ^ Krupovic M, Bamford DH (2008). "Virus evolution: how far does the double beta-barrel viral lineage extend?". Nature Reviews Microbiology. 6 (12): 941–8. doi:10.1038/nrmicro2033. PMID 19008892. 
  82. ^ Yutin N, Wolf YI, Koonin EV (2014). "Origin of giant viruses from smaller DNA viruses not from a fourth domain of cellular life". Virology. 466–467: 38–52. doi:10.1016/j.virol.2014.06.032. PMC 4325995Freely accessible. PMID 25042053. 
  83. ^ Yutin N, Koonin EV (2013). "Pandoraviruses are highly derived phycodnaviruses". Biol. Direct. 8: 25. doi:10.1186/1745-6150-8-25. PMC 3924356Freely accessible. PMID 24148757. 
  84. ^ Benson SD, Bamford JK, Bamford DH, Burnett RM (1999). "Viral evolution revealed by bacteriophage PRD1 and human adenovirus coat protein structures". Cell. 98 (6): 825–833. doi:10.1016/S0092-8674(00)81516-0. PMID 10499799. 
  85. ^ Thézé J, Bézier A, Periquet G, Drezen JM, Herniou EA (2011). "Paleozoic origin of insect large dsDNA viruses". Proc Natl Acad Sci USA. 108 (38): 15931–5. doi:10.1073/pnas.1105580108. PMC 3179036Freely accessible. PMID 21911395. 
  86. ^ Wang Y, Jehle JA (2009). "Nudiviruses and other large, double-stranded circular DNA viruses of invertebrates: new insights on an old topic". J Invertebr Pathol. 101 (3): 187–193. doi:10.1016/j.jip.2009.03.013. PMID 19460388. 
  90. ^ Keller J, Leulliot N, Cambillau C, Campanacci V, Porciero S, Prangishvilli D, Forterre P, Cortez D, Quevillon-Cheruel S, van Tilbeurgh H (2007). "Crystal structure of AFV3-109, a highly conserved protein from crenarchaeal viruses". Virol J. 4: 12. doi:10.1186/1743-422X-4-12. PMC 1796864Freely accessible. PMID 17241456. 
  91. ^ Knopf CW (1998). "Evolution of viral DNA-dependent DNA polymerases". Virus Genes. 16 (1): 47–58. doi:10.1023/A:1007997609122. PMID 9562890. 
  92. ^ Villarreal LP, DeFilippis VR (2000). "A hypothesis for DNA viruses as the origin of eukaryotic replication proteins". J Virol. 74 (15): 7079–84. doi:10.1128/JVI.74.15.7079-7084.2000. PMC 112226Freely accessible. PMID 10888648. 
  93. ^ Zillig W, Prangishvilli D, Schleper C, Elferink M, Holz I, Albers S, Janekovic D, Götz D (1996). "Viruses, plasmids and other genetic elements of thermophilic and hyperthermophilic Archaea". FEMS Microbiol Rev. 18 (2–3): 225–236. doi:10.1111/j.1574-6976.1996.tb00239.x. PMID 8639330. 
  94. ^ Shutt TE, Gray MW (2005). "Bacteriophage origins of mitochondrial replication and transcription proteins". Trends Genet. 22 (2): 90–95. doi:10.1016/j.tig.2005.11.007. PMID 16364493. 
  95. ^ Yutin, Natalya; Raoult, Didier; Koonin, Eugene V (2013). "Virophages, polintons, and transpovirons: a complex evolutionary network of diverse selfish genetic elements with different reproduction strategies". Virology Journal. 10 (1): 158. doi:10.1186/1743-422X-10-158. ISSN 1743-422X. PMC 3671162Freely accessible. PMID 23701946. 
  96. ^ Delwart E, Li L (2012). "Rapidly expanding genetic diversity and host range of the Circoviridae viral family and other Rep encoding small circular ssDNA genomes.". Virus Research. 164 (1–2): 114–121. doi:10.1016/j.virusres.2011.11.021. PMC 3289258Freely accessible. PMID 22155583. 
  97. ^ Ilyina TV, Koonin EV (1992). "Conserved sequence motifs in the initiator proteins for rolling circle DNA replication encoded by diverse replicons from eubacteria, eucaryotes and archaebacteria". Nucleic Acids Res. 20 (13): 3279–85. doi:10.1093/nar/20.13.3279. PMC 312478Freely accessible. PMID 1630899. 
  98. ^ Krupovic M (2012). "Recombination between RNA viruses and plasmids might have played a central role in the origin and evolution of small DNA viruses". BioEssays. 34 (10): 867–870. doi:10.1002/bies.201200083. PMID 22886750. 
  99. ^ Krupovic M (2013). "Networks of evolutionary interactions underlying the polyphyletic origin of ssDNA viruses". Curr Opin Virol. 3 (5): 578–586. doi:10.1016/j.coviro.2013.06.010. PMID 23850154. 
  100. ^ Gibbs MJ, Weiller GF (1999). "Evidence that a plant virus switched hosts to infect a vertebrate and then recombined with a vertebrate-infecting virus". Proc Natl Acad Sci USA. 96 (14): 8022–7. doi:10.1073/pnas.96.14.8022. PMC 22181Freely accessible. PMID 10393941. 
  101. ^ Meehan BM, Creelan JL, McNulty MS, Todd D (1997). "Sequence of porcine circovirus DNA: affinities with plant circoviruses". J Gen Virol. 78 (Pt 1): 221–7. doi:10.1099/0022-1317-78-1-221. PMID 9010307. 
  102. ^ Niagro FD, Forsthoefel AN, Lawther RP, Kamalanathan L, Ritchie BW, Latimer KS, Lukert PD (1998). "Beak and feather disease virus and porcine circovirus genomes: intermediates between the geminiviruses and plant circoviruses". Arch Virol. 143 (9): 1723–44. doi:10.1007/s007050050412. PMID 9787657. 
  103. ^ Xie Y, Wu P, Liu P, Gong H, Zhou X (2010). "Characterization of alphasatellites associated with monopartite begomovirus/betasatellite complexes in Yunnan, China". Virol J. 7 (1): 178. doi:10.1186/1743-422X-7-178. PMC 2922188Freely accessible. PMID 20678232. 
  104. ^ Krupovic M, Ravantti JJ, Bamford DH (2009). "Geminiviruses: a tale of a plasmid becoming a virus" (PDF). BMC Evol Biol. 9 (1): 112. doi:10.1186/1471-2148-9-112. PMC 2702318Freely accessible. PMID 19460138. 
  105. ^ Gronenborn B (2004). "Nanoviruses: genome organisation and protein function". Vet Microbiol. 98 (2): 103–9. doi:10.1016/j.vetmic.2003.10.015. PMID 14741122. 
  106. ^ Belyi VA, Levine AJ, Skalka AM (2010). "Sequences from ancestral single-stranded DNA viruses in vertebrate genomes: the parvoviridae and circoviridae are more than 40 to 50 million years old". J Virol. 84 (23): 12458–62. doi:10.1128/JVI.01789-10. PMC 2976387Freely accessible. PMID 20861255. 
  107. ^ Liu H, Fu Y, Xie J, Cheng J, Ghabrial SA, Li G, Peng Y, Yi X, Jiang D (2011). "Widespread endogenization of Densoviruses and Parvoviruses in animal and human genomes". J Virol. 85 (19): 9863–76. doi:10.1128/JVI.00828-11. PMC 3196449Freely accessible. PMID 21795360. 
  108. ^ Krupovic M, Koonin EV (2014). "Evolution of eukaryotic single-stranded DNA viruses of the Bidnaviridae family from genes of four other groups of widely different viruses". Scientific Reports. 4: 5347. doi:10.1038/srep05347. PMC 4061559Freely accessible. PMID 24939392. 
  109. ^ Ackermann HW, Prangishvili D (2012). "Prokaryote viruses studied by electron microscopy". Arch Virol. 157 (10): 1843–9. doi:10.1007/s00705-012-1383-y. PMID 22752841. 
  110. ^ Ackermann HW (2003). "Bacteriophage observations and evolution". Res Microbiol. 154 (4): 245–251. doi:10.1016/S0923-2508(03)00067-6. PMID 12798228. 
  111. ^ Ackermann HW (1998). "Tailed bacteriophages: the order caudovirales". Adv Virus Res. Advances in Virus Research. 51: 135–201. doi:10.1016/S0065-3527(08)60785-X. ISBN 9780120398515. PMID 9891587. 
  113. ^ Yutin N, Wolf YI, Raoult D, Koonin EV (2009). "Eukaryotic large nucleo-cytoplasmic DNA viruses: clusters of orthologous genes and reconstruction of viral genome evolution". Virol. J. 6 (1): 223. doi:10.1186/1743-422X-6-223. PMC 2806869Freely accessible. PMID 20017929. 
  114. ^ Yutin N, Koonin EV (2012). "Hidden evolutionary complexity of Nucleo-Cytoplasmic Large DNA viruses of eukaryotes". Virol J. 9 (1): 161. doi:10.1186/1743-422X-9-161. PMC 3493329Freely accessible. PMID 22891861. 
  115. ^ Krupovic M, Koonin EV (2015). "Polintons: a hotbed of eukaryotic virus, transposon and plasmid evolution". Nat Rev Microbiol. 13 (2): 105–115. doi:10.1038/nrmicro3389. PMID 25534808. 
  116. ^ Krupovic M, Bamford DH, Koonin EV (2014). "Conservation of major and minor jelly-roll capsid proteins in Polinton (Maverick) transposons suggests that they are bona fide viruses". Biol Direct. 9: 6. doi:10.1186/1745-6150-9-6. PMC 4028283Freely accessible. PMID 24773695. 
  117. ^ Pennisi, E. (2013). "Ever-Bigger Viruses Shake Tree of Life". Science. 341 (6143): 226–7. doi:10.1126/science.341.6143.226. PMID 23868995. 
  119. ^ Andreani J, Aherfi S, Bou Khalil JY, Di Pinto F, Bitam I, Raoult D, Colson P, La Scola B (2016). "Cedratvirus, a double-cork structured giant virus, is a distant relative of Pithoviruses". Viruses. 8 (11): 300. doi:10.3390/v8110300. PMC 5127014Freely accessible. PMID 27827884. 

Additional reading[edit]