Jump to content

Mimiviridae

From Wikipedia, the free encyclopedia
(Redirected from Megaviridae)

Mimiviridae
Tupanvirus
Virus classification Edit this classification
(unranked): Virus
Realm: Varidnaviria
Kingdom: Bamfordvirae
Phylum: Nucleocytoviricota
Class: Megaviricetes
Order: Imitervirales
Family: Mimiviridae
Subfamilies and genera

See text

Mimiviridae is a family of viruses. Amoeba and other protists serve as natural hosts. The family contains three subfamilies that contain nine genera.[1][2][3][4] Viruses in this family belong to the nucleocytoplasmic large DNA virus clade (NCLDV), also referred to as giant viruses.

History

[edit]

The first member of this family, Mimivirus, was discovered in 2003,[5] and the first complete genome sequence was published in 2004.[6] However, the mimivirus Cafeteria roenbergensis virus[7] was isolated and partially characterized in 1995,[8] although the host was misidentified at the time, and the virus was designated BV-PW1.[7]

Taxonomy

[edit]

The family contains the following subfamilies and genera (-virinae denotes subfamily and -virus denotes genus):[2]

Structure

[edit]
Ultrastructure of Bodo saltans virus particles and its replication[9]

Viruses in Mimiviridae have icosahedral and round geometries, with between T=972 and T=1141, or T=1200 symmetry. The diameter is around 400 nm, with a length of 125 nm. Genomes are linear and non-segmented, around 1200kb in length. The genome has 911 open reading frames.[1]

Life cycle

[edit]

Replication follows the DNA strand displacement model. DNA-templated transcription is the method of transcription. Amoeba serve as the natural host.[1]

Molecular biology

[edit]

Three putative DNA base excision repair enzymes were characterized from Mimivirus.[10] The base excision repair (BER) pathway was experimentally reconstituted using the purified recombinant proteins uracil-DNA glycosylase (mvUDG), AP endonuclease (mvAPE), and DNA polymerase X protein (mvPolX).[10] When reconstituted in vitro mvUDG, mvAPE and mvPolX function cohesively to repair uracil-containing DNA predominantly by long patch base excision repair, and thus these processes likely participate in the BER pathway early in the Mimivirus life cycle.[10]

Clinical

[edit]

Mimiviruses have been associated with pneumonia but their significance is currently unknown.[11] The only virus of this family isolated from a human to date is LBA 111.[12] At the Pasteur Institute of Iran (Tehran), researchers identified mimivirus DNA in bronchoalveolar lavage (BAL) and sputum samples of a child patient, utilizing real-time PCR (2018).  Analysis reported 99% homology of LBA111, lineage C of the Megavirus chilensis.[13] With only a few reported cases previous to this finding, the legitimacy of the mimivirus as an emerging infectious disease in humans remains controversial.[14][15]

Mimivirus has also been implicated in rheumatoid arthritis.[16]

See also

[edit]

References

[edit]
  1. ^ a b c "Viral Zone". ExPASy. Retrieved 15 June 2015.
  2. ^ a b "Virus Taxonomy: 2024 Release". International Committee on Taxonomy of Viruses. Retrieved 23 March 2025.
  3. ^ Schulz, Frederik; Yutin, Natalya; Ivanova, Natalia N.; Ortega, Davi R.; Lee, Tae Kwon; Vierheilig, Julia; Daims, Holger; Horn, Matthias; Wagner, Michael (7 April 2017). "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
  4. ^ Abrahão, Jônatas; Silva, Lorena; Silva, Ludmila Santos; Khalil, Jacques Yaacoub Bou; Rodrigues, Rodrigo; Arantes, Thalita; Assis, Felipe; Boratto, Paulo; Andrade, Miguel; Kroon, Erna Geessien; Ribeiro, Bergmann; Bergier, Ivan; Seligmann, Herve; Ghigo, Eric; Colson, Philippe; Levasseur, Anthony; Kroemer, Guido; Raoult, Didier; Scola, Bernard La (27 February 2018). "Tailed giant Tupanvirus possesses the most complete translational apparatus of the known virosphere". Nature Communications. 9 (1): 749. Bibcode:2018NatCo...9..749A. doi:10.1038/s41467-018-03168-1. PMC 5829246. PMID 29487281. Fig. 4 and §Discussion: "Considering that tupanviruses comprise a sister group to amoebal mimiviruses..."
  5. ^ Suzan-Monti, M; La Scola, B; Raoult, D (2006). "Genomic and evolutionary aspects of Mimivirus". Virus Res. 117 (1): 145–155. doi:10.1016/j.virusres.2005.07.011. PMID 16181700.
  6. ^ Raoult, D.; Audic, S; Robert, C; Abergel, C; Renesto, P; Ogata, H; La Scola, B; Suzan, M; Claverie, JM (2004). "The 1.2-Megabase Genome Sequence of Mimivirus". Science. 306 (5700): 1344–50. Bibcode:2004Sci...306.1344R. doi:10.1126/science.1101485. PMID 15486256. S2CID 84298461.
  7. ^ a b Matthias G. Fischer; Michael J. Allen; William H. Wilson; Curtis A. Suttle (2010). "Giant virus with a remarkable complement of genes infects marine zooplankton". Proceedings of the National Academy of Sciences. 107 (45): 19508–13. Bibcode:2010PNAS..10719508F. doi:10.1073/pnas.1007615107. PMC 2984142. PMID 20974979.
  8. ^ D.R. Garza; C.A. Suttle (1995). "Large double-stranded DNA viruses which cause the lysis of a marine heterotrophic nanoflagellate (Bodo sp.) occur in natural marine viral communities". Aquatic Microbial Ecology. 9 (3): 203–210. doi:10.3354/ame009203.
  9. ^ Deeg, C.M.; Chow, E.C.T.; Suttle, C.A. (2018). "The kinetoplastid-infecting Bodo saltans virus (BsV), a window into the most abundant giant viruses in the sea". eLife. 7: e33014. doi:10.7554/eLife.33014. PMC 5871332. PMID 29582753.
  10. ^ a b c Lad SB, Upadhyay M, Thorat P, Nair D, Moseley GW, Srivastava S, Pradeepkumar PI, Kondabagil K. Biochemical Reconstitution of the Mimiviral Base Excision Repair Pathway. J Mol Biol. 2023 Sep 1;435(17):168188. doi: 10.1016/j.jmb.2023.168188. Epub 2023 Jun 26. PMID 37380013
  11. ^ Saadi H, Pagnier I, Colson P, Cherif JK, Beji M, Boughalmi M, Azza S, Armstrong N, Robert C, Fournous G, La Scola B, Raoult D (August 2013). "First isolation of Mimivirus in a patient with pneumonia". Clin. Infect. Dis. 57 (4): e127–34. doi:10.1093/cid/cit354. PMID 23709652.
  12. ^ Yoosuf N, Pagnier I, Fournous G, Robert C, La Scola B, Raoult D, Colson P (April 2014). "Complete genome sequence of Courdo11 virus, a member of the family Mimiviridae". Virus Genes. 48 (2): 218–23. doi:10.1007/s11262-013-1016-x. PMID 24293219. S2CID 12038772.
  13. ^ Sakhaee, Fatemeh; Vaziri, Farzam; Bahramali, Golnaz; Davar Siadat, Seyed; Fateh, Abolfazl (October 2020). "Pulmonary Infection Related to Mimivirus in Patient with Primary Ciliary Dyskinesia". Emerging Infectious Diseases. 26 (10): 2524–2526. doi:10.3201/eid2610.191613. PMC 7510730. PMID 32946733.
  14. ^ La Scola, Bernard; Marrie, Thomas J.; Auffray, Jean-Pierre; Raoult, Didier (March 2005). "Mimivirus in pneumonia patients". Emerging Infectious Diseases. 11 (3): 449–452. doi:10.3201/eid1103.040538. PMC 3298252. PMID 15757563.
  15. ^ Saadi, Hanene; Pagnier, Isabelle; Colson, Philippe; Kanoun Cherif, Jouda; Beji, Majed; Boughalmi, Mondher; Azza, Saïd; Armstrong, Nicholas; Robert, Catherine; Fournous, Ghislain; La Scola, Bernard (24 May 2013). "First isolation of Mimivirus in a patient with pneumonia". Clinical Infectious Diseases. 57 (4): e127 – e134. doi:10.1093/cid/cit354. PMID 23709652 – via Oxford Academic.
  16. ^ Shah, N.; Hulsmeier, A. J.; Hochhold, N.; Neidhart, M.; Gay, S.; Hennet, T. (2013). "Exposure to Mimivirus Collagen Promotes Arthritis". Journal of Virology. 88 (2): 838–45. doi:10.1128/JVI.03141-13. PMC 3911627. PMID 24173233.
[edit]