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Coronavirus

This page is about the type of many different viruses. For the current outbreak of the SARS-CoV-2, see COVID-19 pandemic.

Coronaviruses are a group of RNA viruses.[5][6] They cause diseases in birds and mammals, including humans. These diseases can be mild, or they can be fatal. In humans and birds, they cause respiratory tract infections. Mild illnesses in humans include some cases of the common cold (which is also caused by other viruses, for example rhinoviruses). More lethal varieties can cause SARS, MERS, and COVID-19.

Orthocoronavirinae
File:Coronaviruses 004 lores.jpg
Transmission electron micrograph of Avian coronavirus
File:2019-nCoV-CDC-23312 without background.png
Illustration of a SARS-CoV-2 virion[2]     Red: spike proteins (S)     Grey: lipid bilayer envelope     Yellow: envelope proteins (E)     Orange: membrane proteins (M)
Virus classification e
Unrecognized taxon (fix): Orthocoronavirinae
Genera[1]
Synonyms[3][4]
  • Coronavirinae

They are enveloped viruses with a positive-sense RNA genome.[7] The genome size of coronaviruses is about 26 to 32 kilobases,[8] which is extraordinarily large for an RNA virus. There are four major groups of coronaviruses, called alpha, beta, gamma, and delta.

The most famous coronavirus is one of the betas, the kind that causes Coronavirus disease 2019 (COVID-19) in humans.

The name "coronavirus" comes from the Latin word corona, meaning "crown" or "halo", and refers to how virions look under an electron microscopy (E.M.).[9] They have a fringe of large, bulbous surface projections looking like a crown. This morphology is created by the viral spike (S) peplomer, which are proteins on the surface of the virus. They decide which cells the virus can infect.

Proteins of coronaviruses are the spike (S), envelope (E), membrane (M), and nucleocapsid (N).

Diseases

Coronaviruses infect the upper respiratory and gastrointestinal tracts of mammals and birds. Six different strains of coronaviruses infect humans. These include:

Coronaviruses are believed to cause many common colds in human adults. The significance and economic impact of coronaviruses is hard to assess. Unlike rhinoviruses (another common cold virus), human coronaviruses are easy to grow in the laboratory.

Structure

File:Vaccines-08-00587-g002-A.png
Structure of a coronavirus

Coronaviruses are large, spherical particles with unique surface projections.[10] Their size is variable, averageing 80 to 120 nms.[11] The total molecular weight is on average 40,000 kDa. They are enclosed in an envelope studded with projecting protein molecules.[12] These layers protect the virus when it is outside the host cell.[13]

The viral envelope is made up of a lipid bilayer in which the membrane (M), envelope (E), and spike (S) structural proteins are anchored.[14] The ratio of E:S:M in the lipid bilayer is approximately 1:20:300.[15] The E and M protein are the structural proteins that combined with the lipid bilayer to shape the viral envelope and maintain its size. S proteins are needed for interaction with the host cells. But human coronavirus NL63 is peculiar in that its M protein has the binding site for the host cell, and not its S protein.[16] The diameter of the envelope is 85 nm.

History

The earliest reports of a coronavirus infection in animals occurred in the late 1920s, when an acute respiratory infection of domesticated chickens happened in North America.[17] Arthur Schalk and M.C. Hawn in 1931 made the first detailed report which described a new respiratory infection of chickens in North Dakota. It was not realized at the time that three related viruses were involved.[18]

Human coronaviruses were discovered in the 1960's using two different methods.[19][20][21] E.C. Kendall, Malcolm Bynoe, and David Tyrrel, working at the Common Cold Unit of the British Medical Research Council, collected a unique common cold virus B814 in 1961.[22][23][24] The virus could not be cultivated using the techniques which had successfully cultivated rhinoviruses, adenoviruses, and other known common cold viruses. Eventually, this was solved.[25] The new cultivating method was introduced to the lab by Bertil Hoorn.[26] The isolated virus, when put into the noses of volunteers, caused a cold. The virus was inactivated by ether which showed it had a lipid envelope.[22][27][28] The novel virus caused a cold in volunteers and, like B814, was inactivated by ether.[29]

File:TEM of coronavirus OC43.jpg
Transmission electron micrograph of organ cultured coronavirus OC43

Scottish virologist June Almeida at St Thomas' Hospital, London, compared the structures of IBV, B814, and 229E in 1967.[30][31] Using transmission electron microscopy,the three viruses were shown to be similar in shape and have club-like spikes.[32] A research group at the National Institute of Health the same year isolated another member of this group of viruses.[33] Like B814, 229E, and IBV, the novel cold virus OC43 had distinctive club-like spikes when observed with the electron microscope.[34][35]

The IBV-like novel cold viruses looked like the mouse hepatitis virus. This new group of viruses were called "coronaviruses" from their crown-like appearance.[36][37] The coronavirus strain B814 was lost. It is not known which present human coronavirus it was.[38] Other human coronaviruses have since been identified, including SARS-CoV in 2003, HCoV NL63 in 2003, HCoV HKU1 in 2004, MERS-CoV in 2013, and SARS-CoV-2 in 2019.[39] There have been a large number of animal coronaviruses identified since the 1960s.

Coronavirus Media

  • TEM of avian infectious bronchitis virus rotated cropped.jpg

    Colorized transmission electron micrograph of coronavirus 229E

  • SARS-CoV MERS-CoV genome organization and S-protein domains.png

    Diagram of the genome and functional domains of the S protein for SARS-CoV and MERS-CoV

  • 15010 2020 1486 Fig3 HTML.webp

    After binding of the ACE2 receptor, SARS-CoV spike is activated and cleaved at the S1/S2 level.

  • SARS Coronavirus Genome Organization.png

    SARS-CoV genome and proteins

  • Coronavirus replication.png

    The life cycle of a coronavirus

  • Replication-transcription complex for Coronaviruses cropped.png

    Replicase-transcriptase complex

  • Transcription of nested mRNAs.jpg

    Transcription of nested mRNAs

  • Nested subgenomic RNA.jpg

    Nested set of subgenomic mRNAs

Related pages

References

  1. ↑ "Virus Taxonomy: 2018b Release". International Committee on Taxonomy of Viruses (ICTV). March 2019. Archived from the original on 4 March 2018. Retrieved 24 January 2020.
  2. ↑ "The Spiky Blob Seen Around the World". The New York Times. 1 April 2020. https://www.nytimes.com/2020/04/01/health/coronavirus-illustration-cdc.html. Retrieved 6 April 2020. 
  3. ↑ "2017.012-015S" (xlsx). International Committee on Taxonomy of Viruses (ICTV). October 2018. Archived from the original on 14 May 2019. Retrieved 24 January 2020.
  4. ↑ "ICTV Taxonomy history: Orthocoronavirinae". International Committee on Taxonomy of Viruses (ICTV). Archived from the original on 25 January 2020. Retrieved 24 January 2020.
  5. ↑ de Groot R.J. (2012). "Family Coronaviridae". In King A.M.Q. ' (ed.). Ninth Report of the International Committee on Taxonomy of Viruses. Elsevier, Oxford. pp. 806–828. ISBN 978-0-12-384684-6.
  6. ↑ International Committee on Taxonomy of Viruses. "ICTV Master Species List 2009 – v10". Archived from the original (xls) on 2013-04-15. Retrieved 2020-03-06.
  7. ↑ enveloped = has viral envelopes covering their protective protein capsids; positive sense = the RNA sequence may be directly translated into the desired viral proteins.
  8. ↑ One kilobase = 1000 base pairs
  9. ↑ virion = complete virus particle.
  10. ↑ Lua error in Module:Citation/CS1/Identifiers at line 630: attempt to index field 'known_free_doi_registrants_t' (a nil value).
  11. ↑ Lua error in Module:Citation/CS1/Identifiers at line 630: attempt to index field 'known_free_doi_registrants_t' (a nil value).
  12. ↑ Lalchhandama K (2020). "The chronicles of coronaviruses: the electron microscope, the doughnut, and the spike". Science Vision. 20 (2): 78–92. doi:10.33493/scivis.20.02.03.
  13. ↑ Lua error in Module:Citation/CS1/Identifiers at line 630: attempt to index field 'known_free_doi_registrants_t' (a nil value).
  14. ↑ Lai MM, Cavanagh D (1997). "The molecular biology of coronaviruses". Advances in Virus Research. 48: 1–100. doi:10.1016/S0065-3527(08)60286-9. ISBN 9780120398485. PMC 7130985. PMID 9233431.
  15. ↑ Lua error in Module:Citation/CS1/Identifiers at line 630: attempt to index field 'known_free_doi_registrants_t' (a nil value).
  16. ↑ Lua error in Module:Citation/CS1/Identifiers at line 630: attempt to index field 'known_free_doi_registrants_t' (a nil value).
  17. ↑ Lua error in Module:Citation/CS1/Identifiers at line 630: attempt to index field 'known_free_doi_registrants_t' (a nil value).
  18. ↑ "Il était une fois les coronavirus" (in fr-FR). Réalités Biomédicales. 2020-03-27. https://www.lemonde.fr/blog/realitesbiomedicales/2020/03/27/il-etait-une-fois-les-coronavirus. Retrieved 2020-04-18. 
  19. ↑ Kahn JS, McIntosh K (November 2005). "History and recent advances in coronavirus discovery". The Pediatric Infectious Disease Journal. 24 (11 Suppl): S223–7, discussion S226. doi:10.1097/01.inf.0000188166.17324.60. PMID 16378050.
  20. ↑ Mahase E (April 2020). "The BMJ in 1965". BMJ. 369: m1547. doi:10.1136/bmj.m1547. PMID 32299810.
  21. ↑ Lua error in Module:Citation/CS1/Identifiers at line 630: attempt to index field 'known_free_doi_registrants_t' (a nil value).
  22. ↑ 22.0 22.1 Lua error in Module:Citation/CS1/Identifiers at line 630: attempt to index field 'known_free_doi_registrants_t' (a nil value).
  23. ↑ Lua error in Module:Citation/CS1/Identifiers at line 630: attempt to index field 'known_free_doi_registrants_t' (a nil value).
  24. ↑ Lua error in Module:Citation/CS1/Identifiers at line 630: attempt to index field 'known_free_doi_registrants_t' (a nil value).
  25. ↑ Lua error in Module:Citation/CS1/Identifiers at line 630: attempt to index field 'known_free_doi_registrants_t' (a nil value).
  26. ↑ Tyrrell DA, Fielder M (2002). Cold Wars: The Fight Against the Common Cold. Oxford University Press. pp. 93–95. ISBN 978-0-19-263285-2.
  27. ↑ Hagan WA, Bruner DW, Gillespie JH, Timoney JF, Scott FW, Barlough JE (1988). Hagan and Bruner's Microbiology and Infectious Diseases of Domestic Animals. Cornell University Press. p. 440. ISBN 978-0-8014-1896-9.
  28. ↑ Knapp, Alex. "The secret history of The first coronavirus". Forbes. Retrieved 2020-05-06.
  29. ↑ Lua error in Module:Citation/CS1/Identifiers at line 630: attempt to index field 'known_free_doi_registrants_t' (a nil value).
  30. ↑ The woman who discovered the first coronavirus. Apr 14, 2020. https://www.bbc.com/news/uk-scotland-52278716. Retrieved May 13, 2022. 
  31. ↑ Lua error in Module:Citation/CS1/Identifiers at line 630: attempt to index field 'known_free_doi_registrants_t' (a nil value).
  32. ↑ Almeida JD, Tyrrell DA (April 1967). "The morphology of three previously uncharacterized human respiratory viruses that grow in organ culture". The Journal of General Virology. 1 (2): 175–8. doi:10.1099/0022-1317-1-2-175. PMID 4293939.
  33. ↑ McIntosh K, Becker WB, Chanock RM (December 1967). "Growth in suckling-mouse brain of "IBV-like" viruses from patients with upper respiratory tract disease". Proceedings of the National Academy of Sciences of the United States of America. 58 (6): 2268–73. Bibcode:1967PNAS...58.2268M. doi:10.1073/pnas.58.6.2268. PMC 223830. PMID 4298953.
  34. ↑ McIntosh K, Dees JH, Becker WB, Kapikian AZ, Chanock RM (April 1967). "Recovery in tracheal organ cultures of novel viruses from patients with respiratory disease". Proceedings of the National Academy of Sciences of the United States of America. 57 (4): 933–40. Bibcode:1967PNAS...57..933M. doi:10.1073/pnas.57.4.933. PMC 224637. PMID 5231356.
  35. ↑ Times, Harold M. Schmeck Jr Special To the New York (1967-05-05). "Six newly discovered viruses may explain cold: strains are similar to germ that causes a bronchial infection in chickens believed to be new group" (in en-US). The New York Times. ISSN 0362-4331 . https://www.nytimes.com/1967/05/05/archives/six-newly-discovered-viruses-may-explain-cold-strains-are-similar.html. Retrieved 2020-04-25. 
  36. ↑ Lua error in Module:Citation/CS1/Identifiers at line 630: attempt to index field 'known_free_doi_registrants_t' (a nil value).
  37. ↑ Geller C, Varbanov M, Duval RE (November 2012). "Human coronaviruses: insights into environmental resistance and its influence on the development of new antiseptic strategies". Viruses. 4 (11): 3044–68. doi:10.3390/v4113044. PMC 3509683. PMID 23202515.
  38. ↑ Lua error in Module:Citation/CS1/Identifiers at line 630: attempt to index field 'known_free_doi_registrants_t' (a nil value).
  39. ↑ Lua error in Module:Citation/CS1/Identifiers at line 630: attempt to index field 'known_free_doi_registrants_t' (a nil value).

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