Alphacoronavirus

Last updated
Alphacoronavirus
12985 2015 421 Fig1 HTML.webp
Porcine epidemic diarrhea virus genome and virion structure
Virus classification OOjs UI icon edit-ltr.svg
(unranked): Virus
Realm: Riboviria
Kingdom: Orthornavirae
Phylum: Pisuviricota
Class: Pisoniviricetes
Order: Nidovirales
Family: Coronaviridae
Subfamily: Orthocoronavirinae
Genus:Alphacoronavirus
Subgenera and species

See text

Alphacoronaviruses (Alpha-CoV) are members of the first of the four genera (Alpha-, Beta- , Gamma- , and Delta- ) of coronaviruses. They are positive-sense, single-stranded RNA viruses that infect mammals, including humans. They have spherical virions with club-shaped surface projections formed by trimers of the spike protein, and a viral envelope.

Contents

Alphacoronaviruses are in the subfamily Orthocoronavirinae of the family Coronaviridae . Both the Alpha- and Betacoronavirus lineages descend from the bat viral gene pool. [1] [2] Alphacoronaviruses were previously known as "phylogroup 1 coronaviruses".

The Alphacoronavirus genus is very diverse, particularly in bats. Most bat originating strains haven't been successfully isolated and cultured in laboratory. Alphacoronaviruses infecting other mammal species have been much better studied, see List of Coronavirus live isolates.

Etymology

The name alphacoronavirus is derived from Ancient Greek ἄλφα (álpha, "the first letter of the Greek alphabet"), and κορώνη (korṓnē, "garland, wreath"), meaning crown, which describes the appearance of the surface projections seen under electron microscopy that resemble a solar corona. [3]

Structure

The virion is enveloped and spherical measuring 120–160 nm in diameter and a core shell of about 65 nm. Glycoproteins and trimers form large surface projections which create the appearance of solar corona. This genus, like other coronaviruses, has a spike protein with a type I fusion machine (S2) and a receptor-binding domain (S1). It assembles into a trimer. Unlike beta- and gammacoronaviruses, this protein is not cleaved into two halves. [4]

Genome

Genetic relationships between the different feline coronaviruses (FCov) and canine coronaviruses (CCoV) genotypes. Recombination at arrows. 609465.fig.001.jpg
Genetic relationships between the different feline coronaviruses (FCov) and canine coronaviruses (CCoV) genotypes. Recombination at arrows.

The genome is positive-sense, single-stranded RNA with a length of 27 to 29 kilobases and a 3'-polyA tail. Two large, overlapping ORFs at the 5'-end of the genome encode the major non-structural proteins expressed as a fusion protein by ribosomal frameshift. These include regions with protease, helicase and RNA polymerase motifs. There are seven other genes downstream which encode structural proteins. These are expressed from a 3'-coterminal nested set of subgenomic mRNAs.

Recombination

Both types of Alphacoronavirus 1 , feline coronavirus (FCoV) and canine coronavirus (CCoV), are known to exist in two serotypes. Serotype II targets Aminopeptidase N, while the receptor for Serotype I is unknown. The difference is due to a different spike protein. [6] There is a common ancestor for FCoV and CCoV. This ancestor gradually evolved into FCoV I and CCoV I. An S protein from an unknown virus was recombined into the ancestor and gave rise to CCoV II. CCoV II once again recombined with FCoV to create FCoV II. CCoV II gradually evolved into TGEV. A spike deletion in TGEV creates PRCV. All these viruses are sorted into the subgenus Tegacovirus . [6]

Classification

Phylogentic tree of the genus Alphacoronaviruses with host animals indicated on the right hand side. Viruses-11-00423-g004.png
Phylogentic tree of the genus Alphacoronaviruses with host animals indicated on the right hand side.

The following subgenera and species are recognized: [7]

See also

Related Research Articles

<span class="mw-page-title-main">Coronavirus</span> Subfamily of viruses in the family Coronaviridae

Coronaviruses are a group of related RNA viruses that cause diseases in mammals and birds. In humans and birds, they cause respiratory tract infections that can range from mild to lethal. Mild illnesses in humans include some cases of the common cold, while more lethal varieties can cause SARS, MERS and COVID-19, which is causing the ongoing pandemic. In cows and pigs they cause diarrhea, while in mice they cause hepatitis and encephalomyelitis.

<i>Coronaviridae</i> Family of viruses in the order Nidovirales

Coronaviridae is a family of enveloped, positive-strand RNA viruses which infect amphibians, birds, and mammals. The group includes the subfamilies Letovirinae and Orthocoronavirinae; the members of the latter are known as coronaviruses.

<span class="mw-page-title-main">Canine coronavirus</span> Species of virus

Canine coronavirus (CCoV) is an enveloped, positive-sense, single-stranded RNA virus which is a member of the species Alphacoronavirus 1. It causes a highly contagious intestinal disease worldwide in dogs. The infecting virus enters its host cell by binding to the APN receptor. It was discovered in 1971 in Germany during an outbreak in sentry dogs. The virus is a member of the genus Alphacoronavirus and subgenus Tegacovirus.

Feline coronavirus (FCoV) is a positive-stranded RNA virus that infects cats worldwide. It is a coronavirus of the species Alphacoronavirus 1, which includes canine coronavirus (CCoV) and porcine transmissible gastroenteritis coronavirus (TGEV). FCoV has two different forms: feline enteric coronavirus (FECV), which infects the intestines, and feline infectious peritonitis virus (FIPV), which causes the disease feline infectious peritonitis (FIP).

<span class="mw-page-title-main">Transmissible gastroenteritis virus</span> Species of virus

Transmissible gastroenteritis virus or Transmissible gastroenteritis coronavirus (TGEV) is a coronavirus which infects pigs. It is an enveloped, positive-sense, single-stranded RNA virus which enters its host cell by binding to the APN receptor. The virus is a member of the genus Alphacoronavirus, subgenus Tegacovirus, species Alphacoronavirus 1.

Bovine coronavirus is a coronavirus which is a member of the species Betacoronavirus 1. The infecting virus is an enveloped, positive-sense, single-stranded RNA virus which enters its host cell by binding to the N-acetyl-9-O-acetylneuraminic acid recepter. Infection causes calf enteritis and contributes to the enzootic pneumonia complex in calves. It can also cause winter dysentery in adult cattle. It can infect both domestic and wild ruminants and has a worldwide distribution. Transmission is horizontal, via oro-fecal or respiratory routes. Like other coronaviruses from genus Betacoronavirus, subgenus Embecovirus, it has a surface protein called hemagglutinin esterase (HE) in addition to the four structural proteins shared by all coronaviruses.

<i>Human coronavirus HKU1</i> Species of virus

Human coronavirus HKU1 (HCoV-HKU1) is a species of coronavirus in humans and animals. It causes an upper respiratory disease with symptoms of the common cold, but can advance to pneumonia and bronchiolitis. It was first discovered in January 2004 from one man in Hong Kong. Subsequent research revealed it has global distribution and earlier genesis.

<i>Betacoronavirus</i> Genus of viruses

Betacoronavirus is one of four genera of coronaviruses. Member viruses are enveloped, positive-strand RNA viruses that infect mammals. The natural reservoir for betacoronaviruses are bats and rodents. Rodents are the reservoir for the subgenus Embecovirus, while bats are the reservoir for the other subgenera.

<span class="mw-page-title-main">Human coronavirus OC43</span> Species of virus

Human coronavirus OC43 (HCoV-OC43) is a member of the species Betacoronavirus 1, which infects humans and cattle. The infecting coronavirus is an enveloped, positive-sense, single-stranded RNA virus that enters its host cell by binding to the N-acetyl-9-O-acetylneuraminic acid receptor. OC43 is one of seven coronaviruses known to infect humans. It is one of the viruses responsible for the common cold and may have been responsible for the 1889–1890 pandemic. It has, like other coronaviruses from genus Betacoronavirus, subgenus Embecovirus, an additional shorter spike protein called hemagglutinin-esterase (HE).

<i>Human coronavirus 229E</i> Species of virus

Human coronavirus 229E (HCoV-229E) is a species of coronavirus which infects humans and bats. It is an enveloped, positive-sense, single-stranded RNA virus which enters its host cell by binding to the APN receptor. Along with Human coronavirus OC43, it is one of the viruses responsible for the common cold. HCoV-229E is a member of the genus Alphacoronavirus and subgenus Duvinacovirus.

Tylonycteris bat coronavirus HKU4 is an enveloped, positive-sense single-stranded RNA virus mammalian Group 2 Betacoronavirus that has been found to be genetically related to the Middle East respiratory syndrome-related coronavirus (MERS-CoV) that is responsible for the 2012 Middle East respiratory syndrome coronavirus outbreak in Saudi Arabia, Jordan, United Arab Emirates, the United Kingdom, France, and Italy.

Rhinolophus bat coronavirus HKU2 is a novel enveloped, single-stranded positive-sense RNA virus species in the Alphacoronavirus, or Group 1, genus with a corona-like morphology.

Scotophilus bat coronavirus 512 is an enveloped, single-stranded positive-sense RNA virus species in the Alphacoronavirus, or Group 1, genus with a corona-like morphology. It was isolated from a lesser Asiatic yellow house bat discovered in southern China.

<i>Coronavirus HKU15</i> Species of virus

Coronavirus HKU15, sometimes called Porcine coronavirus HKU15 is a virus first discovered in a surveillance study in Hong Kong, China, and first reported to be associated with porcine diarrhea in February 2014. In February 2014, PorCoV HKU15 was identified in pigs with clinical diarrhea disease in the U.S. state of Ohio. The complete genome of one US strain has been published. Since then, it has been identified in pig farms in Canada. The virus has been referred to as Porcine coronavirus HKU15, Swine deltacoronavirus and Porcine deltacoronavirus.

<i>Embecovirus</i> Subgenus of viruses

Embecovirus is a subgenus of coronaviruses in the genus Betacoronavirus. The viruses in this subgenus, unlike other coronaviruses, have a hemagglutinin esterase (HE) gene. The viruses in the subgenus were previously known as group 2a coronaviruses.

<i>Merbecovirus</i> Subgenus of viruses

Merbecovirus is a subgenus of viruses in the genus Betacoronavirus, including the human pathogen Middle East respiratory syndrome–related coronavirus (MERS-CoV). The viruses in this subgenus were previously known as group 2c coronaviruses.

Nobecovirus is a subgenus of viruses in the genus Betacoronavirus. The viruses in the group were previously known as group 2d coronaviruses.

<span class="mw-page-title-main">Coronavirus diseases</span> List of Coronavirus diseases

Coronavirus diseases are caused by viruses in the coronavirus subfamily, a group of related RNA viruses that cause diseases in mammals and birds. In humans and birds, the group of viruses cause respiratory tract infections that can range from mild to lethal. Mild illnesses in humans include some cases of the common cold, while more lethal varieties can cause SARS, MERS and COVID-19. As of 2021, 45 species are registered as coronaviruses, whilst 11 diseases have been identified, as listed below.

<span class="mw-page-title-main">History of coronavirus</span> History of the virus group

The history of coronaviruses is an account of the discovery of the diseases caused by coronaviruses and the diseases they cause. It starts with the first report of a new type of upper-respiratory tract disease among chickens in North Dakota, U.S., in 1931. The causative agent was identified as a virus in 1933. By 1936, the disease and the virus were recognised as unique from other viral disease. They became known as infectious bronchitis virus (IBV), but later officially renamed as Avian coronavirus.

<i>Alphacoronavirus 1</i> Species of virus

Alphacoronavirus 1 is a species of coronavirus that infects cats, dogs and pigs. It includes the virus strains feline coronavirus, canine coronavirus, and transmissible gastroenteritis virus. It is an enveloped, positive-strand RNA virus which is able to enter its host cell by binding to the APN receptor.

References

  1. Woo, P. C.; Wang, M.; Lau, S. K.; Xu, H.; Poon, R. W.; Guo, R.; Wong, B. H.; Gao, K.; Tsoi, H. W.; Huang, Y.; Li, K. S.; Lam, C. S.; Chan, K. H.; Zheng, B. J.; Yuen, K. Y. (2007). "Comparative analysis of twelve genomes of three novel group 2c and group 2d coronaviruses reveals unique group and subgroup features". Journal of Virology. 81 (4): 1574–85. doi:10.1128/JVI.02182-06. PMC   1797546 . PMID   17121802.
  2. Lau, S. K.; Woo, P. C.; Yip, C. C.; Fan, R. Y.; Huang, Y.; Wang, M.; Guo, R.; Lam, C. S.; Tsang, A. K.; Lai, K. K.; Chan, K. H.; Che, X. Y.; Zheng, B. J.; Yuen, K. Y. (2012). "Isolation and characterization of a novel Betacoronavirus subgroup A coronavirus, rabbit coronavirus HKU14, from domestic rabbits". Journal of Virology. 86 (10): 5481–96. doi:10.1128/JVI.06927-11. PMC   3347282 . PMID   22398294.
  3. Decaro, Nicola (2011). "Alphacoronavirus". The Springer Index of Viruses. pp. 371–383. doi:10.1007/978-0-387-95919-1_56. ISBN   978-0-387-95918-4. S2CID   216061230.
  4. Wrapp, Daniel; McLellan, Jason S.; Gallagher, Tom (13 November 2019). "The 3.1-Angstrom Cryo-electron Microscopy Structure of the Porcine Epidemic Diarrhea Virus Spike Protein in the Prefusion Conformation". Journal of Virology. 93 (23): e00923-19. doi:10.1128/JVI.00923-19. PMC   6854500 . PMID   31534041.
  5. Le Poder, Sophie (2011-07-31). "Feline and Canine Coronaviruses: Common Genetic and Pathobiological Features". Advances in Virology. 2011: 609465. doi: 10.1155/2011/609465 . PMC   3265309 . PMID   22312347.
  6. 1 2 Jaimes, Javier A.; Millet, Jean K.; Stout, Alison E.; André, Nicole M.; Whittaker, Gary R. (10 January 2020). "A Tale of Two Viruses: The Distinct Spike Glycoproteins of Feline Coronaviruses". Viruses. 12 (1): 83. doi: 10.3390/v12010083 . PMC   7019228 . PMID   31936749.
  7. "Virus Taxonomy: 2019 Release". talk.ictvonline.org. International Committee on Taxonomy of Viruses. Retrieved 20 June 2020.