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Coronavirus
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 (which is also caused by other viruses, predominantly rhinoviruses), while more lethal varieties can cause SARS, MERS and COVID-19. In cows and pigs they cause diarrhea, while in mice they cause hepatitis and encephalomyelitis. Coronaviruses constitute the subfamily ''Orthocoronavirinae'', in the family ''Coronaviridae'', order ''Nidovirales'' and realm ''Riboviria''. They are enveloped viruses with a Positive-strand RNA virus, positive-sense single-stranded RNA genome and a nucleocapsid of helical symmetry. The genome size of coronaviruses ranges from approximately 26 to 32 kilobases, one of the largest among RNA viruses. They have characteristic club-shaped Spike protein, spikes that project from their surface, which in electron ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
COVID-19
Coronavirus disease 2019 (COVID-19) is a contagious disease caused by the coronavirus SARS-CoV-2. In January 2020, the disease spread worldwide, resulting in the COVID-19 pandemic. The symptoms of COVID‑19 can vary but often include fever, fatigue, cough, breathing difficulties, anosmia, loss of smell, and ageusia, loss of taste. Symptoms may begin one to fourteen days incubation period, after exposure to the virus. At least a third of people who are infected asymptomatic, do not develop noticeable symptoms. Of those who develop symptoms noticeable enough to be classified as patients, most (81%) develop mild to moderate symptoms (up to mild pneumonia), while 14% develop severe symptoms (dyspnea, hypoxia (medical), hypoxia, or more than 50% lung involvement on imaging), and 5% develop critical symptoms (respiratory failure, shock (circulatory), shock, or organ dysfunction, multiorgan dysfunction). Older people have a higher risk of developing severe symptoms. Some complicati ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
SARS-CoV-2
Severe acute respiratory syndrome coronavirus 2 (SARS‑CoV‑2) is a strain of coronavirus that causes COVID-19, the respiratory illness responsible for the COVID-19 pandemic. The virus previously had the Novel coronavirus, provisional name 2019 novel coronavirus (2019-nCoV), and has also been called human coronavirus 2019 (HCoV-19 or hCoV-19). First identified in the city of Wuhan, Hubei, China, the World Health Organization designated the outbreak a public health emergency of international concern from January 30, 2020, to May 5, 2023. SARS‑CoV‑2 is a positive-sense single-stranded RNA virus that is Contagious disease, contagious in humans. SARS‑CoV‑2 is a strain of the species ''Betacoronavirus pandemicum'' (SARSr-CoV), as is SARS-CoV-1, the virus that caused the 2002–2004 SARS outbreak. There are animal-borne coronavirus strains more closely related to SARS-CoV-2, the most closely known relative being the BANAL-52 bat coronavirus. SARS-CoV-2 is of Zoonosis, z ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coronavirus Spike Protein
Spike (S) glycoprotein (sometimes also called spike protein, formerly known as E2) is the largest of the four major structural proteins found in coronaviruses. The spike protein assembles into trimers that form large structures, called spikes or peplomers, that project from the surface of the virion. The distinctive appearance of these spikes when visualized using negative stain transmission electron microscopy, "recalling the solar corona", gives the virus family its main name. The function of the spike glycoprotein is to mediate viral entry into the host cell by first interacting with molecules on the exterior cell surface and then fusing the viral and cellular membranes. Spike glycoprotein is a class I fusion protein that contains two regions, known as S1 and S2, responsible for these two functions. The S1 region contains the receptor-binding domain that binds to receptors on the cell surface. Coronaviruses use a very diverse range of receptors; HCoV-NL63, SARS-CoV ( ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
MERS
Middle East respiratory syndrome (MERS) is a viral respiratory infection caused by '' Middle East respiratory syndrome–related coronavirus'' (MERS-CoV). Symptoms may range from none, to mild, to severe depending on age and risk level. Typical symptoms include fever, cough, diarrhea, and shortness of breath. The disease is typically more severe in those with other health problems. The first case was identified in June 2012 by Egyptian physician Ali Mohamed Zaki at the Dr. Soliman Fakeeh Hospital in Jeddah, Saudi Arabia, and most cases have occurred in the Arabian Peninsula. Over 2,600 cases have been reported as of January 2021, including 45 cases in the year 2020. About 35% of those who are diagnosed with the disease die from it. Larger outbreaks have occurred in South Korea in 2015 and in Saudi Arabia in 2018. MERS-CoV is a virus in the coronavirus family believed to be originally from bats. However, humans are typically infected from camels, either during direct ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coronaviridae
''Coronaviridae'' is a family (biology), family of Viral envelope, enveloped, positive-strand RNA viruses which infect fish, amphibians, birds, and mammals. The group includes the subfamilies ''Letovirinae,'' ''Orthocoronavirinae'', and ''Pitovirinae''. The members of the subfamily ''Orthocoronavirinae'' are known as Coronavirus, coronaviruses. The viral genome is 26–32 kilobases in length. The particles are typically decorated with large (~20 nm), club- or petal-shaped surface projections (the "peplomers" or "spikes"), which in electron micrographs of spherical particles create an image reminiscent of the solar corona. Virology The 5' and 3' ends of the genome have a Five-prime cap, cap and poly(A) tract, respectively. The viral envelope, obtained by budding through membranes of the endoplasmic reticulum (ER) or Golgi apparatus, invariably contains two virus-specified glycoprotein species, known as the spike (S) and membrane (M) proteins. The coronavirus spike protein, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coronavirus Membrane Protein
The membrane (M) protein (previously called E1, sometimes also matrix protein) is an integral membrane protein that is the most abundant of the four major structural proteins found in coronaviruses. The M protein organizes the assembly of coronavirus virions through protein-protein interactions with other M protein molecules as well as with the other three structural proteins, the envelope (E), spike (S), and nucleocapsid (N) proteins. Structure The M protein is a transmembrane protein with three transmembrane domains and is around 230 amino acid residues long. In SARS-CoV-2, the causative agent of COVID-19, the M protein is 222 residues long. Its membrane topology orients the C-terminus toward the cytosolic face of the membrane and thus into the interior of the virion. It has a short N-terminal segment and a larger C-terminal domain. Although the protein sequence is not well conserved across all coronavirus groups, there is a conserved amphipathic region near the C-termi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Betacoronavirus
''Betacoronavirus'' (β-CoVs or Beta-CoVs) is one of four genera (''Alphacoronavirus, Alpha''-, ''Beta-'', ''Gammacoronavirus, Gamma-'', and ''Deltacoronavirus (genus), Delta-'') of coronaviruses. Member viruses are Viral envelope, enveloped, positive-strand RNA viruses that infect mammals, including humans. The natural reservoir for betacoronaviruses are bats and rodents. Rodents are the reservoir for the subgenus ''Embecovirus'', while Bat virome, bats are the reservoir for the other subgenera. The coronavirus genera are each composed of varying viral lineages with the betacoronavirus genus containing four such lineages: A, B, C, D. In older literature, this genus is also known as "group 2 coronaviruses". The genus is in the subfamily ''Orthocoronavirinae'' in the family ''Coronaviridae'', of the order ''Nidovirales''. The betacoronaviruses of the greatest clinical importance concerning humans are Human coronavirus OC43, OC43 and Human coronavirus HKU1, HKU1 (which can cause ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coronavirus Envelope Protein
The envelope (E) protein is the smallest and least well-characterized of the four major structural proteins found in coronavirus virions. It is an integral membrane protein less than 110 amino acid residues long; in SARS-CoV-2, the causative agent of Covid-19, the E protein is 75 residues long. Although it is not necessarily essential gene, essential for viral replication, absence of the E protein may produce abnormally assembled viral capsids or reduced replication. E is a multifunctional protein and, in addition to its role as a structural protein in the viral capsid, it is thought to be involved in viral assembly, likely functions as a viroporin, and is involved in viral pathogenesis. Structure The E protein consists of a short hydrophilic N-terminal region, a hydrophobic transmembrane helix, helical transmembrane domain, and a somewhat hydrophilic C-terminal region. In SARS-CoV and SARS-CoV-2, the C-terminal region contains a PDZ-binding motif (PBM). This feature appears to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
SARS
Severe acute respiratory syndrome (SARS) is a viral respiratory disease of zoonotic origin caused by the virus SARS-CoV-1, the first identified strain of the SARS-related coronavirus. The first known cases occurred in November 2002, and the syndrome caused the 2002–2004 SARS outbreak. In 2004, Xue Wu Zhang and Yee Leng Yap found that the Spike 2 (S2) protein of SARS is structurally similar to HIV-1 gp41 subunit, suggesting an analogous membrane fusion mechanism between the two. In the 2010s, Chinese scientists traced the virus through the intermediary of Asian palm civets to cave-dwelling horseshoe bats in Xiyang Yi Ethnic Township, Yunnan.The locality was referred to be "a cave in Kunming" in earlier sources because the Xiyang Yi Ethnic Township is administratively part of Kunming, though 70 km apart. Xiyang was identified on * For an earlier interview of the researchers about the locality of the caves, see: SARS was a relatively rare disease; at the end of the ep ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alphacoronavirus
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. Alphacoronaviruses are in the subfamily ''Orthocoronavirinae'' of the family '' Coronaviridae''. Both the ''Alpha''- and ''Betacoronavirus'' lineages descend from the bat viral gene pool. 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 ( ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Positive-strand RNA Virus
Positive-strand RNA viruses (+ssRNA viruses) are a group of related viruses that have Sense (molecular biology), positive-sense, single-stranded genomes made of ribonucleic acid. The positive-sense genome can act as messenger RNA (mRNA) and can be directly translation (biology), translated into viral proteins by the host cell, host cell's ribosomes. Positive-strand RNA viruses encode an RNA-dependent RNA polymerase (RdRp) which is used during replication of the genome to synthesize a negative-sense antigenome that is then used as a template to create a new positive-sense viral genome. Positive-strand RNA viruses are divided between the phyla ''Kitrinoviricota'', ''Lenarviricota'', and ''Pisuviricota'' (specifically classes ''Pisoniviricetes'' and ''Stelpaviricetes, Stelpavirictes'') all of which are in the kingdom ''Orthornavirae'' and Realm (virology), realm ''Riboviria''. They are Monophyly, monophyletic and descended from a common RNA virus ancestor. In the Baltimore classi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gammacoronavirus
''Gammacoronavirus'' (Gamma-CoV) is one of the four genera (''Alphacoronavirus, Alpha''-, ''Betacoronavirus, Beta-'', ''Gamma-'', and ''Deltacoronavirus (genus), Delta-'') of coronaviruses. It is in the subfamily ''Orthocoronavirinae'' of the family ''Coronaviridae''. They are Viral envelope, enveloped, Sense (molecular biology), positive-sense, Base pair, single-stranded RNA viruses of Zoonosis, zoonotic origin. Coronaviruses infect both animals and humans. While the alpha and beta genera are derived from the bat gene pool, the gamma and delta genera are derived from the avian and pig gene pools. Gamma-CoV also known as coronavirus group 3 are the avian coronaviruses. Taxonomy The genus contains the following subgenera and species: * Subgenus: ''Brangacovirus'' ** ''Gammacoronavirus brantae'', Goose coronavirus CB17 * Subgenus: ''Cegacovirus'' ** ''Gammacoronavirus delphinapteri'', Beluga whale coronavirus SW1 * Subgenus: ''Igacovirus'' ** ''Gammacoronavirus anatis'', Duck co ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
