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B.1.351
The Beta variant, (B.1.351), was a variant of SARS-CoV-2, the virus that causes COVID-19. One of several SARS-CoV-2 variants initially believed to be of particular importance, it was first detected in the Nelson Mandela Bay metropolitan area of the Eastern Cape province of South Africa in October 2020, which was reported by the country's health department on 18 December 2020. Phylogeographic analysis suggests this variant emerged in the Nelson Mandela Bay area in July or August 2020. The World Health Organization labelled the variant as Beta variant, not to replace the scientific name but as a name for the public to commonly refer to. The WHO considers it to be a variant of concern no longer in circulation. Names The variant is also known as the ''South African variant''. Mutations File:SARS-CoV-2 Beta variant.svg, Amino acid mutations of SARS-CoV-2 Beta variant plotted on a genome map of SARS-CoV-2 with a focus on Spike. There are three mutations of particular i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Variants Of SARS-CoV-2
There are many variants of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the virus that causes coronavirus disease 2019 (COVID-19). Some are believed, or have been stated, to be of particular importance due to their potential for increased transmissibility, increased virulence, or reduced effectiveness of vaccines against them. These variants contribute to the continuation of the COVID-19 pandemic. only the Omicron variant is designated as a circulating variant of concern by the World Health Organization. Overview The emergence of SARS-CoV-2 may have resulted from recombination events between a bat SARS-like coronavirus and a pangolin coronavirus through cross-species transmission. The earliest available SARS-CoV-2 viral genomes were collected from patients in December 2019, and Chinese researchers compared these early genomes with bat and pangolin coronavirus strains to estimate the ancestral human coronavirus type; the identified ancestral genome ty ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Severe Acute Respiratory Syndrome Coronavirus 2
Severe acute respiratory syndrome coronavirus 2 (SARS‑CoV‑2) is a strain of coronavirus that causes COVID-19 (coronavirus disease 2019), the respiratory illness responsible for the ongoing COVID-19 pandemic. The virus previously had a provisional name, 2019 novel coronavirus (2019-nCoV), and has also been called the human coronavirus 2019 (HCoV-19 or hCoV-19). First identified in the city of Wuhan, Hubei, China, the World Health Organization declared the outbreak a public health emergency of international concern on January 30, 2020, and a pandemic on March 11, 2020. SARS‑CoV‑2 is a positive-sense single-stranded RNA virus that is contagious in humans. SARS‑CoV‑2 is a virus of the species '' severe acute respiratory syndrome–related coronavirus'' (SARSr-CoV), related to the SARS-CoV-1 virus that caused the 2002–2004 SARS outbreak. Despite its close relation to SARS-CoV-1, its closest known relatives, with which it forms a sister group, are the derived ... [...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 (coronavirus disease 2019), the respiratory illness responsible for the ongoing COVID-19 pandemic. The virus previously had a Novel coronavirus, provisional name, 2019 novel coronavirus (2019-nCoV), and has also been called the human coronavirus 2019 (HCoV-19 or hCoV-19). First identified in the city of Wuhan, Hubei, China, the World Health Organization declared the outbreak a public health emergency of international concern on January 30, 2020, and a pandemic on March 11, 2020. SARS‑CoV‑2 is a positive-sense single-stranded RNA virus that is Contagious disease, contagious in humans. SARS‑CoV‑2 is a virus of the species ''severe acute respiratory syndrome–related coronavirus'' (SARSr-CoV), related to the Severe acute respiratory syndrome coronavirus 1, SARS-CoV-1 virus that caused the 2002–2004 SARS outbreak. Despite its close relation to SARS-CoV-1, i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
COVID-19
Coronavirus disease 2019 (COVID-19) is a contagious disease caused by a virus, the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The first known case was identified in Wuhan, China, in December 2019. The disease quickly spread worldwide, resulting in the COVID-19 pandemic. The symptoms of COVID‑19 are variable but often include fever, cough, headache, fatigue, breathing difficulties, loss of smell, and loss of taste. Symptoms may begin one to fourteen days after exposure to the virus. At least a third of people who are infected 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, or more than 50% lung involvement on imaging), and 5% develop critical symptoms ( respiratory failure, shock, or multiorgan dysfunction). Older people are at a higher risk of developing ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
South African COVID Variant
South African variant can refer to several variants of SARS-CoV-2: * SARS-CoV-2 Beta variant (B.1.351), first detected in the Eastern Cape province of South Africa in October 2020 * SARS-CoV-2 lineage C.1.2, first identified in May 2021 in South Africa * SARS-CoV-2 Omicron variant (B.1.1.529), first reported to the WHO from South Africa in November 2021, though later found in older samples from Botswana See also * Variants of SARS-CoV-2 {{disambig ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ORF3a
ORF3a (previously known as X1 or U274) is a gene found in coronaviruses of the subgenus ''Sarbecovirus'', including SARS-CoV and SARS-CoV-2. It encodes an accessory protein about 275 amino acid residues long, which is thought to function as a viroporin. It is the largest accessory protein and was the first of the SARS-CoV accessory proteins to be described. Comparative genomics ORF3a is well conserved within the subgenus ''Sarbecovirus''. The protein has 73% sequence identity between SARS-CoV (274 residues) and SARS-CoV-2 (275 residues). Within the ORF3a open reading frame there are several overlapping genes in the genome: ORF3a, ORF3b, and (in SARS-CoV-2 only) ORF3c. In SARS-CoV-2, the overlap between ORF3a, ORF3c, and ORF3d potentially represents a rare example of all three possible reading frames of the same sequence region encoding functional proteins. Although ORF3a is present in ''Sarbecovirus'', it is absent in another ''Betacoronavirus'' subgenus, ''Embecovirus'', wh ... [...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 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 helical transmembrane domain, and a somewhat hydrophilic C-terminal region. In SARS-CoV and SARS-CoV-2, the C-terminal region contains a PDZ domain binding motif (PBM). This feature appears to be conserved only in the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coronavirus Nucleocapsid Protein
The nucleocapsid (N) protein is a protein that packages the positive-sense RNA genome of coronaviruses to form ribonucleoprotein structures enclosed within the viral capsid. The N protein is the most highly expressed of the four major coronavirus structural proteins. In addition to its interactions with RNA, N forms protein-protein interactions with the coronavirus membrane protein (M) during the process of viral assembly. N also has additional functions in manipulating the cell cycle of the host cell. The N protein is highly immunogenic and antibodies to N are found in patients recovered from SARS and Covid-19. History The coronavirus from Wuhan, China was first identified in January 2020. A patient in the state of Washington was given a diagnosis of coronavirus infection on 20 January. A group of scientists based at the Centers for Disease Control and Prevention in Atlanta, Georgia isolated the virus from nasopharyngeal and oropharyngeal swabs and were able to charac ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Scribd
Scribd Inc. is an American e-book and audiobook subscription service that includes one million titles. Scribd hosts 60 million documents on its open publishing platform. The company was founded in 2007 by Trip Adler, Jared Friedman, and Tikhon Bernstam, and headquartered in San Francisco, California. Scribd's e-book subscription service is available on Android and iOS smartphones and tablets, as well as the Kindle Fire, Nook, and personal computers. Subscribers can access unlimited books a month from 1,000 publishers, including Bloomsbury, Harlequin, HarperCollins, Houghton Mifflin Harcourt, Lonely Planet, Macmillan, Perseus Book Group, Simon & Schuster, Wiley, and Workman. Scribd has 80 million users, and has been referred to as "the Netflix for books". History Founding (2007–2013) Scribd began as a site to host and share documents. While at Harvard, Trip Adler was inspired to start Scribd after learning about the lengthy process required to publish academic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Betacoronavirus
''Betacoronavirus'' (β-CoVs or Beta-CoVs) is one of four genera ('' Alpha''-, ''Beta-'', '' Gamma-'', and '' Delta-'') of coronaviruses. Member viruses are enveloped, positive-strand RNA viruses that infect mammals (of which humans are part). 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. 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 OC43 and HKU1 (which can cause the common cold) of lineage A, SARS-CoV and SARS-CoV-2 (which has caused the disease COVID-19) of lineage B, and MER ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
CAPRISA
CAPRISA ("Centre for the AIDS Programme of Research in South Africa") is the name of an AIDS research center based in Durban, South Africa. History CAPRISA was established in 2002 under the National Institutes of Health program called Comprehensive International Program of Research on AIDS (CIPRA). Five partner institutions participated in the founding: University of KwaZulu-Natal, University of Cape Town, University of Western Cape, National Institute of Communicable Diseases, and Columbia University in New York. UNAIDS recognizes CAPRISA with the designation of "Collaborating Centre for HIV Prevention Research." CAPRISA's mission is to promote HIV prevention and research its epidemiology. CAPRISA 004 CAPRISA 004 is the name of a clinical trial testing a microbicide An antimicrobial is an agent that kills microorganisms or stops their growth. Antimicrobial medicines can be grouped according to the microorganisms they act primarily against. For example, antibiotics a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ORF1ab
ORF1ab (also ORF1a/b) refers collectively to two open reading frames (ORFs), ORF1a and ORF1b, that are conserved in the genomes of nidoviruses, a group of viruses that includes coronaviruses. The genes express large polyproteins that undergo proteolysis to form several nonstructural proteins with various functions in the viral life cycle, including proteases and the components of the replicase-transcriptase complex (RTC). Together the two ORFs are sometimes referred to as the replicase gene. They are related by a programmed ribosomal frameshift that allows the ribosome to continue translating past the stop codon at the end of ORF1a, in a -1 reading frame. The resulting polyproteins are known as pp1a and pp1ab. Expression ORF1a is the first open reading frame at the 5' end of the genome. Together ORF1ab occupies about two thirds of the genome, with the remaining third at the 3' end encoding the structural proteins and accessory proteins. It is translated from a 5' capped ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
