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B.1.1.7
The Alpha variant (B.1.1.7) was a SARS-CoV-2 variant of concern. It was estimated to be 40–80% more transmissible than the wild-type SARS-CoV-2 (with most estimates occupying the middle to higher end of this range). It was first detected in November 2020 from a sample taken in September in the United Kingdom, and began to spread quickly by mid-December, around the same time as infections surged. This increase is thought to be at least partly because of one or more mutations in the virus' spike protein. The variant was also notable for having more mutations than normally seen. By January 2021, more than half of all genomic sequencing of SARS-CoV-2 was carried out in the UK. This had given rise to questions as to how many other important variants were circulating around the world undetected. On 2 February 2021, Public Health England reported that they had detected " limited number of B.1.1.7 VOC-202012/01 genomes with E484K mutations", which they dubbed Variant of Concern ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
E484K Mutation
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 t ... [...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 type ... [...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 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 SARS ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
COVID-19 Genomics UK (COG-UK) Consortium
The COVID-19 Genomics UK Consortium (COG-UK) is a group of public health agencies and academic institutions in the United Kingdom created in April 2020 to collect, sequence and analyse genomes of SARS-CoV-2 as part of COVID-19 pandemic response. The consortium comprises the UK's four public health agencies, National Health Service organisations, academic partners and the Wellcome Sanger Institute. The consortium is known for first identifying the SARS-CoV-2 Alpha variant (at the time, referred to as Variant of Concern 202012/01) in November 2020. As of January 2021, 45% of all SARS-CoV-2 sequences uploaded to the GISAID sequencing database originated from COG-UK. In April 2021, COG-UK began the planned transition of sequencing to a national service, with completion by September 2021. COG-UK have stated that their priorities following this transition are data linkage, research and international training. Impact The early and large-scale coordinated national sequencing of SARS-C ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
SARS-CoV-2 Beta Variant
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 interes ... [...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 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; SARS-CoV (which causes SARS) an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
SARS-CoV-2 Gamma Variant
The Gamma variant (P.1) was one of the variants of SARS-CoV-2, the virus that causes COVID-19. This variant of SARS-CoV-2 has been named lineage P.1 and has 17 amino acid substitutions, ten of which in its spike protein, including these three designated to be of particular concern: N501Y, E484K and K417T. This variant of SARS-CoV-2 was first detected by the National Institute of Infectious Diseases (NIID) of Japan, on 6 January 2021 in four people who had arrived in Tokyo having visited Amazonas, Brazil, four days earlier. It was subsequently declared to be in circulation in Brazil. Under the simplified naming scheme proposed by the World Health Organization, P.1 has been labeled Gamma variant, and is currently considered a variant of concern. Gamma caused widespread infection in early 2021 in the city of Manaus, the capital of Amazonas, although the city had already experienced widespread infection in May 2020, with a study indicating high seroprevalence of antibodies for ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Variant Of Concern
The term variant of concern (VOC) for SARS-CoV-2, which causes COVID-19, is a category used for variants of the virus where mutations in their spike protein receptor binding domain (RBD) substantially increase binding affinity (e.g., N501Y) in RBD-hACE2 complex (genetic data), while also being linked to rapid spread in human populations (epidemiological data). Before this, an emerging variant may have been labeled a variant of interest, or in some countries a variant under investigation. During or after fuller assessment as a variant of concern the variant is typically assigned to a lineage in the PANGOLIN nomenclature system and to clades in the Nextstrain and GISAID systems. During the COVID-19 pandemic, the SARS-CoV-2 virus has been observed to mutate, with certain combinations of specific point mutations proving to be more concerning than others. This was principally for reasons of transmissibility and virulence, and also with regard to the possible emergence of escape ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gene
In biology, the word gene (from , ; "...Wilhelm Johannsen coined the word gene to describe the Mendelian units of heredity..." meaning ''generation'' or ''birth'' or ''gender'') can have several different meanings. The Mendelian gene is a basic unit of heredity and the molecular gene is a sequence of nucleotides in DNA that is transcribed to produce a functional RNA. There are two types of molecular genes: protein-coding genes and noncoding genes. During gene expression, the DNA is first copied into RNA. The RNA can be directly functional or be the intermediate template for a protein that performs a function. The transmission of genes to an organism's offspring is the basis of the inheritance of phenotypic traits. These genes make up different DNA sequences called genotypes. Genotypes along with environmental and developmental factors determine what the phenotypes will be. Most biological traits are under the influence of polygenes (many different genes) as well as gen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nucleotide
Nucleotides are organic molecules consisting of a nucleoside and a phosphate. They serve as monomeric units of the nucleic acid polymers – deoxyribonucleic acid (DNA) and ribonucleic acid (RNA), both of which are essential biomolecules within all life-forms on Earth. Nucleotides are obtained in the diet and are also synthesized from common nutrients by the liver. Nucleotides are composed of three subunit molecules: a nucleobase, a five-carbon sugar (ribose or deoxyribose), and a phosphate group consisting of one to three phosphates. The four nucleobases in DNA are guanine, adenine, cytosine and thymine; in RNA, uracil is used in place of thymine. Nucleotides also play a central role in metabolism at a fundamental, cellular level. They provide chemical energy—in the form of the nucleoside triphosphates, adenosine triphosphate (ATP), guanosine triphosphate (GTP), cytidine triphosphate (CTP) and uridine triphosphate (UTP)—throughout the cell for the many cellular func ... [...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 RN ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Amino Acid
Amino acids are organic compounds that contain both amino and carboxylic acid functional groups. Although hundreds of amino acids exist in nature, by far the most important are the alpha-amino acids, which comprise proteins. Only 22 alpha amino acids appear in the genetic code. Amino acids can be classified according to the locations of the core structural functional groups, as Alpha and beta carbon, alpha- , beta- , gamma- or delta- amino acids; other categories relate to Chemical polarity, polarity, ionization, and side chain group type (aliphatic, Open-chain compound, acyclic, aromatic, containing hydroxyl or sulfur, etc.). In the form of proteins, amino acid '' residues'' form the second-largest component (water being the largest) of human muscles and other tissues. Beyond their role as residues in proteins, amino acids participate in a number of processes such as neurotransmitter transport and biosynthesis. It is thought that they played a key role in enabling life ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
