 | It has been suggested that this article be merged into Gammatorquevirus . (Discuss) Proposed since March 2020. |
| Torque teno midi virus | |
|---|---|
| Virus classification | |
| Group: | Group II (ssDNA) |
| Family: | |
| Genus: | |
| Species | |
Transfusion Transmitted Virus | |
Torque teno midi virus (TTMDV) is a member of the genus Gammatorquevirus in the family Anelloviridae .
TTMDV, which stands for transfusion transmitted midi virus or torque teno midi virus was first isolated in 2005 from patients with an acute viral infection syndrome. [1]
Because of the circular nature of its DNA genome, TTMDV (which was provisionally named small anellovirus 1) was classified as an anellovirus. Genomic analysis confirmed this classification. [2]
Like other anelloviruses, TTMDV is quite common, even in healthy individuals. It has been found in various bodily fluids, including saliva and nasopharyngeal aspirates.
Like other members of its family, TTMDV's genome is a circular single-stranded piece of DNA of a negative polarity. The genome is approximately 3.2 kb in length, which is slightly smaller than that of TTV and slightly larger than that of TTMV. it is a non-enveloped virus with a capsid of about 40 nm in diameter. The capsid possesses T=1 icosahedral symmetry.
The genomes of TTMDV, TTMV, and TTV are similar. The main differences are illustrated by Okamato[ who? ] 2009. [3]
The pathogenic effects of TTMDV in humans is not known. However, it has been isolated from diarrhea. [4]
A DNA virus is a virus that has DNA as its genetic material and replicates using a DNA-dependent DNA polymerase. The nucleic acid is usually double-stranded DNA (dsDNA) but may also be single-stranded DNA (ssDNA). DNA viruses belong to either Group I or Group II of the Baltimore classification system for viruses. Single-stranded DNA is usually expanded to double-stranded in infected cells. Although Group VII viruses such as hepatitis B contain a DNA genome, they are not considered DNA viruses according to the Baltimore classification, but rather reverse transcribing viruses because they replicate through an RNA intermediate. Notable diseases like smallpox, herpes, and the chickenpox are caused by such DNA viruses.
The Parvoviridae are a family of small, rugged, genetically-compact DNA viruses, known collectively as parvoviruses. There are currently more than 100 species in the family, divided among 23 genera in three subfamilies. Parvoviridae is the sole taxon in the order Quintoviricetes.
Hepadnaviridae is a family of viruses. Humans, apes, and birds serve as natural hosts. There are currently 18 species in this family, divided among 5 genera. Its best-known member is hepatitis B virus. Diseases associated with this family include: liver infections, such as hepatitis, hepatocellular carcinomas, and cirrhosis. It is the sole family in the order Blubervirales.
Polyomaviridae is a family of viruses whose natural hosts are primarily mammals and birds. As of 2019, there are four recognized genera and 102 species, nine of which are unassigned to a genus. 14 species are known to infect humans, while others, such as Simian Virus 40, have been identified in humans to a lesser extent. Most of these viruses are very common and typically asymptomatic in most human populations studied. BK virus is associated with nephropathy in renal transplant and non-renal solid organ transplant patients, JC virus with progressive multifocal leukoencephalopathy, and Merkel cell virus with Merkel cell cancer.
Kaposi's sarcoma-associated herpesvirus (KSHV) is the ninth known human herpesvirus; its formal name according to the International Committee on Taxonomy of Viruses (ICTV) is Human gammaherpesvirus 8, or HHV-8 in short. Like other herpesviruses, its informal names are used interchangeably with its formal ICTV name. This virus causes Kaposi's sarcoma, a cancer commonly occurring in AIDS patients, as well as primary effusion lymphoma, HHV-8-associated multicentric Castleman's disease and KSHV inflammatory cytokine syndrome. It is one of seven currently known human cancer viruses, or oncoviruses. Even after so many years of discovery of KSHV/HHV8, there is no known cure for KSHV associated tumorigenesis.
Circoviridae is a family of viruses. Birds and mammals serve as natural hosts. There are currently 94 species in this family, divided among 2 genera. Diseases associated with this family include: PCV-2: postweaning multisystemic wasting syndrome; CAV: chicken infectious anemia.
TT virus (TTV) was the first member of the new family Anelloviridae to be discovered.
Virus latency is the ability of a pathogenic virus to lie dormant (latent) within a cell, denoted as the lysogenic part of the viral life cycle. A latent viral infection is a type of persistent viral infection which is distinguished from a chronic viral infection. Latency is the phase in certain viruses' life cycles in which, after initial infection, proliferation of virus particles ceases. However, the viral genome is not fully eradicated. The result of this is that the virus can reactivate and begin producing large amounts of viral progeny without the host becoming reinfected by new outside virus, and stays within the host indefinitely.
Astroviruses are a type of virus that was first discovered in 1975 using electron microscopes following an outbreak of diarrhea in humans. In addition to humans, astroviruses have now been isolated from numerous mammalian animal species and from avian species such as ducks, chickens, and turkey poults. Astroviruses are 28–35 nm diameter, icosahedral viruses that have a characteristic five- or sixpointed star-like surface structure when viewed by electron microscopy. Along with the Picornaviridae and the Caliciviridae, the Astroviridae comprise a third family of nonenveloped viruses whose genome is composed of plus-sense, single-stranded RNA. Astrovirus has a non-segmented, single stranded, positive sense RNA genome within a non-enveloped icosahedral capsid. Human astroviruses have been shown in numerous studies to be an important cause of gastroenteritis in young children worldwide. In animals, Astroviruses also cause infection of the gastrointestinal tract but may also result in encephalitis, hepatitis (avian) and nephritis (avian).
Herpes simplex virus1 and 2, also known by their taxonomical names Human alphaherpesvirus 1 and Human alphaherpesvirus 2, are two members of the human Herpesviridae family, a set of new viruses that produce viral infections in the majority of humans. Both HSV-1 and HSV-2 are common and contagious. They can be spread when an infected person begins shedding the virus.
Anelloviridae is a family of viruses. They are classified as vertebrate viruses and have a non-enveloped capsid, which is round with isometric, icosahedral symmetry and has a triangulation number of 3.
A virus is a submicroscopic infectious agent that replicates only inside the living cells of an organism. Viruses can infect all types of life forms, from animals and plants to microorganisms, including bacteria and archaea. Since Dmitri Ivanovsky's 1892 article describing a non-bacterial pathogen infecting tobacco plants, and the discovery of the tobacco mosaic virus by Martinus Beijerinck in 1898, more than 6,000 virus species have been described in detail, of the millions of types of viruses in the environment. Viruses are found in almost every ecosystem on Earth and are the most numerous type of biological entity. The study of viruses is known as virology, a subspeciality of microbiology.
Human bocavirus (HBoV) is the name given to all viruses in the genus Bocaparvovirus of virus family Parvoviridae that are known to infect humans. HBoV1 and HBoV3 are members of species Primate bocaparvovirus 1 whereas viruses HBoV2 and HBoV4 belong to species Primate bocaparvovirus 2. Some of these viruses cause human disease. HBoV1 is strongly implicated in causing some cases of lower respiratory tract infection, especially in young children, and several of the viruses have been linked to gastroenteritis, although the full clinical role of this emerging infectious disease remains to be elucidated.
Lujo is a bisegmented RNA virus—a member of the family Arenaviridae—and a known cause of viral hemorrhagic fever (VHF) in humans. Its name was suggested by the Special Pathogens Unit of the National Institute for Communicable Diseases of the National Health Laboratory Service (NICD-NHLS) by using the first two letters of the names of the cities involved in the 2008 outbreak of the disease, Lusaka (Zambia) and Johannesburg. It is the second pathogenic Arenavirus to be described from the African continent—the first being Lassa virus—and since 2012 has been classed as a "Select Agent" under U.S. law.
Iotatorquevirus is a genus in the new family of Anelloviridae, in group II in the Baltimore classification. It encompasses two species of the Torque teno sus virus.
WU polyomavirus is a virus of the family Polyomaviridae. It was discovered in 2007 in samples of human respiratory secretions, originally from a child patient in Australia who presented with clinical signs of pneumonia and in whom other common respiratory viruses were not detected. Follow-up studies identified the presence of WU virus in respiratory secretion samples from patients in Australia and the United States, suggesting that, like other human polyomaviruses, WU virus is widely distributed.
Torque teno mini virus (TTMV) belongs to the Betatorquevirus genus of the family Anelloviridae. There are 12 species labelled Torque Teno mini virus 1–12. TTMV is the type species of Betatorquevirus and is one of the three human anelloviruses.
Minor capsid protein VP2 and minor capsid protein VP3 are viral proteins that are components of the polyomavirus capsid. Polyomavirus capsids are composed of three proteins; the major component is major capsid protein VP1, which self-assembles into pentamers that in turn self-assemble into enclosed icosahedral structures. The minor components are VP2 and VP3, which bind in the interior of the capsid.
Canine circovirus, first isolated in 2012, is a small non-enveloped, icosahedral, single-stranded DNA virus that infects domestic dogs and wild canids exclusively. It is a member of the Circoviridae family and the genus Circovirus. There are currently 11 species of known circoviruses that have been identified to affect a wide variety of birds and mammals. As seen with all extensively studied circoviruses, the diameter ranges between approximately 15 and 25 nanometers. The icosahedral triangulation number is 1, the smallest size a viral capsid can be, in which there are a total of 60 protein subunits that make up the capsid. CaCV is not to be confused with canine coronavirus, another diarrhea-causing agent within the family Coronaviridae, or porcine circoviruses which are a members of the same genus as CaCV but only seen in pigs. CaCV was the first Circovirus to be identified that infects a mammal species other than pigs.
Torque teno sus virus, belonging to the family Anelloviridae, is a group of virus strains that are non-enveloped, with a single-stranded circular DNA genome ranging from 2.6 to 2.8 kb in size. These swine infecting anelloviruses are divided into two genera: genus Iotatorquevirus (TTSuV1) and genus Kappatorquevirus (TTSuV2). Torque Teno Sus Virus has been found in pigs worldwide. TTSuVs are mainly transmitted by fecal-oral route. The prevalence of these viruses is relatively high. For now, there is not known disease caused exclusively by TTSuV. There is the possibility that TTSuV may worsen the progression of other diseases and therefore increase the economic losses for pig industry.