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Cypovirus
''Cypovirus'', short for cytoplasmic polyhedrosis virus, is a genus of double-stranded RNA viruses in the order ''Reovirales'' and family '' Spinareoviridae'', isolated solely from insects. Associated diseases include chronic diarrhoea and pale blue iridescence in the guts of larvae. It contains sixteen species. Cypoviruses are structurally similar to the more widely studied nucleopolyhedroviruses, a genus of arthropodean viruses in the family ''Baculoviridae'', except for their RNA genomes and cytoplasmic replication instead of DNA genomes and nucleic replication. Structure Viruses in the genus ''Cypovirus'' are nonenveloped, with icosahedral geometries, and T=2 symmetry. Cypoviruses have only a single capsid shell, which is similar to the orthoreovirus inner core. They exhibit striking capsid stability, which is fully capable of endogenous RNA transcription and processing. The capsid diameter is around 65 nm. Genome Genomes are linear and segmented. The genome codes ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ultrastructure
Ultrastructure (or ultra-structure) is the architecture of cells and biomaterials that is visible at higher magnifications than found on a standard optical light microscope. This traditionally meant the resolution and magnification range of a conventional transmission electron microscope (TEM) when viewing biological specimens such as cells, tissue, or organs. Ultrastructure can also be viewed with scanning electron microscopy and super-resolution microscopy, although TEM is a standard histology technique for viewing ultrastructure. Such cellular structures as organelles, which allow the cell to function properly within its specified environment, can be examined at the ultrastructural level. Ultrastructure, along with molecular phylogeny, is a reliable phylogenetic way of classifying organisms. Features of ultrastructure are used industrially to control material properties and promote biocompatibility. History In 1931, German engineers Max Knoll and Ernst Ruska invente ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arthropod
Arthropods ( ) are invertebrates in the phylum Arthropoda. They possess an arthropod exoskeleton, exoskeleton with a cuticle made of chitin, often Mineralization (biology), mineralised with calcium carbonate, a body with differentiated (Metamerism (biology), metameric) Segmentation (biology), segments, and paired jointed appendages. In order to keep growing, they must go through stages of moulting, a process by which they shed their exoskeleton to reveal a new one. They form an extremely diverse group of up to ten million species. Haemolymph is the analogue of blood for most arthropods. An arthropod has an open circulatory system, with a body cavity called a haemocoel through which haemolymph circulates to the interior Organ (anatomy), organs. Like their exteriors, the internal organs of arthropods are generally built of repeated segments. They have ladder-like nervous systems, with paired Anatomical terms of location#Dorsal and ventral, ventral Ventral nerve cord, nerve cord ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Betairidovirinae
''Betairidovirinae'' is a subfamily of viruses in the family ''Iridoviridae'' that was established in 2016. It is one of two subfamilies within this family, the other being '' Alphairdovirinae''. Most species within the ''Betairidovirinae'' are hosted by invertebrates, whereas all species within the ''Alphairdovirinae'' are hosted by ' cold-blooded' vertebrates (namely; fishes, amphibians, and reptiles). As such, viruses in this subfamily may be called invertebrate iridescent viruses (IIVs) or invertebrate iridoviruses. Genera The genus consists of the following four genera, although many additional putative and partially characterised taxa are known: * '' Chloriridovirus'' * '' Daphniairidovirus'' * '' Decapodiridovirus'' * '' Iridovirus'' Hosts The ''Betairidovirinae'' are hosted by invertebrates, but some research indicates they may hosted by vertebrates, and that at least one invertebrate-hosted iridovirus is actually more closely related to the ''Alphairdovirinae''. Mos ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lambda Phage
Lambda phage (coliphage λ, scientific name ''Lambdavirus lambda'') is a bacterial virus, or bacteriophage, that infects the bacterial species ''Escherichia coli'' (''E. coli''). It was discovered by Esther Lederberg in 1950. The wild type of this virus has a Temperate (virology), temperate life cycle that allows it to either reside within the genome of its host through lysogeny or enter into a lytic phase, during which it kills and lyses the cell to produce offspring. Lambda strains, mutated at specific sites, are unable to lysogenize cells; instead, they grow and enter the lytic cycle after superinfecting an already lysogenized cell. The phage particle consists of a head (also known as a capsid), a tail, and tail fibers (see image of virus below). The head contains the phage's double-strand linear DNA genome. During infections, the phage particle recognizes and binds to its host, ''E. coli'', causing DNA in the head of the phage to be ejected through the tail into the cytopla ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Helix
A helix (; ) is a shape like a cylindrical coil spring or the thread of a machine screw. It is a type of smooth space curve with tangent lines at a constant angle to a fixed axis. Helices are important in biology, as the DNA molecule is formed as two intertwined helices, and many proteins have helical substructures, known as alpha helices. The word ''helix'' comes from the Greek word , "twisted, curved". A "filled-in" helix – for example, a "spiral" (helical) ramp – is a surface called a '' helicoid''. Properties and types The pitch of a helix is the height of one complete helix turn, measured parallel to the axis of the helix. A double helix consists of two (typically congruent) helices with the same axis, differing by a translation along the axis. A circular helix (i.e. one with constant radius) has constant band curvature and constant torsion. The slope of a circular helix is commonly defined as the ratio of the circumference of the circular cylinder that it ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Methylase
Methyltransferases are a large group of enzymes that all methylate their substrates but can be split into several subclasses based on their structural features. The most common class of methyltransferases is class I, all of which contain a Rossmann fold for binding ''S''-Adenosyl methionine (SAM). Class II methyltransferases contain a SET domain, which are exemplified by SET domain histone methyltransferases, and class III methyltransferases, which are membrane associated. Methyltransferases can also be grouped as different types utilizing different substrates in methyl transfer reactions. These types include protein methyltransferases, DNA/RNA methyltransferases, natural product methyltransferases, and non-SAM dependent methyltransferases. SAM is the classical methyl donor for methyltransferases, however, examples of other methyl donors are seen in nature. The general mechanism for methyl transfer is a SN2-like nucleophilic attack where the methionine sulfur serves as the l ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Electrophoresis
Electrophoresis is the motion of charged dispersed particles or dissolved charged molecules relative to a fluid under the influence of a spatially uniform electric field. As a rule, these are zwitterions with a positive or negative net charge. Electrophoresis is used in laboratories to separate macromolecules based on their charges. The technique normally applies a negative charge called cathode so anionic protein molecules move towards a positive charge called anode. Therefore, electrophoresis of positively charged particles or molecules (cations) is sometimes called cataphoresis, while electrophoresis of negatively charged particles or molecules (anions) is sometimes called anaphoresis. Electrophoresis is the basis for analytical techniques used in biochemistry and molecular biology to separate particles, molecules, or ions by size, charge, or binding affinity, either freely or through a supportive medium using a one-directional flow of electrical charge. It is use ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Orthoreovirus
''Orthoreovirus'' is a genus of viruses, in the family ''Reoviridae'', in the subfamily ''Spinareovirinae''. Vertebrates serve as natural hosts. There are ten species in this genus. Diseases associated with this genus include mild upper respiratory tract disease, gastroenteritis, and biliary atresia. Mammalian orthoreovirus 3 (strain dearing-T3D) induces cell death preferentially in transformed cells and therefore displays inherent oncolytic properties. History The name "orthoreovirus" comes from the Greek word ''ortho'', meaning "straight" and the reovirus, which comes from taking the letters: R, E, and O from "respiratory enteric orphan virus". The Orthoreovirus was named an orphan virus because it was not known to be associated with any known disease. It was discovered in the early 1950s when it was isolated from the respiratory as well as gastrointestinal tracts of both sick and healthy individuals Classification ''Orthoreovirus'' is part of the family ''Reoviridae''. Its ge ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Capsid
A capsid is the protein shell of a virus, enclosing its genetic material. It consists of several oligomeric (repeating) structural subunits made of protein called protomers. The observable 3-dimensional morphological subunits, which may or may not correspond to individual proteins, are called capsomeres. The proteins making up the capsid are called capsid proteins or viral coat proteins (VCP). The virus genomic component inside the capsid, along with occasionally present virus core protein, is called the virus core. The capsid and core together are referred to as a nucleocapsid (cf. also virion). Capsids are broadly classified according to their structure. The majority of the viruses have capsids with either helical or icosahedral structure. Some viruses, such as bacteriophages, have developed more complicated structures due to constraints of elasticity and electrostatics. The icosahedral shape, which has 20 equilateral triangular faces, approximates a sphere, while th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Viral Envelope
A viral envelope is the outermost layer of many types of viruses. It protects the genetic material in their life cycle when traveling between host cells. Not all viruses have envelopes. A viral envelope protein or E protein is a protein in the envelope, which may be acquired by the capsid from an infected host cell. Host cell infection process Numerous human pathogenic viruses in circulation are encased in lipid bilayers, and they infect their target cells by causing the viral envelope and cell membrane to fuse. Although there are effective vaccines against some of these viruses, there is no preventative or curative medicine for the majority of them. In most cases, the known vaccines operate by inducing antibodies that prevent the pathogen from entering cells. This happens in the case of enveloped viruses when the antibodies bind to the viral envelope proteins. The membrane fusion event that triggers viral entrance is caused by the viral membrane fusion protein. Many envelo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Baculoviridae
''Baculoviridae'' is a family of viruses. Arthropods, among the most studied being Lepidoptera, Hymenoptera and Diptera, serve as natural hosts. Currently, 85 Virus classification, species are placed in this family, assigned to four genera. Baculoviruses are known to infect insects, with over 600 host species having been described. Immature (larval) forms of lepidopteran species (moths and butterflies) are the most common hosts, but these viruses have also been found infecting sawfly, sawflies, and mosquitoes. Although baculoviruses are capable of entering mammalian cells in culture, they are not known to be capable of replication in mammalian or other vertebrate animal cells. Starting in the 1940s, they were used and studied widely as biopesticides in crop fields. Baculoviruses contain a cccDNA, circular, double-stranded DNA, double-stranded DNA (dsDNA) genome ranging from 80 to 180 Base pair#Length measurements, kbp. Historical influence The earliest records of baculoviruses ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
