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Microviridae
''Microviridae'' is a family of bacteriophages with a single-stranded DNA genome. The name of this family is derived from the ancient Greek word (), meaning "small". This refers to the size of their genomes, which are among the smallest of the DNA viruses. Enterobacteria, intracellular parasitic bacteria, and spiroplasma serve as natural hosts. There are 22 species in this family, divided among seven genera and two subfamilies. Virology The virions are non-enveloped, round with an icosahedral symmetry (T = 1). They have a diameter between 25–27 nanometers and lack tails. Each virion has 60 copies each of the F, G, and J proteins and 12 copies of the H protein. They have 12 pentagonal trumpet-shaped pentamers (~7.1 nm wide × 3.8 nm high), each of which is composed of 5 copies of the G and one of the H protein. Viruses in this family replicate their genomes via a rolling circle mechanism and encode dedicated RCR initiation proteins.Keegstra W, Baas PD, Jansz HS (197 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bullavirinae
''Bullavirinae'' is a subfamily of viruses in the family '' Microviridae''. Enterobacteria Enterobacteriaceae is a large family of Gram-negative bacteria. It was first proposed by Rahn in 1936, and now includes over 30 genera and more than 100 species. Its classification above the level of family is still a subject of debate, but on ... serve as natural hosts. There are 14 species in this subfamily, organized into three genera. Taxonomy The following genera and species are recognized: * Genus: '' Alphatrevirus''; species: ** '' Escherichia virus alpha3'' ** '' Escherichia virus ID21'' ** '' Escherichia virus ID32'' ** '' Escherichia virus ID62'' ** '' Escherichia virus NC28'' ** '' Escherichia virus NC29'' ** '' Escherichia virus NC35'' ** '' Escherichia virus phiK'' ** '' Escherichia virus St1'' ** '' Escherichia virus WA45'' * Genus: '' Gequatrovirus''; species: ** '' Escherichia virus G4'' ** '' Escherichia virus ID52 '' ** '' Escherichia virus Talmos'' * Genus: '' Sinsh ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gokushovirinae
''Gokushovirinae'' is a subfamily of viruses in the family ''Microviridae''. There are 8 species in this subfamily, divided among 4 genera. Species and genera The following species and genera are assigned to the family: * Genus: ''Bdellomicrovirus'' ** '' Bdellovibrio virus MAC1'' ** '' Bdellovibrio virus MH2K'' * Genus: '' Chlamydiamicrovirus'' ** '' Chlamydia virus Chp1'' ** '' Chlamydia virus Chp2'' ** '' Chlamydia virus CPAR39'' ** '' Chlamydia virus CPG1'' * Genus: '' Enterogokushovirus'' ** '' Enterogokushovirus EC6098'' * Genus: ''Spiromicrovirus ''Spiromicrovirus'' is a genus of viruses, in the family ''Microviridae'', in the subfamily ''Gokushovirinae ''Gokushovirinae'' is a subfamily of viruses in the family ''Microviridae ''Microviridae'' is a family of bacteriophages with a ...'' ** '' Spiroplasma virus SpV4'' References External links ICTV {{Taxonbar, from=Q18812371 Microviridae Virus subfamilies ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spiromicrovirus
''Spiromicrovirus'' is a genus of viruses, in the family '' Microviridae'', in the subfamily ''Gokushovirinae ''Gokushovirinae'' is a subfamily of viruses in the family ''Microviridae''. There are 8 species in this subfamily, divided among 4 genera. Species and genera The following species and genera are assigned to the family: * Genus: ''Bdellomicrov ...''. Spiroplasma bacteria serve as natural hosts. There is only one species in this genus: ''Spiroplasma virus SpV4''. Structure Viruses in ''Spiromicrovirus'' are non-enveloped, with icosahedral and round geometries, and T=1 symmetry. The diameter is around 30 nm. Genomes are circular, around 6.1kb in length. Life cycle Viral replication is cytoplasmic. Entry into the host cell is achieved by pilus-mediated adsorption into the host cell. Replication follows the ssDNA rolling circle model. DNA-templated transcription is the method of transcription. The virus exits the host cell by bacteria lysis. Spiroplasma bacte ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chlamydiamicrovirus
''Chlamydiamicrovirus'' is a genus of viruses, in the family '' Microviridae'', in the subfamily ''Gokushovirinae''. Various species of chlamidia Chlamydia, or more specifically a chlamydia infection, is a sexually transmitted infection caused by the bacterium ''Chlamydia trachomatis''. Most people who are infected have no symptoms. When symptoms do appear they may occur only several wee ... serve as natural hosts. There are four species in this genus. Taxonomy The following species are assigned to the genus: * '' Chlamydia virus Chp1'' * '' Chlamydia virus Chp2'' * '' Chlamydia virus CPAR39'' * '' Chlamydia virus CPG1'' Structure Viruses in ''Chlamydiamicrovirus'' are non-enveloped, with icosahedral and round geometries, and T=1 symmetry. The diameter is around 30 nm. Genomes are circular, around 6.1kb in length. Life cycle Viral replication is cytoplasmic. Entry into the host cell is achieved by pilus-mediated adsorption into the host cell. Replication follows t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bacteriophage
A bacteriophage (), also known informally as a ''phage'' (), is a duplodnaviria virus that infects and replicates within bacteria and archaea. The term was derived from "bacteria" and the Greek φαγεῖν ('), meaning "to devour". Bacteriophages are composed of proteins that encapsulate a DNA or RNA genome, and may have structures that are either simple or elaborate. Their genomes may encode as few as four genes (e.g. MS2) and as many as hundreds of genes. Phages replicate within the bacterium following the injection of their genome into its cytoplasm. Bacteriophages are among the most common and diverse entities in the biosphere. Bacteriophages are ubiquitous viruses, found wherever bacteria exist. It is estimated there are more than 1031 bacteriophages on the planet, more than every other organism on Earth, including bacteria, combined. Viruses are the most abundant biological entity in the water column of the world's oceans, and the second largest component of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bdellomicrovirus
''Bdellomicrovirus'' is a genus of viruses, in the family ''Microviridae'', in the subfamily '' Gokushovirinae''. ''Bdellovibrio ''Bdellovibrio'' is a genus of Gram-negative, obligate aerobic bacteria. One of the more notable characteristics of this genus is that members can prey upon other Gram-negative bacteria and feed on the biopolymers, e.g. proteins and nucleic acid ...'' bacteria serve as natural hosts. There are two species in this genus. Structure Viruses in ''Bdellomicrovirus'' are non-enveloped, with icosahedral and Round geometries, and T=1 symmetry. The diameter is around 30 nm. Genomes are circular, around 4.5kb in length. Life cycle Viral replication is cytoplasmic. Entry into the host cell is achieved by pilus-mediated adsorption into the host cell. Replication follows the ssDNA rolling circle model. DNA templated transcription is the method of transcription. The virus exits the host cell by bacteria lysis. ''Bdellovibrio'' bacteria serve as the natur ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
DNA Polymerase
A DNA polymerase is a member of a family of enzymes that catalyze the synthesis of DNA molecules from nucleoside triphosphates, the molecular precursors of DNA. These enzymes are essential for DNA replication and usually work in groups to create two identical DNA duplexes from a single original DNA duplex. During this process, DNA polymerase "reads" the existing DNA strands to create two new strands that match the existing ones. These enzymes catalyze the chemical reaction : deoxynucleoside triphosphate + DNAn pyrophosphate + DNAn+1. DNA polymerase adds nucleotides to the three prime (3')-end of a DNA strand, one nucleotide at a time. Every time a cell divides, DNA polymerases are required to duplicate the cell's DNA, so that a copy of the original DNA molecule can be passed to each daughter cell. In this way, genetic information is passed down from generation to generation. Before replication can take place, an enzyme called helicase unwinds the DNA molecule from its t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Clades
A clade (), also known as a monophyletic group or natural group, is a group of organisms that are monophyletic – that is, composed of a common ancestor and all its lineal descendants – on a phylogenetic tree. Rather than the English term, the equivalent Latin term ''cladus'' (plural ''cladi'') is often used in taxonomical literature. The common ancestor may be an individual, a population, or a species ( extinct or extant). Clades are nested, one in another, as each branch in turn splits into smaller branches. These splits reflect evolutionary history as populations diverged and evolved independently. Clades are termed monophyletic (Greek: "one clan") groups. Over the last few decades, the cladistic approach has revolutionized biological classification and revealed surprising evolutionary relationships among organisms. Increasingly, taxonomists try to avoid naming taxa that are not clades; that is, taxa that are not monophyletic. Some of the relationships between organ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
RNA Polymerase
In molecular biology, RNA polymerase (abbreviated RNAP or RNApol), or more specifically DNA-directed/dependent RNA polymerase (DdRP), is an enzyme that synthesizes RNA from a DNA template. Using the enzyme helicase, RNAP locally opens the double-stranded DNA so that one strand of the exposed nucleotides can be used as a template for the synthesis of RNA, a process called transcription. A transcription factor and its associated transcription mediator complex must be attached to a DNA binding site called a promoter region before RNAP can initiate the DNA unwinding at that position. RNAP not only initiates RNA transcription, it also guides the nucleotides into position, facilitates attachment and elongation, has intrinsic proofreading and replacement capabilities, and termination recognition capability. In eukaryotes, RNAP can build chains as long as 2.4 million nucleotides. RNAP produces RNA that, functionally, is either for protein coding, i.e. messenger RNA (mRNA); ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pilot Protein
An aircraft pilot or aviator is a person who controls the flight of an aircraft by operating its directional flight controls. Some other aircrew members, such as navigators or flight engineers, are also considered aviators, because they are involved in operating the aircraft's navigation and engine systems. Other aircrew members, such as drone operators, flight attendants, mechanics and ground crew, are not classified as aviators. In recognition of the pilots' qualifications and responsibilities, most militaries and many airlines worldwide award aviator badges to their pilots. History The first recorded use of the term ''aviator'' (''aviateur'' in French) was in 1887, as a variation of ''aviation'', from the Latin ''avis'' (meaning ''bird''), coined in 1863 by in ''Aviation Ou Navigation Aérienne'' ("Aviation or Air Navigation"). The term ''aviatrix'' (''aviatrice'' in French), now archaic, was formerly used for a female aviator. These terms were used more in the ea ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Occitan Language
Occitan (; oc, occitan, link=no ), also known as ''lenga d'òc'' (; french: langue d'oc) by its native speakers, and sometimes also referred to as ''Provençal'', is a Romance language spoken in Southern France, Monaco, Italy's Occitan Valleys, as well as Spain's Val d'Aran; collectively, these regions are sometimes referred to as Occitània. It is also spoken in Calabria ( Southern Italy) in a linguistic enclave of Cosenza area (mostly Guardia Piemontese). Some include Catalan in Occitan, as the distance between this language and some Occitan dialects (such as the Gascon language) is similar to the distance between different Occitan dialects. Catalan was considered a dialect of Occitan until the end of the 19th century and still today remains its closest relative. Occitan is an official language of Catalonia, where a subdialect of Gascon known as Aranese is spoken in the Val d'Aran. Since September 2010, the Parliament of Catalonia has considered Aranese Occitan to be ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Prophages
A prophage is a bacteriophage (often shortened to "phage") genome that is integrated into the circular bacterial chromosome or exists as an extrachromosomal plasmid within the bacterial cell. Integration of prophages into the bacterial host is the characteristic step of the lysogenic cycle of temperate phages. Prophages remain latent in the genome through multiple cell divisions until activation by an external factor, such as UV light, leading to production of new phage particles that will lyse the cell and spread. As ubiquitous mobile genetic elements, prophages play important roles in bacterial genetics and evolution, such as in the acquisition of virulence factors. Background Prophages are able to do a multitude of things within their respective bacterial strains. Prophages can increase the virulence potential of bacterial strains in both humans and plant pathogens as well as increase the ability of the bacteria to survive in harsh environments. Pathogens have been able to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
