Siphoviridae | |
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TME picture of an Escherichia virus HK97 virion, Siphoviridae | |
Virus classification | |
(unranked): | Virus |
Realm: | Duplodnaviria |
Kingdom: | Heunggongvirae |
Phylum: | Uroviricota |
Class: | Caudoviricetes |
Order: | Caudovirales |
Family: | Siphoviridae |
Genera | |
Synonyms [1] | |
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Siphoviridae was a family of double-stranded DNA viruses in the order Caudovirales . The family Siphoviridae and order Caudovirales have now been abolished, with the term siphovirus now used to refer to the morphology of viruses in this former family. Bacteria and archaea serve as natural hosts. The family had 1,166 species, assigned to 366 genera and 22 subfamilies. [2] [3] The characteristic structural features are a non-enveloped head and non-contractile tail.
Viruses in the former family Siphoviridae are non-enveloped, with icosahedral and head-tail geometries [2] (morphotype B1) or a prolate capsid (morphotype B2), and T=7 symmetry. Their diameters are around 60 nm. [2] Members of this family are also characterized by their filamentous, cross-banded, non-contractile tails, usually with short terminal and subterminal fibers. Genomes are double stranded and linear, around 50 kb in length, [2] containing about 70 genes. The guanine/cytosine content is usually around 52%.[ citation needed ]
Viral replication is cytoplasmic. Entry into the host cell is achieved by adsorption into the host cell. Replication follows the replicative transposition model. DNA-templated transcription is the method of transcription. Translation takes place by -1 ribosomal frameshifting, and +1 ribosomal frameshifting. The virus exits the host cell by lysis, and holin, endolysin, or spanin proteins. [2] Bacteria and archaea serve as the natural host. Transmission routes are passive diffusion. [2]
The following subfamilies are recognized: [3]
The following genera are unassigned to a subfamily: [3]
Please note that genus Inceonvirus is likely misspelled Incheonvirus.
Myoviridae was a family of bacteriophages in the order Caudovirales. The family Myoviridae and order Caudovirales have now been abolished, with the term myovirus now used to refer to the morphology of viruses in this former family. Bacteria and archaea serve as natural hosts. There were 625 species in this family, assigned to eight subfamilies and 217 genera.
Podoviridae was a family of bacteriophage in the order Caudovirales often associated with T-7 like phages. The family and order Caudoviraleshave now been abolished, with the term podovirus now used to refer to the morphology of viruses in this former family. There were 130 species in this family, assigned to 3 subfamilies and 52 genera. This family was characterized by having very short, noncontractile tails. Many former phages in the former family Podoviriade are now classified in the Autographiviridae
Totiviridae is a family of double-stranded RNA viruses. Giardia lamblia, leishmania, trichomonas vaginalis, and fungi serve as natural hosts. The name of the group derives from Latin toti which means undivided or whole. There are 28 species in this family, assigned to 5 genera.
Barnaviridae is a family of non-enveloped, positive-strand RNA viruses. Cultivated mushrooms serve as natural hosts. The family has one genus, Barnavirus, which contains one species: Mushroom bacilliform virus. Diseases associated with this family includes La France disease.
Caudoviricetes is a class of viruses known as the tailed bacteriophages. Under the Baltimore classification scheme, the Caudoviricetes are group I viruses as they have double stranded DNA (dsDNA) genomes, which can be anywhere from 18,000 base pairs to 500,000 base pairs in length. The virus particles have a distinct shape; each virion has an icosahedral head that contains the viral genome, and is attached to a flexible tail by a connector protein. The order encompasses a wide range of viruses, many containing genes of similar nucleotide sequence and function. However, some tailed bacteriophage genomes can vary quite significantly in nucleotide sequence, even among the same genus. Due to their characteristic structure and possession of potentially homologous genes, it is believed these bacteriophages possess a common origin.
Baltimore classification is a system used to classify viruses based on their manner of messenger RNA (mRNA) synthesis. By organizing viruses based on their manner of mRNA production, it is possible to study viruses that behave similarly as a distinct group. Seven Baltimore groups are described that take into consideration whether the viral genome is made of deoxyribonucleic acid (DNA) or ribonucleic acid (RNA), whether the genome is single- or double-stranded, and whether the sense of a single-stranded RNA genome is positive or negative.
Picovirinae is a subfamily of viruses in the order Caudovirales, in the family Salasmaviridae. Bacteria serve as natural hosts. There are two genera and seven species in this subfamily.
Uetakevirus is a genus of viruses in the order Caudovirales, in the family Podoviridae. Bacteria serve as natural hosts. There are three species in this genus. These phages are temperate and infect Salmonella and Escherichia coli.
Okubovirus is a genus of viruses in the order Caudovirales, in the family Herelleviridae, in the subfamily Spounavirinae. Bacteria serve as natural hosts. There are two species in this genus.
Spounavirinae is a subfamily of viruses in the order Caudovirales, in the family Herelleviridae. Bacteria serve as natural hosts. There are currently five species in this subfamily, divided among 2 genera.
Tevenvirinae is a subfamily of viruses in the family Straboviridae of class Caudoviricetes. The subfamily was previously placed in the morphology-based family Myoviridae, which was found to be paraphyletic in genome studies and abolished in the 2021 International Committee on Taxonomy of Viruses (ICTV) classification. Bacteria and archaea serve as natural hosts. There are 148 species in this subfamily, included in 14 genera.
Muvirus is a genus of viruses in the order Caudovirales, in the family Myoviridae. Bacteria serve as natural hosts, with transmission achieved through passive diffusion. There are two species in this genus.
Myohalovirus is a genus of viruses in the order Caudovirales, in the family Myoviridae. Bacteria and archaea serve as natural hosts. There are three species in this genus.
Salasvirus is a genus of viruses in the order Caudovirales, in the family Salasmaviridae, in the subfamily Picovirinae. Bacteria serve as natural hosts. There are four species in this genus.
Ceduovirus is a genus of viruses in the family Siphoviridae, unassigned to a sub-family. Bacteria serve as the natural host, with transmission achieved through passive diffusion. There are 34 species in this genus.
Lambdavirus is a genus of viruses in the order Caudovirales, in the family Siphoviridae. Bacteria serve as natural hosts, with transmission achieved through passive diffusion. There are five species in this genus. The genus also includes several unclassified viruses—including the corynephages β and ω, which infect Corynebacterium diphtheriae and carry the deadly diphtheria toxin.
Ravinvirus is a genus of viruses in the order Caudovirales, in the family Siphoviridae. Bacteria serve as natural hosts, with transmission achieved through passive diffusion. There is only one species in this genus: Escherichia virus N15.
Lomovskayavirus is a genus of viruses in the order Caudovirales, in the family Siphoviridae. Bacteria serve as natural hosts. There are two species in this genus.
Spbetavirus is a genus of viruses in the order Caudovirales, in the family Siphoviridae. Bacteria serve as natural hosts. There is only one species in this genus: Bacillus virus SPbeta.
Tunavirus is a genus of viruses in the order Caudovirales, in the family Drexlerviridae. Bacteria serve as natural hosts. There are currently 14 species in this genus, including the type species Escherichia virus T1.