Marseilleviridae | |
---|---|
Virus classification | |
(unranked): | Virus |
Realm: | Varidnaviria |
Kingdom: | Bamfordvirae |
Phylum: | Nucleocytoviricota |
Class: | Megaviricetes |
Order: | Pimascovirales |
Family: | Marseilleviridae |
Genera | |
Marseilleviridae is a family of viruses first named in 2012. [1] The genomes of these viruses are double-stranded DNA. Amoeba are often hosts, but there is evidence that they are found in humans as well. [2] [3] [4] [5] The family contains one genus and four species, two of which are unassigned to a genus. [6] [7] It is a member of the nucleocytoplasmic large DNA viruses clade.
The genus contains the following genera and species: [7]
Additional species have since been recognized. [1] The first member of this family recognized has been named Acanthamoeba polyphaga marseillevirus. A second member is Acanthamoeba castellanii lausannevirus. Two additional viruses have been isolated but have yet to be named. Another member of this family has been isolated from blood donors. [4] An isolate from insects—Insectomime virus—has also been reported. [8]
The viruses appear to fall into at least 3 lineages: (1) Marseillevirus and Cannes8virus (2) Insectomime and Tunisvirus and (3) Lausannevirus. A sixth potential member of this family—Melbournevirus—appears to be related to the Marseillevirus/Cannes8virus clade. [9]
A seventh virus—Brazilian Marseillevirus—has been reported. [10] This virus appears to belong to a fourth lineage of virus in this family.
Another virus—Tokyovirus—has also been reported. [11]
Another member of this family is Kurlavirus. [12]
In 2017, it was proposed that the family contained the following five lineages: [13]
Lineage A
Lineage B
Lineage C
Lineage D
Lineage E
Another putative member of this family is Marseillevirus shanghai. If this virus is confirmed, it would belong to the A lineage.
Viruses in Marseilleviridae have icosahedral geometries. The diameter is around 250 nm. Genomes are circular, around 372kb in length. The genome has 457 open reading frames. [6]
Genus | Structure | Symmetry | Capsid | Genomic arrangement | Genomic segmentation |
---|---|---|---|---|---|
Unassigned | Head-Tail | T=16 | Non-enveloped | Linear | Monopartite |
Marseillevirus | Icosahedral | Circular |
DNA-templated transcription is the method of transcription. Amoeba serve as the natural host. [6]
Genus | Host details | Tissue tropism | Entry details | Release details | Replication site | Assembly site | Transmission |
---|---|---|---|---|---|---|---|
Marseillevirus | Amoeba | None | Fusion | Lysis | Cytoplasm | Cytoplasm | Diffusion in Water |
A promoter sequence—AAATATTT—has been found associated with 55% of the identified genes in this virus. [14] Most of these sequences occur in multiple copies.[ citation needed ]
One of the first members of this family was described in 2009. [15] Other members described around then (2007) and since then have been documented. [16]
Mimivirus is a genus of giant viruses, in the family Mimiviridae. Amoeba serve as their natural hosts. This genus contains a single identified species named Acanthamoeba polyphaga mimivirus (APMV). It also refers to a group of phylogenetically related large viruses.
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Marseillevirus is a genus of viruses, in the family Marseilleviridae. There are two species in this genus. It is the prototype of a family of nucleocytoplasmic large DNA viruses (NCLDV) of eukaryotes. It was isolated from amoeba.
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