Coccolithovirus
Encyclopedia
Coccolithovirus is a genus of giant double-stranded DNA virus
that infect Emiliania huxleyi
, a species of coccolithophore
.
s are ~400 kilobase pairs in length with a G+C content of 41.1%. The genome contains ~470 predicted coding sequences. A third genome has been partly sequenced.
and Plymouth Marine Laboratory
(PML), first observed the virus in 1999. Later in the summer of 2005 researchers at the Plymouth Marine Laboratory
(Willie Wilson et al.) and at the Sanger Institute
(Holden et al.) sequenced the genome for the EhV-86 strain finding it to have 472 protein-coding genes making it a "giant-virus", and the largest known marine virus by genome.
From initial investigation of the Coccolithoviruses genome, a sequence of genes responsible for production of ceramide
was discovered . Ceramide is a controlling factor in cell death, and it is currently thought that Coccolithovirus uses this to prolong the life of Emiliania huxleyi
while it uses the host cell to replicate. This is a unique ability unseen in any other viral genome to date.
DNA virus
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 but may also be single-stranded DNA . DNA viruses belong to either Group I or Group II of the Baltimore classification system for viruses...
that infect Emiliania huxleyi
Emiliania huxleyi
Emiliania huxleyi, often abbreviated "EHUX", is a species of coccolithophore with a global distribution from the tropics to subarctic waters. It is one of thousands of different photosynthetic plankton that freely drift in the euphotic zone of the ocean, forming the basis of virtually all marine...
, a species of coccolithophore
Coccolithophore
Coccolithophores are single-celled algae, protists, and phytoplankton belonging to the division of haptophytes. They are distinguished by special calcium carbonate plates of uncertain function called coccoliths , which are important microfossils...
.
Genomes
Two genomes have been sequenced Emiliania huxleyi virus 86 and Emiliania huxleyi virus 203. The genomeGenome
In modern molecular biology and genetics, the genome is the entirety of an organism's hereditary information. It is encoded either in DNA or, for many types of virus, in RNA. The genome includes both the genes and the non-coding sequences of the DNA/RNA....
s are ~400 kilobase pairs in length with a G+C content of 41.1%. The genome contains ~470 predicted coding sequences. A third genome has been partly sequenced.
History
Wilson and his team at the Marine Biological Association (MBA), University of East AngliaUniversity of East Anglia
The University of East Anglia is a public research university based in Norwich, United Kingdom. It was established in 1963, and is a founder-member of the 1994 Group of research-intensive universities.-History:...
and Plymouth Marine Laboratory
Plymouth Marine Laboratory
Plymouth Marine Laboratory in the city of Plymouth, England is an independent collaborative centre of the Natural Environment Research Council . PML's Chairman is Terence Lewis and PML's Chief Executive is Prof. Stephen de Mora.They focus global issues of climate change and sustainability...
(PML), first observed the virus in 1999. Later in the summer of 2005 researchers at the Plymouth Marine Laboratory
Plymouth Marine Laboratory
Plymouth Marine Laboratory in the city of Plymouth, England is an independent collaborative centre of the Natural Environment Research Council . PML's Chairman is Terence Lewis and PML's Chief Executive is Prof. Stephen de Mora.They focus global issues of climate change and sustainability...
(Willie Wilson et al.) and at the Sanger Institute
Sanger Institute
The Wellcome Trust Sanger Institute is a non-profit, British genomics and genetics research institute, primarily funded by the Wellcome Trust....
(Holden et al.) sequenced the genome for the EhV-86 strain finding it to have 472 protein-coding genes making it a "giant-virus", and the largest known marine virus by genome.
From initial investigation of the Coccolithoviruses genome, a sequence of genes responsible for production of ceramide
Ceramide
Ceramides are a family of lipid molecules. A ceramide is composed of sphingosine and a fatty acid. Ceramides are found in high concentrations within the cell membrane of cells. They are one of the component lipids that make up sphingomyelin, one of the major lipids in the lipid bilayer...
was discovered . Ceramide is a controlling factor in cell death, and it is currently thought that Coccolithovirus uses this to prolong the life of Emiliania huxleyi
Emiliania huxleyi
Emiliania huxleyi, often abbreviated "EHUX", is a species of coccolithophore with a global distribution from the tropics to subarctic waters. It is one of thousands of different photosynthetic plankton that freely drift in the euphotic zone of the ocean, forming the basis of virtually all marine...
while it uses the host cell to replicate. This is a unique ability unseen in any other viral genome to date.
See also
- MimivirusMimivirusMimivirus is a viral genus containing a single identified species named Acanthamoeba polyphaga mimivirus , or is a group of phylogenetically related large viruses . In colloquial speech, APMV is more commonly referred to as just “mimivirus”...
- largest giant virus on record by genome - Mycoplasma genitaliumMycoplasma genitaliumMycoplasma genitalium is a small parasitic bacterium that lives on the ciliated epithelial cells of the primate genital and respiratory tracts. M. genitalium is the smallest known genome that can constitute a cell, and the second-smallest bacterium after the recently-discovered endosymbiont...
, Pelagibacter ubiquePelagibacter ubiquePelagibacter, with the single species P. ubique, was isolated in 2002 and given a specific name, although it has not yet been validly published according to the bacteriological code. It is an abundant member of the SAR11 clade in the phylum Alphaproteobacteria...
- some of the smallest known bacteria - NanoarchaeumNanoarchaeumNanoarchaeum equitans is a species of tiny microbe, discovered in 2002 in a hydrothermal vent off the coast of Iceland by Karl Stetter. Since it grows in temperatures approaching boiling, it is considered to be a thermophile. Nanoarchaeum appears to be an obligatory symbiont on the archaeon...
- smallest known archaeum - Smallest organisms
- ParvovirusParvovirusParvovirus, often truncated to "parvo", is both the common name in English casually applied to all the viruses in the Parvoviridae taxonomic family, and also the taxonomic name of the Parvovirus genus within the Parvoviridae family...
- smallest known family of virusVirusA virus is a small infectious agent that can replicate only inside the living cells of organisms. Viruses infect all types of organisms, from animals and plants to bacteria and archaea...
es - PhycodnaviridaePhycodnaviridaePhycodnaviruses are large , double stranded DNA viruses that infect marine or freshwater eukaryotic algae...
- algae infecting viruses
Further reading
- Wilson, W. H., Schroeder, D. C., Allen, M. J., Holden, M. T. G., Parkhill, J., Barrell, B. G., Churcher, C., Hamlin, N., Mungall, K., Norbertczak, H., Quail, M. A., Price, C., Rabbinowitsch, E., Walker, D., Craigon, M., Roy, D. and Ghazal, P. (2005) Complete Genome Sequence and Lytic Phase Transcription Profile of a Coccolithovirus. Science 5737, 1090-1092
- Allen, M. J., Schroeder, D. C., Holden, M. T. and Wilson, W. H. (2006) Evolutionary History of the Coccolithoviridae. Mol Biol Evol. 23, 86-92 (AthensAthens access and identity managementAthens is an Access and Identity Management service based in the United Kingdom that is supplied by Eduserv to provide single sign-on to protected resources combined with full user management capability...
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