Halorubrum pleomorphic virus 1 (HRPV-1) is a single stranded DNA virus that infects the species of the

archaea Archaea ( ; singular archaeon ) is a domain of single-celled organisms. These microorganisms lack cell nuclei and are therefore prokaryotes. Archaea were initially classified as bacteria, receiving the name archaebacteria (in the Archaeba ...

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of living and fossil organisms as well as viruses. In the hierarchy of biological classification, genus comes above species and below family. In binomial nom ...

Halorubrum ''Halorubrum'' is a genus in the family Halorubraceae. ''Halorubrum'' species areusually halophilic and can be found in waters with high salt concentration such as the Dead Sea or Lake Zabuye. Genetic exchange A population of the haloarchaea ' ...

''.Pietila, M, Laurinavicius S, Sund, J, Roine E & Bamford D (2009) The single-stranded DNA genome of novel archaeal virus Halorubrum pleomorphic virus 1 Is enclosed in the envelope decorated with glycoprotein spikes. J Virol 84 (2) 788-798 It is unlike any other known virus infecting the archaea with a single stranded DNA genome and an external lipid envelope and is classified in the family ''Pleolipoviridae'', genus ''Alphapleolipovirus'', species ''Halorubrum virus HRPV1''. __TOC__

Virology

The virons are pleomorphic is shape with an external lipd envelope. There are two main structural proteins (VP3 and VP4) of molecular weights 15 and 53 kiloDaltons respectively. The genome does not appear to be associated with a nucleoprotein. The spike protein (VP4) is glycosylated. The lipid envelope is similar to its host's composition. VP3 is a membrane protein that does not appears to be exposed to the external environment. It may be organised to form a shell around the genome as is the case in other viruses but this is not yet known. This virus infects members of the genus ''Halorubrum''. Infection appears to be productive without lysis of the host like may of the archaeal viruses. Exit is likely to be by budding from the cell membrane.

Genome

The genome is a single stranded DNA molecule 7048 bases in length. It encodes nine

open reading frame In molecular biology, open reading frames (ORFs) are defined as spans of DNA sequence between the start and stop codons. Usually, this is considered within a studied region of a prokaryotic DNA sequence, where only one of the six possible readi ...

s. Two of these encode the structural proteins VP3 and VP4. Another (VP8) seems likely to be an

ATPase ATPases (, Adenosine 5'-TriPhosphatase, adenylpyrophosphatase, ATP monophosphatase, triphosphatase, SV40 T-antigen, ATP hydrolase, complex V (mitochondrial electron transport), (Ca2+ + Mg2+)-ATPase, HCO3−-ATPase, adenosine triphosphatase) are ...

. The functions of the remaining proteins is not known.

References

{{Taxonbar, from=Q5643445 Single-stranded DNA viruses Archaeal viruses