Lipothrixviridae

The virus family Lipothrixviridae ( gr λἷπος: fat, θρίξ: Hair ) comprises three genera of bacteriophages with linear, double-stranded DNA genome (dsDNA ). The Lipothrixviridae have a very long, helical capsid is surrounded by a very tight viral envelope.

The virions of Lipothrixviridae have, depending on the type of virus in thickness from 24 to 38 nm in diameter and a length of 410-2200 nm The largest member, the Thermoproteus - Tenax virus 1, is one of 38 × 2200 nm of the largest known virus species in the first. The Lipothrixviridae have complex, sometimes crescent-shaped protein structures at their ends. The genera of these filamentous ( filamentous ) viruses are distinguished already morphologically based on their flexibility or pliability: not flexible ( alpha ), inflexible ( beta ) or very flexible filaments ( gamma ). Between the typical representatives of the genus Alphalipothrixvirus (TTV -1) and the beta or Gammalipothrixviren exist surprisingly no matches or similarities in the genome sequence.

The genome within the family consists of a single DNA molecule with sizes from 15.9 to 56 kbp. The ends of the genome are extremely stable, which is caused by an as yet unknown chemical modification to degradation by exonucleases.

The hosts of the Lipothrixviridae are thermophilic bacteria and archaea (eg Thermoproteus tenax, Sulfolobus islandicus ). The AFV -1 of the extremely thermophilic archaea Acidianus hospitalis and Acidianus infernus, which are mainly found in volcanic hot springs and geysers. A certain relationship has the family Lipothrixviridae to Rudiviridae, but which have no shell. The representatives of both virus families have a similar genomic organization, filamentous capsid and infecting extremely thermophilic archaea of the Crenarchaeota department. Owing to the extended sequence analysis of a common evolutionary origin of the two families Rudiviridae and Lipothrixviridae can be assumed, which is why they are combined to form a new joint order Ligamenvirales since 2012.

System

• Family Lipothrixviridae

• Genus Alphalipothrixvirus

• Species - Thermoproteus tenax virus 1 (TTV -1)

• Genus Betalipothrixvirus

• Species Sulfolobus islandicus filamentous virus - ( SIFV )

• Species Desulfurolobus - ambivalens - filamentous virus ( DAFV )
• Species - Thermoproteus tenax virus 2 (TTV -2)
• Species - Thermoproteus tenax virus 3 (TTV -3)

• Genus Gammalipothrixvirus

• Species Acidianus filamentous virus - 1 ( AFV 1)

Not classified species within the family:

• Species Acidianus filamentous virus - 2 ( AFV -2)