The Ligamenvirales represent an order of viruses , the hosts of which are thermophilic bacteria and archaea of the Crenarchaeota department . The order arose from the combination of the virus families Lipothrixviridae and Rudiviridae , since a common evolutionary precursor can be assumed through extended sequence analyzes, although there are differences in the structure of the virions. The viruses of the Lipothrixviridae are surrounded by a virus envelope , the Rudiviridae are envelopeless . Both families, however, represent viruses with a linear, non-segmented double-stranded DNA as genome, their capsid each shows a helical symmetry and they have similarities with regard to the host spectrum and the replication strategies. Both families have (depending on the different genera) up to ten genes in common. The folding structure of the capsid proteins of both families forms an unusual four-fold helix.
The virions of the Ligamenvirales are filamentous and have hair-like structures at both ends, which are associated with the host specificity and entry into the host cell. The name of the order is derived from this morphology (Latin ligamen : band, fetter).
D. Prangishvili, M. Krupovic: A new proposed taxon for double-stranded DNA viruses, the order "Ligamenvirales". Arch. Virol. (2012) 157 (4): pp. 791-795, PMID 22270758
A. Goulet, S. Blangy et al .: Acidianus filamentous virus 1 coat proteins display a helical fold spanning the filamentous archaeal viruses lineage . PNAS (2009) 15; 106 (50): pp. 21155-60 PMID 19934032
