The virus family guttaviridae with their original single genus Guttavirus were created as a new Bakteriophagenspezies in investigating extra-chromosomal genetic material in different strains of Archaeengattung Sulfolobus ( crenarchaeota ) was isolated and characterized. In a strain (Sulfolobus STH3 / 1, Sulfolobus neozealandicus ) of these extremely thermophilic and acidophilic archaebacteria, which came from a fumarole field south of Lake Taupo ( New Zealand ), viruses with a teardrop shape ( Latin gutta , `` drop '' ) were observed. The new virus species was named Sulfolobus neozealandicus drop-shaped virus (SNDV). In the meantime (as of November 2018) the ICTV has split this genus into two genera Alphaguttavirus (only species: SNDV) and Betaguttavirus (only species Aeropyrum pernix ovoid virus 1 , APOV1).
The virions (virus particles) Guttaviridae are enveloped , irregular, predominantly ovoid (egg or drop-shaped) shaped capsids . These white (at least) with the SNDV several thin filaments at their pointed end. The function of these filaments is unknown. The symmetry of the capsid is also unclear; stacked, helical structures appear under the electron microscope . The virions are 110 to 185 nm long and a maximum of 70 to 95 nm wide. One main structural protein (17.5 kDa ) and two smaller structural proteins (13.5 and 13 kDa) are detectable in the virion.
Genome
The genome of the SNDV consists of a circular, closed, double-stranded DNA ( cccDNA ) and is about 20 kBp long. The genome is also methylated in many places . Due to the special N (6) -methylation that does not occur in the host, it is assumed that the SNDV has its own DNA methyltransferase . The viral DNA cannot therefore be cleaved with most restriction endonucleases ; only the dam methylation-dependent restriction enzyme DpnI is able to cut SNDV DNA.
Systematics
Family Guttaviridae
Genus Alphaguttavirus
Species Sulfolobus newzealandicus droplet-shaped virus (SNDV)
Genus Betaguttavirus
Species Aeropyrum pernix ovoid virus 1 (APOV1)
swell
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HP Arnold et al. : SNDV, a novel virus of the extremely thermophilic and acidophilic archaeon Sulfolobus . Virology (2000) 272 (2): pp. 409-416, PMID 10873785 ( full text )
G. Lipps: Plasmids and viruses of the thermoacidophilic crenarchaeote Sulfolobus . Extremophiles (2006) 10 (1): pp. 17-28, PMID 16397749
