Haloarchaeal virus morphotypes

摘要: Abstract Hypersaline waters and salt crystals are known to contain high numbers of haloarchaeal cells their viruses. Both culture-dependent culture-independent studies indicate that these viruses represent a world-wide distributed reservoir orphan genes possibly novel virion morphotypes. To date, 90 have been described for halophilic archaeal hosts, all belonging the Halobacteriaceae family. This number is higher than members any other family, but still very low compared bacteria eukaryotes. The icosahedral tailed, internal membrane-containing, pleomorphic, spindle-shaped morphotype distribution low, especially when astronomical (>10 31 ) on Earth. strongly suggests only certain protein folds capable making functional virion. Viruses infecting three domains life share similar major capsid which can be used classify into structure-based lineages. latest observation supporting this proposal comes from tailed most abundant virus isolates hypersaline environments. These were shown same fold (HK97-fold) with bacteriophages order Caudovirales eukaryotic herpes proposes common origin dating back ancient times. Here we summarize current knowledge perspective