Four newly isolated fuselloviruses from extreme geothermal environments reveal unusual morphologies and a possible interviral recombination mechanism.
Spindle-shaped virus-like particles are abundant in extreme geothermal environments, from which five spindle-shaped viral species have been isolated to date. They infect members of the hyperthermophilic archaeal genus Sulfolobus, and constitute the Fuselloviridae, a family of double-stranded DNA viruses. Here we present four new members of this family, all from terrestrial acidic hot springs. Two of the new viruses exhibit a novel morphotype for their proposed attachment structures, and specific features of their genome sequences strongly suggest the identity of the host-attachment protein. All fuselloviral genomes are highly conserved at the nucleotide level, although the regions of conservation differ between virus-pairs, consistent with a high frequency of homologous recombination having occurred between them. We propose a fuselloviral specific mechanism for interviral recombination, and show that the spacers of the Sulfolobus CRISPR antiviral system are not biased to the highly similar regions of the fusellovirus genomes.
Redder
Peter
P
Unite de Biologie Moleculaire du Gene chez les Extremophiles, Institut Pasteur, 25, rue du Dr Roux, F-75015 Paris, France. peterredder@gmail.com
Peng
Xu
X
Brügger
Kim
K
Shah
Shiraz A
SA
Roesch
Ferdinand
F
Greve
Bo
B
She
Qunxin
Q
Schleper
Christa
C
Forterre
Patrick
P
Garrett
Roger A
RA
Prangishvili
David
D
D017124:Conserved Sequence; D004279:DNA, Viral / Q000737:chemistry / Q000235:genetics; D019241:Fuselloviridae / Q000235:genetics* / Q000302:isolation & purification / Q000648:ultrastructure*; D023061:Gene Order; D045482:Hot Springs / Q000821:virology*; D046529:Microscopy, Electron, Transmission; D008969:Molecular Sequence Data; D011995:Recombination, Genetic; D017422:Sequence Analysis, DNA; D016944:Sulfolobus / Q000821:virology; D015678:Viral Structural Proteins / Q000648:ultrastructure; D014771:Virion / Q000648:ultrastructure*
D004279:DNA, Viral; D015678:Viral Structural Proteins