Identification and characterization of SNJ2, the first temperate pleolipovirus integrating into the genome of the SNJ1-lysogenic archaeal strain.
Proviral regions have been identified in the genomes of many haloarchaea, but only a few archaeal halophilic temperate viruses have been studied. Here, we report a new virus, SNJ2, originating from archaeal strain Natrinema sp. J7-1. We demonstrate that this temperate virus coexists with SNJ1 virus and is dependent on SNJ1 for efficient production. Here, we show that SNJ1 is an icosahedral membrane-containing virus, whereas SNJ2 is a pleomorphic one. Instead of producing progeny virions and forming plaques, SNJ2 integrates into the host tRNA(Met) gene. The virion contains a discontinuous, circular, double-stranded DNA genome of 16 992 bp, in which both nicks and single-stranded regions are present preceded by a 'GCCCA' motif. Among 25 putative SNJ2 open reading frames (ORFs), five of them form a cluster of conserved ORFs homologous to archaeal pleolipoviruses isolated from hypersaline environments. Two structural protein encoding genes in the conserved cluster were verified in SNJ2. Furthermore, SNJ2-like proviruses containing the conserved gene cluster were identified in the chromosomes of archaea belonging to 10 different genera. Comparison of SNJ2 and these proviruses suggests that they employ a similar integration strategy into a tRNA gene.
State Key Laboratory of Virology, College of Life Sciences, Wuhan University, Wuhan, 430072, China.
Ying
Y
Liu
State Key Laboratory of Virology, College of Life Sciences, Wuhan University, Wuhan, 430072, China.
Jiao
J
Wang
State Key Laboratory of Virology, College of Life Sciences, Wuhan University, Wuhan, 430072, China.
Yang
Y
Liu
State Key Laboratory of Virology, College of Life Sciences, Wuhan University, Wuhan, 430072, China.
Yuchen
Y
Wang
State Key Laboratory of Virology, College of Life Sciences, Wuhan University, Wuhan, 430072, China.
Ziqian
Z
Zhang
Institute of Biotechnology and Department of Biosciences, University of Helsinki, 00014, Helsinki, Finland.
Hanna M
HM
Oksanen
Institute of Biotechnology and Department of Biosciences, University of Helsinki, 00014, Helsinki, Finland.
Dennis H
DH
Bamford
State Key Laboratory of Virology, College of Life Sciences, Wuhan University, Wuhan, 430072, China.
Xiangdong
X
Chen
D000818:Animals; D023641:Archaeal Viruses / Q000145:classification / Q000235:genetics* / Q000302:isolation & purification* / Q000502:physiology; D020745:Genome, Archaeal; D006216:Halobacteriaceae / Q000821:virology*; D008242:Lysogeny; D005810:Multigene Family; D016366:Open Reading Frames; D011533:Proviruses / Q000235:genetics* / Q000648:ultrastructure; D012343:RNA, Transfer / Q000235:genetics; D014771:Virion / Q000235:genetics; D016662:Virus Integration
D012343:RNA, Transfer