New archaeal viruses discovered by metagenomic analysis of viral communities in enrichment cultures |
| |
Authors: | Ying Liu David Brandt Sonoko Ishino Yoshizumi Ishino Eugene V Koonin Jörn Kalinowski Mart Krupovic David Prangishvili |
| |
Institution: | 1. Department of Bioscience and Biotechnology, Graduate School of Bioresource and Bioenvironmental Sciences, Kyushu University, Fukuoka, Fukuoka 819-0395, Japan;2. National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health, Bethesda, MD, 20892 USA;3. Center for Biotechnology, Universität Bielefeld, Bielefeld, 33615 Germany;4. Department of Microbiology, BMGE, Institut Pasteur, Paris, 75015 France |
| |
Abstract: | Viruses infecting hyperthermophilic archaea of the phylum Crenarchaeota display enormous morphological and genetic diversity, and are classified into 12 families. Eight of these families include only one or two species, indicating sparse sampling of the crenarchaeal virus diversity. In an attempt to expand the crenarchaeal virome, we explored virus diversity in the acidic, hot spring Umi Jigoku in Beppu, Japan. Environmental samples were used to establish enrichment cultures under conditions favouring virus replication. The host diversity in the enrichment cultures was restricted to members of the order Sulfolobales. Metagenomic sequencing of the viral communities yielded seven complete or near-complete double-stranded DNA virus genomes. Six of these genomes could be attributed to polyhedral and filamentous viruses that were observed by electron microscopy in the enrichment cultures. Two icosahedral viruses represented species in the family Portogloboviridae. Among the filamentous viruses, two were identified as new species in the families Rudiviridae and Lipothrixviridae, whereas two other formed a group seemingly distinct from the known virus genera. No particle morphotype could be unequivocally assigned to the seventh viral genome, which apparently represents a new virus type. Our results suggest that filamentous viruses are globally distributed and are prevalent virus types in extreme geothermal environments. |
| |
Keywords: | |
|
|