Combining genomic sequencing methods to explore viral diversity and reveal potential virus-host interactions.
Viral diversity and virus-host interactions in oxygen-starved regions of the ocean, also known as oxygen minimum zones (OMZs), remain relatively unexplored. Microbial community metabolism in OMZs alters nutrient and energy flow through marine food webs, resulting in biological nitrogen loss and greenhouse gas production. Thus, viruses infecting OMZ microbes have the potential to modulate community metabolism with resulting feedback on ecosystem function. Here, we describe viral communities inhabiting oxic surface (10 m) and oxygen-starved basin (200 m) waters of Saanich Inlet, a seasonally anoxic fjord on the coast of Vancouver Island, British Columbia using viral metagenomics and complete viral fosmid sequencing on samples collected between April 2007 and April 2010. Of 6459 open reading frames (ORFs) predicted across all 34 viral fosmids, 77.6% (n = 5010) had no homology to reference viral genomes. These fosmids recruited a higher proportion of viral metagenomic sequences from Saanich Inlet than from nearby northeastern subarctic Pacific Ocean (Line P) waters, indicating differences in the viral communities between coastal and open ocean locations. While functional annotations of fosmid ORFs were limited, recruitment to NCBI's non-redundant "nr" database and publicly available single-cell genomes identified putative viruses infecting marine thaumarchaeal and SUP05 proteobacteria to provide potential host linkages with relevance to coupled biogeochemical cycling processes in OMZ waters. Taken together, these results highlight the power of coupled analyses of multiple sequence data types, such as viral metagenomic and fosmid sequence data with prokaryotic single cell genomes, to chart viral diversity, elucidate genomic and ecological contexts for previously unclassifiable viral sequences, and identify novel host interactions in natural and engineered ecosystems.
Department of Earth, Ocean, and Atmospheric Sciences, University of British Columbia Vancouver, BC, Canada.
Cheryl-Emiliane T
CE
Chow
Department of Earth, Ocean, and Atmospheric Sciences, University of British Columbia Vancouver, BC, Canada.
Danielle M
DM
Winget
Department of Microbiology and Immunology, University of British Columbia Vancouver, BC, Canada.
Richard A
RA
White
Department of Microbiology and Immunology, University of British Columbia Vancouver, BC, Canada ; Integrated Microbial Biodiversity Program, Canadian Institute for Advanced Research Toronto, ON, Canada ; Graduate Program in Bioinformatics, University of British Columbia Vancouver, BC, Canada.
Steven J
SJ
Hallam
Department of Earth, Ocean, and Atmospheric Sciences, University of British Columbia Vancouver, BC, Canada ; Department of Microbiology and Immunology, University of British Columbia Vancouver, BC, Canada ; Integrated Microbial Biodiversity Program, Canadian Institute for Advanced Research Toronto, ON, Canada ; Department of Botany, University of British Columbia Vancouver, BC, Canada.
Curtis A
CA
Suttle
fosmids; marine virus; metagenomics; microbial ecology; reference genome; single cell genomics; virome