Resurrection of a global, metagenomically defined Gokushovirus
- University of Texas at Austin, United States
Abstract
Gokushoviruses are single-stranded, circular DNA bacteriophages found in metagenomic datasets from diverse ecosystems worldwide, including human gut microbiomes. Despite their ubiquity and abundance, little is known about their biology or host range: Isolates are exceedingly rare, known only from three obligate intracellular bacterial genera. By synthesizing circularized phage genomes from prophages embedded in diverse enteric bacteria, we produced gokushoviruses in an experimentally tractable model system, allowing us to investigate their features and biology. We demonstrate that virions can reliably infect and lysogenize hosts by hijacking a conserved chromosome-dimer resolution system. Sequence motifs required for lysogeny are detectable in other metagenomically defined gokushoviruses; however, we show that even partial motifs enable phages to persist cytoplasmically without leading to collapse of their host culture. This ability to employ multiple, disparate survival strategies is likely key to the long-term persistence and global distribution of Gokushovirinae.
Data availability
The data used in this publication (accession numbers, sequences and alignments) are available in the manuscript, its supplementary files and on datadryad.org: https://doi.org/10.5061/dryad.z8w9ghx7s
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Resurrection of a Global, Metagenomically Defined GokushovirusDryad Digital Repository, doi.org/10.5061/dryad.z8w9ghx7s.
Article and author information
Author details
Paul C Kirchberger
Funding
National Institutes of Health (26-1612-1250)
- Howard Ochman
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2020, Kirchberger & Ochman
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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