Integrated ‘omics uncovers phage-host dynamics in the ETNP Oxygen Minimum Zone

Viruses are the most abundant biological entities in seawater, yet their complex relationship with hosts, ecosystems and biogeochemistry make them one of the least understood components of the marine realm. Marine oxygen minimum zones (OMZs) are naturally occurring oxygen-depleted areas of the ocean. Increasing ocean temperatures due to global climate change are leading to a net loss of oceanic dissolved oxygen and intensifying stratification, consequently expanding their size and severity. Microbial processes carried out within OMZs contribute to global cycling of nitrogen, sulfur and carbon. Previous work suggests that viruses impact microbe-driven cycling of nutrients within OMZs, but the extent of this impact is unknown. Additionally, links between OMZ phages and their hosts remain unexplored. Using several interaction-based approaches for pairing phages and hosts, namely metaHi-C, single cell genomics and CRISPR spacer matching, we identify novel phage-host pairs from the oxic-anoxic transition zone, and the anoxic core of the Eastern North Tropical Pacific OMZ. With these pairs in hand, we layer additional ‘omics data to better understand the intracellular activity and abundance of phages relative to hosts across OMZ biogeochemical gradients. These profiles reveal differences in putative phage infection strategy across phage-host pairs, shining light on the impacts of phage infection in these globally important systems.

Presentation Preference: Oral

Primary Presenter: Julia Brown, Bigelow Laboratory for Ocean Sciences (julia@bigelow.org)

Authors:

Julia Brown, Bigelow Laboratory for Ocean Sciences  (julia@bigelow.org)

Rayna Hamilton, Woods Hole Oceanographic Institute  (rayna.hamilton@whoi.edu)

Maria Pachiadaki, Woods Hole Oceanographic Institute  (mpachiadaki@whoi.edu)