PROKARYOTIC-VIRUS-ENCODED AUXILIARY METABOLIC GENES THROUGHOUT THE GLOBAL OCEANS

Viruses impact biogeochemical cycles, through lysis, horizontal gene transfer, and encoding and expressing genes that contribute to metabolic reprogramming of prokaryotic cells. While this impact is difficult to quantify in nature, we hypothesized that it can be examined qualitatively by surveying virus-encoded auxiliary metabolic genes (AMGs) and assessing their ecological context. We systematically developed a global ocean AMG catalog by integrating previously described and newly identified AMGs, and then placed this catalog into ecological and metabolic contexts. From 7.6 terabases of Tara Oceans paired prokaryote- and virus-enriched metagenomic sequence data, we increased known ocean virus populations to 579,904 (up 16%). From these virus populations, we then conservatively identified 86,913 AMGs that grouped into 22,779 sequence-based gene clusters, 7,248 (~32%) of which were not previously reported. Using our catalog and modeled data from mock communities, we estimate that ~19% of ocean virus populations carry at least one AMG. To understand AMGs in their metabolic context, we identified 340 metabolic pathways encoded by ocean microbes, and showed that AMGs map to 128 of them. Furthermore, we identified metabolic ‘hot spots’ targeted by virus AMGs, including nine pathways where most steps (≥0.75) were AMG-targeted. Together, this systematically curated, global ocean AMG catalog and analyses provides a valuable resource and foundational observations to understand the role of viruses in modulating global ocean metabolisms and their biogeochemical implications.  

Presentation Preference: Oral

Primary Presenter: James Wainaina, Woods Hole Oceanographic Institution (jwmbora@gmail.com)

Authors:

James Wainaina, Woods Hole Oceanographic Institution  (james.wainaina@whoi.edu)

James Wainaina, Department of Medicine, University of Chicago  (james.wainaina@whoi.edu)

Cristina Howard-Varona, Ohio State University  (howard-varona.2@osu.edu)

Guillermo Domínguez-Huerta, Centro Oceanográfico de Málaga (IEO-CSIC)  (guillermo.dominguez@ieo.csic.es)

Benjamin Bolduc, Ohio State University  (bolduc.10@osu.edu)

Consuelo Gazitúa, Viromica Consulting, Santiago  (consuelogazitua@gmail.com)

Garrett Smith, Ohio State University  (smith.10284@osu.edu)

Marissa Gittrich, Ohio State University  (gittrich.1@buckeyemail.osu.edu)

Olivier Zablocki, Ohio State University  (zablocki.4@osu.edu)

Dylan Cronin, Ohio State University  (cronin.87@buckeyemail.osu.edu)

James Wainaina, Université de Nantes  (james.wainaina@whoi.edu)

Steven Hallam, University of British Columbia  (shallam@mail.ubc.ca)

Matthew Sullivan, Ohio State University  (sullivan.948@osu.edu)