Welcome to the Sullivan Lab

Viruses Impact Microbial Processes – in the oceans, soils and humans


As the world faces global change and resource limitation, understanding the planet’s microbes (e.g. bacteria, archaea) becomes a necessity. This is because microbes drive the biogeochemistry that runs the planet, and are central to human endeavors, from food to health to industry. Viruses that infect microbes profoundly shape microbial populations and processes by acting as both major predators and sources of new genes.

We work to understand viral impacts on globally important microbial processes. As empiricists, we test hypotheses through direct systems-level studies of natural populations, complemented by developing and studying model phage-host systems in the lab with the goal of generating the data required for predictive ecosystem modeling. Practically, we develop new ways to “see” viruses — in the microscope, in environmental sequence datasets, in experiments — i.e., we are learning how to “count” across different data types.

Given this quantitative toolkit, current research questions include:
1) What is a viral population or species?
2) How do viral assemblages change over space and time, and what drives these patterns?
3) How do bottom-up processes impact top-down predators?

While our work has largely been “oceans” focused, we now also apply these approaches to viruses of microbes in soils and humans.


iVirusSo you have a viral metagenomic sequence, what next?


Find out more on our Informatics page. To meet the growing needs of the broader community of viral researchers, tools and important datasets need to co­exist in a common cyberinfrastructure. iVirus and iMicrobe were developed to support this need leveraging the CyVerse Cyberinfrastructure (iVirus paper here). These projects are led by and/or in collaboration with Bonnie Hurwitz, Assistant Professor, University of Arizona.

Trouble with iVirus? To date, apps often break with Cyverse updates. However, as of Jan 2017, apps should be more robust due to Ben Bolduc’s heroic efforts to convert everything to Singularity. Additionally, CyVerse does not handle documentation well, so all our iVirus documentation is available through protocols.io.  If you know Ben, please thank him for his hard (and often thankless) work keeping things running behind the scenes !



Science CoverTara Oceans Special Issue in Science


In a special issue of Science, five papers uncover new information about the ways in which marine viruses and microbes interact on a global scale. The work is part of the Tara Oceans Expedition, a global effort to understand complex interactions among ocean ecosystems, climate, and biodiversity.