Hewson Lab at Cornell


Team Aquatic Virus - Microbial Oceanography, P.I. Ian Hewson, Ph.D.

Research by Team Aquatic Virus

The oceans cover 70% of the planet’s surface, and with an average depth of around 4 km, the marine environment is the largest biome on earth.  Marine bacteria and archaea, which maintain abundances of 105- 107 cells ml-1 surface seawater (roughly 80% of all C biomass), play crucial roles in global elemental cycles, consuming around half of all primary production, and causing net remineralization of organic into inorganic compounds. As the most abundant biological entities on earth (maintaining densitiesof 10^6-10^8 particles ml-1 seawater) marine viruses have significant impacts on their bacterial and archaeal hosts, causing significant mortality, controlling host assemblage structure, and conferring genomic capabilities via lysogenic conversion and gene transfer. Despite their global-scale importance, we are only starting to get a foothold on the diversity, distribution, and activities of microorganisms in the marine environment.

Research by Team Aquatic Virus at Cornell University combines biological oceanography with aquatic microbiology to elucidate the biogeochemical and ecological roles of viruses in the ocean. The lab’s work focuses on two aspects: Genomic and transcriptomic-enabled ecology and biogeochemistry of aquatic microorganisms. A large focus in the lab is viral ecology, but we also have active projects examining bacterial components of microbial assemblages. Below you will find a listing of active research projects in the lab:

Microbiology in Fayetteville Green Lake

  1. Allochthonous viruses of agricultural origin in New York State freshwater resources (USDA / NYS Hatch Grant)
  2. Characterization of thrombolitic bioherm cyanobacterial assemblages in a meromictic marl lake (Fayetteville Green Lake, New York)

Viruses of Daphnia

  1. Exploration of the presence and ecological significance of viral pathogens in the dynamics of Daphnia, a major pelagic grazer

Life in the Dead Zone

  1. Ian's trip to Maryland to conduct several experiments in the Dead Zone of the Chesapeake Bay

Metazoan Nanobiome Project

  1. Investigation into viruses of Elasmobranchs, including Squalus sp.
  2. Diversity of viruses associated with the echinoderm Asterias sp.
  3. Characterization of viral assemblages associated with the Gorgonia ventalina holobiont
  4. Viruses of the benthic amphipod Diporeia sp.

RNA viruses in sediments

  1. RNA viruses in the Water Column and Sediments of Babb’s Cove, Appledore Island, ME

Viruses of diazotrophic cyanobacteria

  1. Viruses associated with Diazotrophic Bacteria