Marine Viral Ecology Laboratories

at the University of Hawaiʻi at Mānoa

We are a collective of two lab groups in the Department of Oceanography that collaborate to understand the diversity and ecological consequences of viral infections of marine plankton using theoretical and empirical approaches.

MarVEL Team Members

Kyle Edwards

Associate Professor

Grieg Steward

Professor

Julie Thomy

Post-doctoral Researcher

Anamica Bedi de Silva

Graduate Student

Andrian Gajigan

Graduate Student

Petra Byl

Graduate Student

Kelsey McBeain

Research Staff

Amanda Laughlin

Graduate Student

Learn more about our virus work and our other research interests at our individual lab group pages:

Theoretical and experimental plankton ecology - mathematical approaches to ecological systems

Viruses of phytoplankton, bacteria, & archaea - ecology, diversity, biogeochemical consequences

What are viruses?

Viruses are mobile genetic elements that differ from other such elements in having an extracellular form known as a virion. In the simplest form, a virion consists of the viral nucleic acid (the viral genome) packaged in a protein shell (capsid), but some types of viruses produce more complex virions with lipid membranes or protein appendages. No matter how complex, virions are not metabolically active and are not capable of growth or division, they are primarily vessels for delivery of  the virus' nucleic acid—and sometimes some enzymes— to the interior of a cell. If the viral genome enters the appropriate type of cell (a host), the cell's metabolic machinery, along with any machinery provided by the virus, will act on the information encoded in the genome to either replicate the viral genome as a genetic element within the cell or facilitate the assembly of new virions that exit the cell (usually killing the cell in the process). The first viruses likely arose together with the very first cells billions of years ago and have been co-evolving and diversifying with cells ever since. Others viruses likely had more recent, independent origins. The long history and multiple origins of viruses makes this an extraordinarily diverse suite of elements linked by a common general mode of replication. 

Why study marine viral ecology?

Every organism on our planet, from the largest whale to the tiniest bacterium, has evolved under the influence of, and remains susceptible to, infection by viruses. Viruses are perhaps best classified as molecular symbionts of cells with relationships that range from mutualistic to parasitic. As a mutualism, a virus' genome is stably replicated and maintained within the  cell and, in return, the expression of select viral genes provides the host cell with some benefit. In this mode, a virus alters the phenotype, and thus the ecological function, of the host cell. These mutually beneficial interactions are likely common among viruses and plankton in the ocean, but examples and mechanisms remain poorly documented. Better studied and understood are the examples of parasitism, in which a virus replicates within a cell, creating new virions at the expense of cell fitness. Most often the cell is lysed to release the newly assembled virions in the manner of a parasitoid. Viruses are one of the major contributors to plankton death in the ocean and, as a consequence, seawater is teeming with virions, often numbering in the tens of billions per liter. Because infections spread most readily through dense populations, and because viruses are specific in which types of cells they infect, infections are thought to disproportionately kill members of dominant populations. This equalizing effect from antagonistic virus-host interactions can promote diversity in marine microbial communities and drive succession of dominant populations. In habitats with persistently high or persistently low cell concentrations, selection may instead favor stable mutualistic relationships between viruses and their hosts. The many profound and complex interactions between viruses and their hosts and the extraordinary breadth of viral diversity that remains to be discovered make this one of the most exciting and challenging research areas in the marine sciences.

Recent Virus-related Publications

(visit our individual lab sites for full list of publications on all topics)