The ocean is our planet’s life support system, regulating climate and sustaining an infinite variety of species, including our own. At the foundation of ocean food webs are algal blooms: vast colonies of microscopic algae that harness sunlight and are responsible for nearly half the oxygen generated through photosynthesis.
Algal blooms play a key role in stabilizing our climate, absorbing some 50 billion tons of atmospheric carbon annually and preventing the buildup of the heat-trapping greenhouse gases associated with climate change. Algal blooms can span thousands of miles across the ocean surface— some are visible from space—and can grow 50 meters deep. Despite their size, they are vulnerable to viruses that can infect a bloom and cause it to collapse and disappear within days.
Now, Prof. Assaf Vardi and postdoctoral fellow Dr. Constanze Kuhlisch of the Department of Plant and Environmental Sciences have identified 19 previously-unrecognized metabolites—chemical compounds that emerge during infection driven algal bloom collapse and reveal how viral infection unfolds over time.
The scientists also showed how viral infection causes algal cells to rupture, releasing their contents as dissolved organic matter, thereby redirecting energy and nutrients back to microbes and affecting carbon cycling in the ocean. Investigating blooms in four regions of the Atlantic Ocean, the team used varying levels of the metabolites they discovered to map each bloom’s distinct chemical “footprint,” thereby characterizing the course of infection.
A more comprehensive understanding of how collapsing algal blooms “misdirect” their chemical contents into the ocean and away from food production is essential to grasp the impact viral infections have on the fate of carbon in marine ecosystems and the atmosphere. The findings achieved by Prof. Vardi and Dr. Kuhlisch, published in the prominent journal Proceedings of the National Academy of Sciences, may help establish a new metric for modeling how viral infection affects the marine carbon cycle, and how this dynamic contributes to climate change.
ASSAF VARDI IS SUPPORTED BY:
- The de Botton Center for Marine Science
- Scott Eric Jordan
- The Tom and Sondra Rykoff Fund for Plant, Environmental, and Sustainability Research
- The Bronfman Professorial Chair of Plant Science
- The Beck Research Fellow Chair supports a staff scientist in Prof. Vardi’s lab
Algal blooms play a key role in stabilizing our climate, absorbing some 50 billion tons of atmospheric carbon annually and preventing the buildup of the heat-trapping greenhouse gases associated with climate change.
