Department of Biology

Excitement was in her voice as Victoria Lydick, who oversees the new coral facility at IU Bloomington, explained the purpose of the tanks and other equipment in the lab. Lydick is a research associate in the laboratory of Julia van Kessel, an associate professor in the IU College of Arts and Sciences Department of Biology.

The National Science Foundation and its internationally funded Binational Science Foundation have awarded a grant to van Kessel and colleagues to study the coral reef ecosystem. Specifically, the researchers hope to gain a better understanding of how to help maintain coral reefs by learning how the coral pathogen Vibrio coralliilyticus interacts with its environment in a coral host.

About half of the world’s total coral reef cover has been lost since the 1950s due to many causes—including anthropogenic climate change, disease outbreaks, destructive fishing practices, and pollution. Increases in ocean temperature due to climate change correlate with increased disease incidence and outbreaks in coral.

The bacterium V. coralliilyticus is a primary and opportunistic pathogen that infects numerous species of coral and causes bleaching and tissue loss, as well as potentially exacerbating the effects of other diseases.

The van Kessel lab—which specializes in quorum sensing, a cell-cell communication signaling process used by some bacteria—and colleagues hypothesize that quorum sensing signaling and temperature variations control virulence genes of V. coralliilyticus that are critical to the bacteria’s ability to infect coral. They will investigate how temperature, other bacteria, and communications between V. coralliilyticus populations alter the ability of the pathogens to cause coral diseases. The researchers will identify and examine virulence factors controlled by primary systems that respond to the environment as well as examine how each of these systems influences coral colonization and disease progression in a live coral infection model and its microbiome.

With guidance from Blake Ushijima, an assistant professor at University of North Carolina Wilmington, and his graduate students, Lydick continues to prepare the IU facility for the coral.

“We’ll be using the coral species Pocillopora damicornis for our research,” said Lydick. “This species is a branching coral which makes it important for reef structure in coastal reefs. It is an incredibly hardy coral species which makes it suitable for aquaculture experiments.”

The researchers are eager to share with the public how global warming specifically affects coral, their natural microbiomes, coral pathogens, and the animals that inhabit coral reefs. As their research evolves, they plan to showcase connections between bacterial pathogens and coral disease by using a live coral exhibit and live bacterial cultures in public outreach exhibits.

“In addition to corals, the Vibrio bacteria are pathogenic to fish, shellfish, and urchins; thus, discoveries from our work will contribute to a fundamental understanding of Vibrio pathogenesis and extend to other research programs,” said van Kessel. “Bacteria have intimate and influential interactions with the environment in many ways that are relevant to society. It is critical that we enable people in our communities to connect with science and observe basic research to understand how it impacts their daily lives.”

Collaborating with the van Kessel lab on the project are the Ushijima lab, University of North Carolina Wilmington, and the laboratory of Dor Salomon, Tel Aviv University.