UTA scientists investigate diseased Caribbean coral species

In new study, UTA biologists examine disease resistance of coral reefs in Caribbean

Tuesday, Jul 20, 2021 • Linsey Retcofsky : Contact

From left, Bradford Dimos, Laura Mydlarz and Nicholas MacKnight diving in Roatan, Honduras.
From left, Bradford Dimos, Laura Mydlarz and Nicholas MacKnight diving in Roatan, Honduras.

In a new study, biologists at The University of Texas at Arlington report that a coral reef’s tolerance for overall microbial imbalance when challenged with white plague disease reflects the coral’s overall disease resistance.

The new study, “Microbial dysbiosis reflects disease resistance in diverse coral species,” appears in the June 3, 2021, edition of the Nature online journal Communications Biology. The lead author was Nicholas MacKnight, a fourth-year doctoral student in the lab of Laura Mydlarz, professor of biology and associate dean of the College of Science. The research team worked in collaboration with colleagues at the University of the Virgin Islands in St. Thomas, V.I., the Nature Conservancy in Dallas, and Mote Marine Laboratory in Sarasota, Florida.

Coral species, which vary in their susceptibility to disease, have suffered severe declines due to disease outbreaks. The new research improves understanding of susceptibility among coral species that could help predict future disease impacts.

In coral communities, microbial dysbiosis is an unhealthy, disrupted state of imbalance in the holobiont, or the coral host and its associated microbiome. In this study, the researchers transmitted white plague disease to seven diverse Caribbean coral species in a controlled setting. White plague disease is one of the most destructive diseases in the Caribbean and has been devastating Caribbean coral species since the 1970s.

“Including these seven species is valuable because they represent diverse ecological contributions that define a coral reef,” MacKnight said. “The disease resistance was variable between the seven coral species, and this study provides insight into which coral species will survive the increased disease threats.”

The different species exhibited a spectrum of disease susceptibility and associated mortality that corresponded with their tolerances to microbial change, indicating that coral disease and microbial dysbiosis may ultimately shape reef ecosystems, the team noted.

“The increasing prevalence and severity of diseases affect coral species differently,” the team wrote in its new publication. “Because the functional contributions of these species define a reef, it is integral to understand variability in disease susceptibility among coral species to predict how the disease will shape coral reefs of the future.”

The paper’s co-authors include:

  • Bradford Dimos, UTA doctoral student in biology;
  • Lauren Fuess, assistant professor of biology at Texas State University who earned a Ph.D. at UTA in 2018;
  • Contessa Ricci, a researcher at the University of North Texas Health Science Center who earned a Ph.D. at UTA in 2019; and
  • Caleb Butler, a doctoral student at Penn State University who earned a B.S. degree from UTA in 2020.

“This paper makes important contributions to our knowledge of how variations in coral immune response can affect coral communities,” Mydlarz said. “I’m proud that so many members of my lab took part in this research and are co-authors of the paper. This project is particularly noteworthy for Nicholas since it’s his first publication as lead author.”

Additional co-authors include Marilyn Brandt, Kathryn Cobleigh, Danielle Lasseigne, Andia Chaves-Fonnegra, and Jendahye Antoine, all from the University of the Virgin Islands; Alexandra Gutting of The Nature Conservancy; and Erinn Muller of Mote Marine Laboratory.

The study is based on research conducted through funding from the National Science Foundation’s Division of Ocean Sciences. Mydlarz is principal investigator for the two-year, $220,331 grant, which was awarded in 2017.

- Written by Greg Pederson, College of Science