Coral microbial ecology is the study of the relationship of coral-associated microorganisms to each other, the coral host, and to their environment. Just as we humans have beneficial bacteria living on our skin and in our intestines, corals also have co-habitating non-pathogenic (not disease-causing) microbes. These microbes include bacteria, archaea, and fungi—representing all three of the major domains of life.
What can we learn from studying coral microbial ecology? Why is it important? Coral reefs in the Caribbean have been in decline for several decades. One of the most visible causes is disease. Coral diseases are not well understood, but the few that have been characterized are all caused by microorganisms. In order to understand the diseased state, we must first understand the healthy state. Until now, coral biology studies have been limited to studies of the coral animal, the algal symbiont, or the interactions of the two. Coral microbial-ecology studies contribute a missing piece of information to the study of overall coral biology. It has been speculated that coral-associated bacteria benefit the coral by fixing nitrogen, breaking down waste products, and cycling basic nutrients back to the photosynthetic algal symbionts (zooxanthellae). Bacteria may also ward off other potentially harmful microbes by producing antibiotics or by just occupying the available space.
The coral microbial ecology group has an active research program identifying and characterizing the microbial associates of both tropical and cold-water (deep-sea) corals and their surrounding habitat. Current projects focus on coral disease dynamics, bacterial diversity, and using metagenomics to elucidate the functional roles of coral microbes.
