Microbial Interactions on Coral Surfaces and Within the Coral Holobiont

Abstract

Microbial communities associated with coral surfaces are diverse and complex. They play key roles in nutrient acquisition by coral holobionts and in responses to stressors and diseases. Members of coral-associated microbiota produce antimicrobial compounds, inhibit cell-to-cell signaling, and disrupt virulence in opportunistic pathogens. Characterization of coral-associated microbial communities suggests that metabolic capabilities define the core members of the communities. However, some taxonomic conservation is becoming evident in microbial communities associated with the same coral species and genera in different geographic regions. Even though shifts in the composition of coral microbiota often correlate with the appearance of signs of diseases and/or bleaching, it is not yet clear to what extent these shifts are a cause or a consequence of diseases. This chapter focuses on interactions within coral-associated microbial communities and suggests potentially interesting directions for future research.