Coralassociated

Coral-associated is a term used to describe organisms, symbionts, and processes that are linked to corals, especially within the coral holobiont. The coral holobiont is the integrated system comprising the coral animal, its photosynthetic dinoflagellate symbionts (Symbiodiniaceae), and a diverse microbial community that includes bacteria, archaea, fungi, and viruses. These associates can inhabit coral tissues, mucus, and skeleton or live in close, long-term relationships with the host.

The coral-associated microbiome is taxonomically diverse. Common bacterial groups include Endozoicomonas, Rhodobacteraceae, and Pseudovibrio; archaea contribute to nitrogen and carbon cycling; fungi and viruses also inhabit the system. The specific composition varies by coral species, geography, and environmental conditions. Together, these partners participate in nutrient cycling, defense against pathogens, and modulation of host metabolism and immunity, contributing to the health and resilience of the holobiont.

Ecologically, coral-associated communities are dynamic. Environmental stressors such as elevated sea temperatures, pollution, or acidification can alter microbial community structure, a process described as dysbiosis. Such shifts can influence susceptibility to disease and the likelihood of bleaching, though some microbial changes may aid recovery or acclimation.

Research approaches to coral-associated biology commonly use 16S rRNA gene sequencing and metagenomics to characterize bacterial and archaeal communities, ITS sequencing for fungi, and imaging methods like fluorescence in situ hybridization. The term emphasizes affiliation with corals and is used across microbiology, coral reef ecology, and conservation contexts to describe the intimate, functional relationships within the coral holobiont.