Evidence for host specificity among dominant bacterial symbionts in temperate gorgonian corals

摘要: Gorgonian corals serve as key engineering species within Mediterranean rocky-shore communities that have recently suffered from repeated mortality events during warm temperature anomalies. Among the factors may link thermal conditions with disease outbreaks, a number of bacterial pathogens been implicated; they take advantage decreases in defenses and/or overall health gorgonian hosts. Considering beneficial role resident bacteria tropical coral holobionts, detailed characterization gorgonian-associated microbial populations is required to better understand relationships among native microbiota, host fitness, and pathogen susceptibility. In this study, associated three sympatric species, Eunicella singularis, cavolini, Corallium rubrum, were investigated provide insight into stability specificity host–microbe interactions. Natural variations detected using terminal restriction fragment length polymorphism (T-RFLP) 16S ribosomal DNA. No major differences identified between individual colonies sampled winter or summer each species. Although hierarchical cluster analysis T-RFLP profiles revealed harbor distinct communities, comparison peaks indicated presence common ribotypes. From phylogenetic rDNA clone libraries, we lineage related Hahellaceae family Oceanospirillales shared E. C. rubrum dominates both Eunicella. However, clades are harbored by various waters, suggesting these formed host-specific symbiotic octocorals. addition, relatedness symbionts belonging same taxon but occurring geographically remote areas consistent codivergence gorgonians their bacteria.