Spatial and temporal investigation of the microbiome of the Caribbean octocoralErythropodium caribaeorum

Abstract

The octocoral Erythropodium caribaeorum is an important species in the Caribbean coral reef community and a source of the cytotoxic natural product desmethyleleutherobin. We utilized 16S small subunit rRNA gene amplicon pyrosequencing to characterize the microbiome of E. caribaeorum collected from Florida, USA and San Salvador, The Bahamas at multiple time points. This coral was found to have a very high microbial richness with an average Chao1 estimated richness of 1464 ± 707 operational taxonomic units and average Shannon diversity index of 4.26 ± 1.65. The taxonomic class Gammaproteobacteria was a dominant member in all samples and the genus Endozoicomonas accounted for an average of 37.7% ± 30.0% of the total sequence reads. One Endozoicomonas sp. was found to be a stable member of all E. caribaeorum sequence libraries regardless of location or time of collection and accounted for 30.1% of all sequence reads. This is the first report characterizing the microbiome associated with the encrusting octocoral E. caribaeorum.

Geographical variations in bacterial communities associated with soft coral Scleronephthya gracillimum

“…Microbial composition of soft corals has been considered stable, with Endozoicomonas being the dominant genus of bacteria in most healthy soft Octocorallia corals, e.g. gorgonians [ 7 – 10 , 12 ] and Sarcophyton [ 42 ]. However, in the present study, bacterial composition of S .…”

“…Most studies of coral-associated bacteria have focused on reef building corals (Scleractinia), with relatively few studies of the microbiomes of octocorals, and those focussed on members of the Alcyonacea [ 7 – 12 ]. Among studies of Alcyonacea-associated microbiomes, the bacterial genus Endozoicomonas (Gammaproteobacteria) has been reported to be the dominant bacterial group in various host species [ 7 – 12 ]. It is noteworthy there have been reports of other bacteria being present in these microbiomes, including members of the genera Vibrionaceae, Tenericute, and Alphaproteobacteria [ 13 – 14 ].…”

Microbial Associations of Four Species of Algal Symbiont-bearing Foraminifers from the Florida Reef Tract, Usa

“…Advances in technology, such as next generation sequencing, are now allowing the analysis of the composition of marine-invertebrate microbiomes (McCauley et al, 2016). These culture-free, DNA-based techniques are especially important to the study of microbiomes of marine organisms because <1% of marine bacteria can be cultured using traditional methods (Rosenberg et al, 2007).…”

“…Research into microbiomes in marine invertebrates, mainly focusing on corals, has found that many species maintain a "core microbiome" that is distinct from the microbial composition of their surroundings (Rosenberg et al, 2007;McCauley et al, 2016). This means that, even though coral microbiomes are taxonomically diverse and can vary with location or environmental conditions, different species have a specific set of microbial taxa, or "core microbiome", with which they are consistently associated (Rosenberg et al, 2007;McCauley et al, 2016). The factors that control the composition of an organism's microbiome are still being explored, but studies of corals and sponges have revealed evidence for microbiome speciesspecificity.…”

“…The patterns of host specificity observed in this study agree with conclusions made in studies of coral microbiomes. In corals, the host is recognized as one of the strongest drivers of core microbiome composition, even considering temporal and geographic variation (Littman et al, 2009;La Rivière et al, 2015;Chu & Vollmer, 2016;McCauley et al, 2016). Studies comparing different species of corals found the microbial community to be more similar amongst closely related coral species (Sunagawa et al, 2010;La Rivière et al, 2015).…”