Surgeonfish gut microbiota Metagenome

Abstract

Acanthuridae is an abundant family of coral reef fishes with a high diversity and wide range of feeding behaviors that influence the ecology of reefs. While previous studies have predominantly analyzed their social and ecological aspects, less is known about their gut microbiota. This strongly contrasts with higher vertebrates (especially ruminants and humans) or arthropods (e.g. termites and bees), where the compositions and functions of the gut microbiota have been extensively studied. A recent analysis of a wide variety of unrelated fish species indicated that salinity, trophic level, and possibly host phylogeny all shape the composition of the gut microbiota. However, it is currently unknown whether the microbiota of closely related fishes occupying the same habitat differ, and, if yes, what factors influence these differences. Here, we investigated the composition of the gut microbiota of nine surgeonfish and three non-surgeonfish species from the Red Sea. Overall, we found that the gut microbiota of all surgeonfishes were predominated by members of the phylum Firmicutes, especially members of the genus Epulopiscium. However, large inter- and intra-specific differences in the diversity of the gut microbiota were present, indicating the transient nature of most of the microbial gut populations. The similarities between gut microbiota of different fish species were independent of host phylogeny, but were strongly correlated with the host feeding behavior. This study is the first comprehensive study on the gut microbiota of a family of coral fishes from the same habitat, which highlights diet-related effects on the composition of the intestinal microbiome.