16S rRNA sequences from Siganidae (S. rivulatus and S. luridus) gut microbiome in their native (Red Sea) and invaded (Mediterranean Sea) ranges (Q8512)

The microbiome of invasive species is increasingly seen as a potential key factor of their ecological success, and this appears particularly true in herbivorous invaders whose digestive abilities rely on the microbes hosted in their gut. We characterized the gut microbiome of two invasive herbivorous fishes (Siganus rivulatus and Siganus luridus) in their native (Red Sea) and invaded (Levantine Sea and Northern Crete) ranges. We found that gut bacterial communities contain a higher taxonomic and phylogenetic diversity while becoming increasingly different from the native microbiome as the fishes move away from the native zone. This shift resulted in the homogenization of the microbiomes between individuals from the same species as well as between the two species. Firmicutes and Tenericutes reduced drastically in abundance while Proteobacteria and Bacteroidetes became more dominant in both species. This led to a modification of the functional potential of the gut microbiome associated with the metabolism of short-chanin fatty acids that also became more homogeneous in the invaded range. Altogether, our results suggest that the plasticity of the gut microbiome in Siganidae could be a key factor underlying their ecological success in Mediterranean ecosystems.