Gut and fecal microbiome profiles of the electric eel (Electrophorus varii) revealed by 16S rRNA amplicon sequencing

We report a 16S rRNA gene amplicon sequencing dataset describing gut and fecal microbiota of the electric eel <i>Electrophorus varii</i>, a freshwater electrogenic fish lacking baseline microbiome references. Fecal and gut samples (<i>n</i> = 3 per group) from an individual eel were analyzed to characterize genus-level taxonomic composition and alpha diversity. The gut samples were strongly predominated by <i>Cetobacterium</i>, whereas the fecal samples contained more heterogeneous community structures. Principal component analysis (PCA) based on Hellinger-transformed relative abundances was applied to primarily separate gut and fecal microbiota samples along the first principal component (PC1) axis (92.8 %). Shannon alpha diversity was significantly higher in fecal microbiota compared with gut microbiota. Although the present dataset is based on triplicate samples from a single individual, expanded studies incorporating multiple electrogenic species and species-level comparisons will be necessary to determine whether electric discharge environments are associated with significant shifts in freshwater fish gut microbiome structure.