Title |
Distinct gut microbiotas between southern elephant seals and Weddell seals of Antarctica |
Author |
Mincheol Kim, Hyunjun Cho, and Won Young Lee* |
Address |
Division of Polar Life Sciences, Korea Polar Research Institute, Incheon 21990, Republic of Korea |
Bibliography |
Journal of Microbiology, 58(12),1018–1026, 2020,
|
DOI |
10.1007/s12275-020-0524-3
|
Key Words |
gut microbiome, marine mammal, Phocidae, Antarctic
seal, NMR |
Abstract |
The gut microbiome provides ecological information about
host animals, but we still have limited knowledge of the gut
microbiome, particularly for animals inhabiting remote locations,
such as Antarctica. Here, we compared fecal microbiota
between southern elephant seals (Mirounga leonina)
and Weddell seals (Leptonychotes weddelli), that are top predatory
marine mammals in the Antarctic ecosystem, using 16S
rRNA amplicon sequencing and assessed the relationships
of the gut microbial communities to functional profiles using
gut metabolite analysis. The bacterial community did not
differ significantly by host species or sex at the phylum level,
but the distinction at the family level was obvious. The family
Ruminococcaceae (Firmicutes) was more abundant in southern
elephant seals than in Weddell seals, and the families
Acidaminococcaceae (Firmicutes) and Pasteurellaceae (Gammaproteobacteria)
were uniquely present in Weddell seals.
The fecal bacterial community structure was distinctively clustered
by host species, with only 6.7% of amplicon sequence
variants (ASVs) shared between host species. This result implies
that host phylogeny rather than other factors, such as
diet or age, could be the major driver of fecal microbiotic diversification.
Interestingly, there was no apparent sex effect
on bacterial community structure in Weddell seals, but the
effect of sex was pronounced in adult southern elephant seals
mainly due to the prevalence of Edwardsiella sp., suggesting
that extreme sexual dimorphism may modulate the gut microbiota
of southern elephant seals. Unlike the clear distinction
in the taxonomic composition of fecal bacterial communities,
there were no discernible differences in the profiles
of potential microbial functions and gut metabolites between
host species or sexes, indicating that functional redundancy
dominates the gut microbiota of seals surveyed in this study. |