Variation in the intestinal microbiota of tadpole and adult Hynobius
maoershanensis
Abstract
The intestinal microbiota play an important role in the life of
amphibians. The composition of the intestinal microbial community may
vary by developmental stage. In this study, 16S rRNA high-throughput
sequencing was used to study the intestinal microbiota of Hynobius
maoershanensis tadpoles and adults that exclusively inhabit the Maoer
Mountain swamp at an altitude of approximately 2000 m. The results
indicated that there was no significant difference in intestinal
microbiota between tadpoles and adults. Nevertheless, the abundance of
intestinal microbiota in adults was much higher than that in tadpoles.
Specifically, at the phylum level, Bacteroidetes was more abundant in
adults than in tadpoles. At the genus level, Proteobacteria,
Actinobacteria, Cyanobacteria, and Planctomycetes were more abundant in
tadpoles, whereas Burkholderiaceae, Caedibacter, Bacteroides, and
Serratia were more abundant in adults. A functional prediction analysis
revealed that there was no significant difference between tadpoles and
adults; however, the function of the intestinal microbiota in H.
maoershanensis includes amino acid transport and metabolism, general
function prediction only, transcription, energy production and
conversion, liquid transport, and metabolism. The aquatic and
terrestrial living environment of tadpoles and adults may be the main
reason for the difference in intestinal microbiota between tadpoles and
adults. Our study provides evidence of variations in the intestinal
microbiota of tadpoles and adult amphibians, highlighting the influence
of historical developments on the intestinal microbiota and the need for
increased understanding of the importance of physiological
characteristics in shaping intestinal microbiota of amphibians, which
consequently help us to understand the adaptative mechanism of
amphibians from an aquatic to a terrestrial environment.