Changes in the community structure of the symbiotic microbes of wild amphibians from the eastern edge of the Tibetan Plateau

Abstract

Environment has a potential effect on the animal symbiotic microbiome. Here, to study the potential relationship of the symbiotic microbiomes of wild amphibians with altitude, we collected the gut and skin samples from frogs (nine species) and the environmental samples (water and soil samples) from the Leshan Mountains (altitude: 360–410 m) and Gongga Mountains (altitude: 3340–3989 m) on the eastern edge of the Tibetan Plateau. Bufo gargarizans (Bg) samples were collected from both the Leshan and Gongga mountain regions (Bg was the only species sampled on both mountains). The DNA extracted from each sample was performed high‐throughput sequencing (MiSeq) of bacterial 16S rRNA gene amplicons. High relative abundance of Caulobacteraceae and Sphingomonadaceae was found in skin samples from both Bg and the other high‐altitude amphibians (nine species combined). High relative abundance of Coxiellaceae and Mycoplasmataceae was found in gut samples from both Bg and the other high‐altitude amphibians. Furthermore, the alpha and beta diversities of skin and gut samples from Bg and the other amphibian species (nine species combined) were similar. In terms of the symbiotic microbial community, the low‐altitude samples were less diverse and more similar to each other than the high‐altitude samples were. We speculated that extreme high‐altitude environments and host phylogeny may affect the amphibian microbiome. Despite the distinct microbial community differences between the skin and gut microbiomes, some functions were similar in the Bg and combined high‐altitude samples. The Bg and high‐altitude skin samples had higher oxidative stress tolerance and biofilm formation than the low‐altitude skin samples. However, the opposite results were observed for the Bg and high‐altitude gut samples. Further study is required to determine whether these characteristics favor high‐altitude amphibian adaptation to extreme environments.

The Behavior of Amphibians Shapes Their Symbiotic Microbiomes

“…Symbiotic microbiome communities vary across the body (31). Our previous studies revealed the differences in the skin, stomach, and gut microbiomes in amphibians (32,33). Here, significant differences in the symbiotic microbiome communities on the skin and in the stomach and gut within each species (occupying site factor) were observed.…”

Skin microbiome correlates with bioclimate and Batrachochytrium dendrobatidis infection intensity in Brazil’s Atlantic Forest treefrogs

“…Both measures of alpha diversity were reduced at high elevations. Xu et al 106 could also demonstrate a decrease in skin bacterial richness in wild amphibians from the Tibetan Plateau with increasing elevation. However, Medina et al 24 found no effect of elevation on neither bacterial richness nor evenness in Silverstoneia flotator .…”

Hypoxia: The “Invisible Pusher” of Gut Microbiota

“…SCFA levels in Yak rumens are higher than those in cattle, thus helping them adapt to high altitudes ( Zhang et al, 2016 ). Other animals, such as black-necked cranes ( Grus nigricollis ) ( Wang et al, 2020 ), lizards ( Phrynocephalus vlangalii ) ( Zhang W. et al, 2018 ), Chinese Rhesus macaques ( Macaca mulatta ) ( Zhao et al, 2018 ; Wu et al, 2020b ), Bufo gargarizans ( Xu et al, 2020 ), Tibetan chickens ( Zhou et al, 2016 ) and Tibetan pigs ( Zeng et al, 2020 ), also have high abundances of Ruminococcus in their guts ( Table 1 ). These data indicate the importance of Ruminococcus in plateau adaptation and hypoxia-tolerant animals.…”