Wild dendrobatid frog microbiomes - bacteria

Shifts in microbiome community composition can have large effects on host
health. It is therefore important to understand how perturbations, like
those caused by the introduction of exogenous chemicals, modulate
microbiome community composition. In poison frogs within the family
Dendrobatidae, the skin microbiome is exposed to the alkaloids that the
frogs sequester from their diet and use for defense. Given the
demonstrated antimicrobial effects of these poison frog alkaloids, these
compounds may be structuring the skin microbial community. To test this,
we first characterized microbial communities from chemically defended and
closely related non-defended frogs from Ecuador. Then we conducted a
laboratory experiment to monitor the effect of the alkaloid
decahydroquinoline (DHQ) on the microbiome of a single frog species. In
both the field and lab experiments, we found that alkaloid-exposed
microbiomes are more species rich and phylogenetically diverse, with an
increase in rare taxa. To better understand the strain-specific behavior
in response to alkaloids, we cultured microbial strains from poison frog
skin and found the majority of strains exhibited either enhanced growth or
were not impacted by the addition of DHQ. Additionally, stable isotope
tracing coupled to nanoSIMS suggests that some of these strains are able
to metabolize DHQ. Taken together, these data suggest that poison frog
chemical defenses open new niches for skin-associated microbes with
specific adaptations, including the likely metabolism of alkaloids, that
enable their survival in this toxic environment. This work helps expand
our understanding of how exposure to exogenous compounds like alkaloids
can impact host microbiomes. Other data related to this manuscript can be
found in the following locations: https://doi.org/10.5061/dryad.5qfttdzd5,
Wild dendrobatid frog microbiomes -
bacteriahttps://doi.org/10.5061/dryad.gxd2547t1, Oophaga sylvatica
decahydroquinoline quantificationhttps://doi.org/10.5061/dryad.9ghx3ffqn,
Ecuadorian Dendrobatid frog alkaloid
profileshttps://doi.org/10.5061/dryad.tdz08kq62, Feeding experiment
microbiome - bacteriahttps://doi.org/10.5061/dryad.4mw6m90hn, Feeding
experiment microbiome - fungihttps://doi.org/10.5061/dryad.2ngf1vhzc,
Poison frog microbiome metagenomics
datahttps://doi.org/10.5061/dryad.9cnp5hqrm, Wild dendrobatid microbiomes
– fungi