Predicting Microbiome Function Across Space Is Confounded by Strain-Level Differences and Functional Redundancy...

Area of Science:

• Ecology
• Microbiology
• Amphibian Biology

Background:

• Microbiome variation influences host susceptibility to disease.
• Predicting microbiome function is challenging due to spatial and temporal diversity.
• Amphibian die-offs linked to Batrachochytrium dendrobatidis (Bd) highlight the need to understand host-microbe interactions.

Purpose of the Study:

• To investigate how land use change affects the cutaneous bacterial communities of Plethodon cinereus.
• To determine if changes in skin microbiome composition correlate with altered Bd-inhibitory function.
• To assess the functional redundancy of Bd-inhibiting traits within amphibian microbiomes.

Main Methods:

• Isolation and sequencing of cutaneous bacterial communities from Plethodon cinereus.
• Assaying bacterial communities along a land use change gradient.
• Evaluating Bd-inhibitory function of the identified bacteria.

Main Results:

• Cutaneous bacterial community composition, but not diversity, varied with land use.
• No significant change in Bd-inhibitory function was observed despite shifts in community composition.
• Bd-inhibition was identified as a functionally redundant trait, with inhibition levels varying across phylogenetic, spatial, and temporal scales.

Conclusions:

• Land use impacts amphibian skin microbiome composition, but functional traits like Bd-inhibition may be resilient.
• Functional redundancy in the amphibian microbiome is critical for maintaining disease resistance.
• Further research on amphibian microbial communities across environmental gradients is essential for understanding disease dynamics.