Choosing probiotics with the greatest potential against amphibian chytridiomycosis.

Candidate probiotic bacteria (or fungi) are isolated from populations of amphibians that are able to persist in the presence of B. dendrobatidis (Bd) [1]. To increase the chances of successful prophylactic biotherapy, candidate probiotics should be tested for at least three characteristics: (a) capacity to inhibit Bd growth as a pure isolate without specific competitive interactions to induce antifungal metabolites, (b) capacity to inhibit Bd at a temperature range consistent with host habitat, and (c) resistance to host skin immune defenses that would complicate probiotic establishment. Remedial biotherapy of already infected individuals should maintain antifungal capacity when grown in competition with Bd and withstand the sometimes lethal effects of Bd metabolites (Fig. S6 in File S1). Testing probiotic effect in vivo can be accomplished without resorting to pathogen exposure experiments by using the mucosome function assay described here.