Creating synthetic microbiomes to understand ecological interactions involved in the snake fungal disease system.

An appreciation of microbiomes has changed the way we think about disease. Snake Fungal Disease (SFD), caused by the microbe, Ophidiomyces ophiodiicola (Oo), can be understood as an imbalance of the microbiotic community, facilitating an increased growth and dominance of Oo . As a community ecology problem, microbes can facilitate or inhibit Oo growth through ecological processes either directly or indirectly. Previous studies have shown interactions of microbes in synthetic systems mimicking the snake skin microbiome. We tested the indirect effects of microbes on the growth of Oo on petri plates, with minimal media, and keratin( the major component of snake skin) as the only carbon source. The minimal keratin media was inoculated with two bacterial members of the snakeskin microbiome isolates associated with the presence or absence of infection with Oo, Stenotrophomonas sp. and Chryseobacterium sp. and each allowed to grow for 24 hours, in minimal broth medias, with and without keratin. The media was vacuum filtered, so that only indirect effects of metabolizing the media would affect later growth. A subset of each media was then subjected to incubation with the opposite microbe to test for possible serial effects, as well as a simple additive treatment made by mixing the original two spent medias. These spent media were incorporated into minimal agar plates, inoculated with Oo, and Oo growth was monitored every two days for fourteen days. The fungus showed strong growth in keratin media compared to the minimal media. While there was strong growth of the bacteria in keratin media, single and additive treatments did not differ from un-inoculated keratin media. Serially inoculated keratin media, showed less growth, which might be explained a number of ways. One serial treatment caused a phenotypic change in the hyphal growth of Oo, and we will explore this further. [ABSTRACT FROM AUTHOR]