Microbial inhibitors of the fungus Pseudogymnoascus destructans, the causal agent of white-nose syndrome in bats

Abstract

Pseudogymnoascus destructans, the fungus that causes white-nose syndrome in hibernating bats, has spread across eastern North America over the past decade and decimated bat populations. The saprotrophic growth of P. destructans may help to perpetuate the white-nose syndrome epidemic, and recent model predictions suggest that sufficiently reducing the environmental growth of P. destructans could help mitigate or prevent white-nose syndrome-associated bat colony collapse. In this study, we screened 301 microbes from diverse environmental samples for their ability to inhibit the growth of P. destructans. We identified 145 antagonistic isolates, 53 of which completely or nearly completely inhibited the growth of P. destructans in co-culture. Further analysis of our best antagonists indicated that these microbes have different modes of action and may have some specificity in inhibiting P. destructans. The results suggest that naturally-occurring microbes and/or their metabolites may be considered further as candidates to ameliorate bat colony collapse due to P. destructans.

Restoration of Legacy Trees as Roosting Habitat for Myotis Bats in Eastern North American Forests

“…Concerted efforts are underway to develop blight resistant chestnut trees and restore this tree as a canopy dominant in eastern North American forests through genetic engineering, inter-and intra-specific breeding programs, and use of biocontrol with hypovirulence [80]. In turn, recent advances in the study of the Pseudogymnoascus fungus responsible for WNS have identified potential control strategies to reduce impacts to hibernating bats including use of ultraviolet light and microbial inhibitors [31,81]. Perhaps one day bark-and cavity-roosting bats in eastern North America will occupy American chestnut trees as roosting sites, but until then management efforts to increase availability of large-diameter trees via other canopy-dominant tree species could help facilitate reproduction and population recovery of bark-and cavity-roosting Myotis impacted by WNS.…”

“…The fungus causes structural damage to bat tissues, especially wings, with hyphae that penetrate hair follicles, apocrine glands, and sebaceous glands [28]. The fungus attacks bats while torpid, increasing the frequency of arousal and leading to energy loss, dehydration, emaciation, and immune responses to fungal infection that are lethal to the bats [29][30][31]. Collectively, these effects on hibernating bats have been termed white-nose syndrome (WNS), with recovery efforts of WNS-impacted Myotis now reliant on the ability of overwinter survivors to reproduce and successfully rear young bats to volancy during summer months [32].…”

Genome-wide changes in genetic diversity in a population ofMyotis lucifugusaffected by white-nose syndrome

“…Modelling also suggests that environmental factors, including the 407 20 cave microbiome, have an impact on the proliferation and infectivity of P. destructans 408 (Hayman, Pulliam, Marshall, Cryan, & Webb, 2016;Lilley et al, 2018). This is supported by 409 the discovery of microbes in hibernacula environments and bats that are able to retard the 410 growth of the fungus(Micalizzi et al, 2017; Zhang et al, 2014Zhang et al, , 2015. In light of our results 411 and considering bat life history as a whole, adaptation and evolutionary rescue may not be a 412 fast track for recovery of bat populations affected by WNS(Maslo and Fefferman, 2015).…”

Testing Natural Products for Toxicity against Agricultural Pests and Pathogens

“…The 10 fungal isolates chosen were previously described as producing anti-fungal metabolites at 13 °C (Micalizzi et al, 2017), thus we further hypothesized the use of all three bioassays would give insights on the presence of target-specific or general toxins.…”

“…Table 1 summarizes the 10 isolates used in this study along with describing the type of isolate, site of collection, and isolate ID. These fungal isolates were obtained in a previous study in a screen for microbes that inhibit Pseudogymnoascus destructans, a fungal pathogen of bats (Micalizzi et al, 2017). These isolates were stored on agar slants of Potato Dextrose Agar (PDA; Difco TM Laboratories Limited) at 13°C in the dark.…”