1. The Influence Of Epidermal Fatty Acids On The Growth Of Pseudogymnoascus Destructans: The Fungus That Causes White-Nose Syndrome
- Abstract
White-nose Syndrome (WNS), a disease causing over-winter mortality of hibernating bats, is caused by the psychrophilic fungus Pseudogymnoascus destructans (Pd) which was introduced to upstate New York in 2006. Cutaneous epidermal infection with Pd results in erosions and lesions in the epidermal wing tissue, which causes a decrease in torpor bouts typical of WNS. The little brown bat (Myotis lucifugus) is susceptible to Pd infection however the big brown bat (Eptesicus fuscus) has not shown increased WNS mortality despite equal exposure to Pd. As the epidermis is the site of infection epidermal analysis between the species is warranted. The mammalian epidermis contains free fatty acids (FFA), some of which have been shown to have antifungal properties as part of the innate mammalian immune system. Analysis of E. fuscus and M. lucifugus epidermal FFA, as well as pre- and late hibernation FFA analysis in M. lucifugus was performed. E. fuscus epidermis contains significantly greater levels of myristic acid and oleic acid and decreased levels of pentadecanoic and stearic acid levels compared to M. lucifugus. Pre- and late hibernation comparisons in M. lucifugus revealed significant differences in all FFA except palmitic acid. Laboratory propagation of Pd on different FFA media found that increased levels of unsaturated FFA, linoleic and oleic acid, inhibited Pd growth compared to saturated FFA. Pd colonies grown on media simulating FFA content of E. fuscus were significantly smaller than those grown on media resembling M. lucifugus. These results suggest the FFA content of bat epidermis could be useful in identifying which hibernating species may be more susceptible to Pd infection which will become important as Pd spreads throughout both Canada and the United States.
- Published
- 2015