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Lu Y, Ren H, Li Z, Leng H, Li A, Dai W, Huang L, Feng J, Sun K. Microbiota diversity and anti- Pseudogymnoascus destructans bacteria isolated from Myotis pilosus skin during late hibernation. Appl Environ Microbiol 2024; 90:e0069324. [PMID: 39058040 PMCID: PMC11337810 DOI: 10.1128/aem.00693-24] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2024] [Accepted: 07/04/2024] [Indexed: 07/28/2024] Open
Abstract
Symbiotic microorganisms that reside on the host skin serve as the primary defense against pathogens in vertebrates. Specifically, the skin microbiome of bats may play a crucial role in providing resistance against Pseudogymnoascus destructans (Pd), the pathogen causing white-nose syndrome. However, the epidermis symbiotic microbiome and its specific role in resisting Pd in highly resistant bats in Asia are still not well understood. In this study, we collected and characterized skin microbiota samples of 19 Myotis pilosus in China and explored the differences between Pd-positive and negative individuals. We identified inhibitory effects of these bacteria through cultivation methods. Our results revealed that the Simpson diversity index of the skin microbiota for positive individuals was significantly lower than that of negative individuals, and the relative abundance of Pseudomonas was significantly higher in positive bats. Regardless of whether individuals were positive or negative for Pd, the relative abundance of potentially antifungal genera in skin microbiota was high. Moreover, we successfully isolated 165 microbes from bat skin and 41 isolates from positive individuals able to inhibit Pd growth compared to only 12 isolates from negative individuals. A total of 10 genera of Pd-inhibiting bacteria were screened, among which the genera Algoriella, Glutamicibacter, and Psychrobacter were newly discovered as Pd-inhibiting genera. These Pd-inhibiting bacteria metabolized a variety of volatile compounds, including dimethyl trisulfide, dimethyl disulfide, propylene sulfide, 2-undecanone, and 2-nonanone, which were able to completely inhibit Pd growth at low concentrations.IMPORTANCERecently, white-nose syndrome has caused the deaths of millions of hibernating bats, even threatening some with regional extinction. Bats in China with high resistance to Pseudogymnoascus destructans can provide a powerful reference for studying the management of white-nose syndrome and understanding the bats against the pathogen's intrinsic mechanisms. This study sheds light on the crucial role of host symbiotic skin microorganisms in resistance to pathogenic fungi and highlights the potential for harnessing natural defense mechanisms for the prevention and treatment of white-nose syndrome. In addition, this may also provide promising candidates for the development of bioinsecticides and fungicides that offer new avenues for addressing fungal diseases in wildlife and agricultural environments.
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Affiliation(s)
- Yaping Lu
- Jilin Provincial Key Laboratory of Animal Resource Conservation and Utilization, Northeast Normal University, Changchun, China
- Key Laboratory of Vegetation Ecology, Ministry of Education, Changchun, China
| | - Huilan Ren
- Jilin Provincial Key Laboratory of Animal Resource Conservation and Utilization, Northeast Normal University, Changchun, China
- Key Laboratory of Vegetation Ecology, Ministry of Education, Changchun, China
| | - Zhongle Li
- College of Animal Science and Technology, Jilin Agricultural University, Changchun, China
| | - Haixia Leng
- Jilin Provincial Key Laboratory of Animal Resource Conservation and Utilization, Northeast Normal University, Changchun, China
| | - Aoqiang Li
- School of Life Sciences, Central China Normal University, Wuhan, China
| | - Wentao Dai
- Jilin Provincial Key Laboratory of Animal Resource Conservation and Utilization, Northeast Normal University, Changchun, China
| | - Long Huang
- Jilin Provincial Key Laboratory of Animal Resource Conservation and Utilization, Northeast Normal University, Changchun, China
| | - Jiang Feng
- Jilin Provincial Key Laboratory of Animal Resource Conservation and Utilization, Northeast Normal University, Changchun, China
- College of Animal Science and Technology, Jilin Agricultural University, Changchun, China
| | - Keping Sun
- Jilin Provincial Key Laboratory of Animal Resource Conservation and Utilization, Northeast Normal University, Changchun, China
- Key Laboratory of Vegetation Ecology, Ministry of Education, Changchun, China
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Whiting-Fawcett F, Blomberg AS, Troitsky T, Meierhofer MB, Field KA, Puechmaille SJ, Lilley TM. A Palearctic view of a bat fungal disease. CONSERVATION BIOLOGY : THE JOURNAL OF THE SOCIETY FOR CONSERVATION BIOLOGY 2024:e14265. [PMID: 38616727 DOI: 10.1111/cobi.14265] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/20/2023] [Revised: 01/02/2024] [Accepted: 01/20/2024] [Indexed: 04/16/2024]
Abstract
The fungal infection causing white-nose disease in hibernating bats in North America has resulted in dramatic population declines of affected species, since the introduction of the causative agent Pseudogymnoascus destructans. The fungus is native to the Palearctic, where it also infects several bat species, yet rarely causes severe pathology or the death of the host. Pseudogymnoascus destructans infects bats during hibernation by invading and digesting the skin tissue, resulting in the disruption of torpor patterns and consequent emaciation. Relations among pathogen, host, and environment are complex, and individuals, populations, and species respond to the fungal pathogen in different ways. For example, the Nearctic Myotis lucifugus responds to infection by mounting a robust immune response, leading to immunopathology often contributing to mortality. In contrast, the Palearctic M. myotis shows no significant immunological response to infection. This lack of a strong response, resulting from the long coevolution between the hosts and the pathogen in the pathogen's native range, likely contributes to survival in tolerant species. After more than 15 years since the initial introduction of the fungus to North America, some of the affected populations are showing signs of recovery, suggesting that the fungus, hosts, or both are undergoing processes that may eventually lead to coexistence. The suggested or implemented management methods of the disease in North America have encompassed, for example, the use of probiotics and fungicides, vaccinations, and modifying the environmental conditions of the hibernation sites to limit the growth of the pathogen, intensity of infection, or the hosts' responses to it. Based on current knowledge from Eurasia, policy makers and conservation managers should refrain from disrupting the ongoing evolutionary processes and adopt a holistic approach to managing the epizootic.
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Affiliation(s)
- F Whiting-Fawcett
- Department of Evolution, Ecology and Behaviour, University of Liverpool, Liverpool, UK
- BatLab Finland, Finnish Museum of Natural History, University of Helsinki, Helsinki, Finland
| | - A S Blomberg
- BatLab Finland, Finnish Museum of Natural History, University of Helsinki, Helsinki, Finland
| | - T Troitsky
- BatLab Finland, Finnish Museum of Natural History, University of Helsinki, Helsinki, Finland
| | - M B Meierhofer
- BatLab Finland, Finnish Museum of Natural History, University of Helsinki, Helsinki, Finland
| | - K A Field
- Department of Biology, Bucknell University, Lewisburg, Pennsylvania, USA
| | - S J Puechmaille
- Institut des Sciences de l'Évolution Montpellier (ISEM), University of Montpellier, CNRS, EPHE, IRD, Montpellier, France
- Institut Universitaire de France, Paris, France
| | - T M Lilley
- BatLab Finland, Finnish Museum of Natural History, University of Helsinki, Helsinki, Finland
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Kearns PJ, Winter AS, Woodhams DC, Northup DE. The Mycobiome of Bats in the American Southwest Is Structured by Geography, Bat Species, and Behavior. MICROBIAL ECOLOGY 2023; 86:1565-1574. [PMID: 37126126 DOI: 10.1007/s00248-023-02230-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/03/2022] [Accepted: 04/23/2023] [Indexed: 06/19/2023]
Abstract
Bats are widespread mammals that play key roles in ecosystems as pollinators and insectivores. However, there is a paucity of information about bat-associated microbes, in particular their fungal communities, despite the important role microbes play in host health and overall host function. The emerging fungal disease, white-nose syndrome, presents a potential challenge to the bat microbiome and understanding healthy bat-associated taxa will provide valuable information about potential microbiome-pathogen interactions. To address this knowledge gap, we collected 174 bat fur/skin swabs from 14 species of bats captured in five locations in New Mexico and Arizona and used high-throughput sequencing of the fungal internal transcribed (ITS) region to characterize bat-associated fungal communities. Our results revealed a highly heterogeneous bat mycobiome that was structured by geography and bat species. Furthermore, our data suggest that bat-associated fungal communities are affected by bat foraging, indicating the bat skin microbiota is dynamic on short time scales. Finally, despite the strong effects of site and species, we found widespread and abundant taxa from several taxonomic groups including the genera Alternaria and Metschnikowia that have the potential to be inhibitory towards fungal and bacterial pathogens.
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Affiliation(s)
- Patrick J Kearns
- Department of Biology, University of Massachusetts Boston, Boston, MA, 02125, USA.
| | - Ara S Winter
- Department of Biology, University of New Mexico, Albuquerque, NM, 87131, USA
| | - Douglas C Woodhams
- Department of Biology, University of Massachusetts Boston, Boston, MA, 02125, USA
| | - Diana E Northup
- Department of Biology, University of New Mexico, Albuquerque, NM, 87131, USA
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4
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Gabriel KT, McDonald AG, Lutsch KE, Pattavina PE, Morris KM, Ferrall EA, Crow SA, Cornelison CT. Development of a multi-year white-nose syndrome mitigation strategy using antifungal volatile organic compounds. PLoS One 2022; 17:e0278603. [PMID: 36454924 PMCID: PMC9714803 DOI: 10.1371/journal.pone.0278603] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2022] [Accepted: 11/19/2022] [Indexed: 12/03/2022] Open
Abstract
Pseudogymnoascus destructans is a fungal pathogen responsible for a deadly disease among North American bats known as white-nose syndrome (WNS). Since detection of WNS in the United States in 2006, its rapid spread and high mortality has challenged development of treatment and prevention methods, a significant objective for wildlife management agencies. In an effort to mitigate precipitous declines in bat populations due to WNS, we have developed and implemented a multi-year mitigation strategy at Black Diamond Tunnel (BDT), Georgia, singly known as one of the most substantial winter colony sites for tricolored bats (Perimyotis subflavus), with pre-WNS abundance exceeding 5000 individuals. Our mitigation approach involved in situ treatment of bats at the colony level through aerosol distribution of antifungal volatile organic compounds (VOCs) that demonstrated an in vitro ability to inhibit P. destructans conidia germination and mycelial growth through contact-independent exposure. The VOCs evaluated have been identified from microbes inhabiting naturally-occurring fungistatic soils and endophytic fungi. These VOCs are of low toxicity to mammals and have been observed to elicit antagonism of P. destructans at low gaseous concentrations. Cumulatively, our observations resolved no detrimental impact on bat behavior or health, yet indicated a potential for attenuation of WNS related declines at BDT and demonstrated the feasibility of this novel disease management approach.
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Affiliation(s)
- Kyle T. Gabriel
- Department of Molecular and Cellular Biology, Kennesaw State University, Kennesaw, Georgia, United States of America
- * E-mail:
| | - Ashley G. McDonald
- Department of Molecular and Cellular Biology, Kennesaw State University, Kennesaw, Georgia, United States of America
| | - Kelly E. Lutsch
- Department of Molecular and Cellular Biology, Kennesaw State University, Kennesaw, Georgia, United States of America
| | - Peter E. Pattavina
- United States Fish and Wildlife Service, Ecological Services, Athens, Georgia, United States of America
| | - Katrina M. Morris
- Georgia Department of Natural Resources, Wildlife Resources Division, Wildlife Conservation Section, Social Circle, Georgia, United States of America
| | - Emily A. Ferrall
- Georgia Department of Natural Resources, Wildlife Resources Division, Wildlife Conservation Section, Social Circle, Georgia, United States of America
| | - Sidney A. Crow
- Department of Biology, Georgia State University, Atlanta, Georgia, United States of America
| | - Christopher T. Cornelison
- Department of Molecular and Cellular Biology, Kennesaw State University, Kennesaw, Georgia, United States of America
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Kwait R, Kerwin K, Herzog C, Bennett J, Padhi S, Zoccolo I, Maslo B. Whole‐room ultraviolet sanitization as a method for the site‐level treatment of
Pseudogymnoascus destructans. CONSERVATION SCIENCE AND PRACTICE 2022. [DOI: 10.1111/csp2.623] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Affiliation(s)
- Robert Kwait
- Department of Ecology, Evolution, and Natural Resources, Rutgers the State University of New Jersey New Brunswick New Jersey USA
| | - Kathleen Kerwin
- Department of Ecology, Evolution, and Natural Resources, Rutgers the State University of New Jersey New Brunswick New Jersey USA
| | - Carl Herzog
- New York State Department of Environmental Conservation Albany New York USA
| | - Joan Bennett
- Department of Plant Biology and Pathology Rutgers, the State University of New Jersey New Brunswick New Jersey USA
| | - Sally Padhi
- Department of Plant Biology and Pathology Rutgers, the State University of New Jersey New Brunswick New Jersey USA
| | - Isabelle Zoccolo
- Department of Ecology, Evolution, and Natural Resources, Rutgers the State University of New Jersey New Brunswick New Jersey USA
| | - Brooke Maslo
- Department of Ecology, Evolution, and Natural Resources, Rutgers the State University of New Jersey New Brunswick New Jersey USA
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Doty AC, Wilson AD, Forse LB, Risch TS. Biomarker Metabolites Discriminate between Physiological States of Field, Cave and White-nose Syndrome Diseased Bats. SENSORS 2022; 22:s22031031. [PMID: 35161777 PMCID: PMC8840073 DOI: 10.3390/s22031031] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/05/2022] [Revised: 01/21/2022] [Accepted: 01/26/2022] [Indexed: 01/27/2023]
Abstract
Analysis of volatile organic compound (VOC) emissions using electronic-nose (e-nose) devices has shown promise for early detection of white-nose syndrome (WNS) in bats. Tricolored bats, Perimyotis subflavus, from three separate sampling groups defined by environmental conditions, levels of physical activity, and WNS-disease status were captured temporarily for collection of VOC emissions to determine relationships between these combinations of factors and physiological states, Pseudogymnoascus destructans (Pd)-infection status, and metabolic conditions. Physiologically active (non-torpid) healthy individuals were captured outside of caves in Arkansas and Louisiana. In addition, healthy and WNS-diseased torpid bats were sampled within caves in Arkansas. Whole-body VOC emissions from bats were collected using portable air-collection and sampling-chamber devices in tandem. Electronic aroma-detection data using three-dimensional Principal Component Analysis provided strong evidence that the three groups of bats had significantly different e-nose aroma signatures, indicative of different VOC profiles. This was confirmed by differences in peak numbers, peak areas, and tentative chemical identities indicated by chromatograms from dual-column GC-analyses. The numbers and quantities of VOCs present in whole-body emissions from physiologically active healthy field bats were significantly greater than those of torpid healthy and diseased cave bats. Specific VOCs were identified as chemical biomarkers of healthy and diseased states, environmental conditions (outside and inside of caves), and levels of physiological activity. These results suggest that GC/E-nose dual-technologies based on VOC-detection and analyses of physiological states, provide noninvasive alternative means for early assessments of Pd-infection, WNS-disease status, and other physiological states.
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Affiliation(s)
- Anna C. Doty
- Department of Biology, California State University Bakersfield, Bakersfield, CA 93311, USA
- Department of Biological Sciences, Arkansas State University, Jonesboro, AR 72467, USA;
- Correspondence: ; Tel.: +1-661-654-6836
| | - A. Dan Wilson
- Pathology Department, Southern Hardwoods Laboratory, Center for Forest Genetics & Ecosystems Biology, Southern Research Station, USDA Forest Service, 432 Stoneville Road, Stoneville, MS 38776, USA; (A.D.W.); (L.B.F.)
| | - Lisa B. Forse
- Pathology Department, Southern Hardwoods Laboratory, Center for Forest Genetics & Ecosystems Biology, Southern Research Station, USDA Forest Service, 432 Stoneville Road, Stoneville, MS 38776, USA; (A.D.W.); (L.B.F.)
| | - Thomas S. Risch
- Department of Biological Sciences, Arkansas State University, Jonesboro, AR 72467, USA;
- Arkansas Biosciences Institute, Arkansas State University, Jonesboro, AR 72467, USA
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Korn VL, Pennerman KK, Padhi S, Bennett JW. Trans-2-hexenal downregulates several pathogenicity genes of Pseudogymnoascus destructans, the causative agent of white-nose syndrome in bats. J Ind Microbiol Biotechnol 2021; 48:kuab060. [PMID: 34415032 PMCID: PMC8788850 DOI: 10.1093/jimb/kuab060] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2021] [Accepted: 08/13/2021] [Indexed: 11/29/2022]
Abstract
White-nose syndrome is an emergent wildlife disease that has killed millions of North American bats. It is caused by Pseudogymnoascus destructans, a cold-loving, invasive fungal pathogen that grows on bat tissues and disrupts normal hibernation patterns. Previous work identified trans-2-hexenal as a fungistatic volatile compound that potentially could be used as a fumigant against P. destructans in bat hibernacula. To determine the physiological responses of the fungus to trans-2-hexenal exposure, we characterized the P. destructans transcriptome in the presence and absence of trans-2-hexenal. Specifically, we analyzed the effects of sublethal concentrations (5 μmol/L, 10 μmol/L, and 20 μmol/L) of gas-phase trans-2-hexenal of the fungus grown in liquid culture. Among the three treatments, a total of 407 unique differentially expressed genes (DEGs) were identified, of which 74 were commonly affected across all three treatments, with 44 upregulated and 30 downregulated. Downregulated DEGs included several probable virulence genes including those coding for a high-affinity iron permease, a superoxide dismutase, and two protein-degrading enzymes. There was an accompanying upregulation of an ion homeostasis gene, as well as several genes involved in transcription, translation, and other essential cellular processes. These data provide insights into the mechanisms of action of trans-2-hexenal as an anti-fungal fumigant that is active at cold temperatures and will guide future studies on the molecular mechanisms by which six carbon volatiles inhibit growth of P. destructans and other pathogenic fungi.
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Affiliation(s)
| | - Kayla K Pennerman
- Joint Institute for Food Safety and Applied Nutrition, University of Maryland, College Park, MD 20742, USA
| | - Sally Padhi
- Department of Plant Biology, Rutgers University, The State University of New Jersey, New Brunswick, NJ 08901, USA
| | - Joan W Bennett
- Department of Plant Biology, Rutgers University, The State University of New Jersey, New Brunswick, NJ 08901, USA
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Abstract
The recent introduction of Pseudogymnoascus destructans (the fungal pathogen that causes white-nose syndrome in bats) from Eurasia to North America has resulted in the collapse of North American bat populations and restructured species communities. The long evolutionary history between P. destructans and bats in Eurasia makes understanding host life history essential to uncovering the ecology of P. destructans. In this Review, we combine information on pathogen and host biology to understand the patterns of P. destructans spread, seasonal transmission ecology, the pathogenesis of white-nose syndrome and the cross-scale impact from individual hosts to ecosystems. Collectively, this research highlights how early pathogen detection and quantification of host impacts has accelerated the understanding of this newly emerging infectious disease.
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Urbina J, Chestnut T, Allen JM, Levi T. Pseudogymnoascus destructans growth in wood, soil and guano substrates. Sci Rep 2021; 11:763. [PMID: 33436940 PMCID: PMC7804951 DOI: 10.1038/s41598-020-80707-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2020] [Accepted: 12/24/2020] [Indexed: 12/31/2022] Open
Abstract
Understanding how a pathogen can grow on different substrates and how this growth impacts its dispersal are critical to understanding the risks and control of emerging infectious diseases. Pseudogymnoascus destructans (Pd) causes white-nose syndrome (WNS) in many bat species and can persist in, and transmit from, the environment. We experimentally evaluated Pd growth on common substrates to better understand mechanisms of pathogen persistence, transmission and viability. We inoculated autoclaved guano, fresh guano, soil, and wood with live Pd fungus and evaluated (1) whether Pd grows or persists on each (2) if spores of the fungus remain viable 4 months after inoculation on each substrate, and (3) whether detection and quantitation of Pd on swabs is sensitive to the choice to two commonly used DNA extraction kits. After inoculating each substrate with 460,000 Pd spores, we collected ~ 0.20 g of guano and soil, and swabs from wood every 16 days for 64 days to quantify pathogen load through time using real-time qPCR. We detected Pd on all substrates over the course of the experiment. We observed a tenfold increase in pathogen loads on autoclaved guano and persistence but not growth in fresh guano. Pathogen loads increased marginally on wood but declined ~ 60-fold in soil. After four months, apparently viable spores were harvested from all substrates but germination did not occur from fresh guano. We additionally found that detection and quantitation of Pd from swabs of wood surfaces is sensitive to the DNA extraction method. The commonly used PrepMan Ultra Reagent protocol yielded substantially less DNA than did the QIAGEN DNeasy Blood and Tissue Kit. Notably the PrepMan Ultra Reagent failed to detect Pd in many wood swabs that were detected by QIAGEN and were subsequently found to contain substantial live conidia. Our results indicate that Pd can persist or even grow on common environmental substrates with results dependent on whether microbial competitors have been eliminated. Although we observed clear rapid declines in Pd on soil, viable spores were harvested four months after inoculation. These results suggest that environmental substrates and guano can in general serve as infectious environmental reservoirs due to long-term persistence, and even growth, of live Pd. This should inform management interventions to sanitize or modify structures to reduce transmission risk as well early detection rapid response (EDRR) planning.
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Affiliation(s)
- Jenny Urbina
- Department of Fisheries and Wildlife, Oregon State University, 2820 SW Campus Way, Nash Hall, Corvallis, OR, 97331, USA.
| | - Tara Chestnut
- National Park Service, Mount Rainier National Park, Ashford, WA, USA
| | - Jennifer M Allen
- Department of Fisheries and Wildlife, Oregon State University, 2820 SW Campus Way, Nash Hall, Corvallis, OR, 97331, USA
| | - Taal Levi
- Department of Fisheries and Wildlife, Oregon State University, 2820 SW Campus Way, Nash Hall, Corvallis, OR, 97331, USA
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Micalizzi EW, Smith ML. Volatile organic compounds kill the white-nose syndrome fungus, Pseudogymnoascus destructans, in hibernaculum sediment. Can J Microbiol 2020; 66:593-599. [PMID: 32485113 DOI: 10.1139/cjm-2020-0071] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Pseudogymnoascus destructans, the fungal pathogen that causes white-nose syndrome, has killed millions of bats across eastern North America and continues to threaten new bat populations. The spread and persistence of P. destructans has likely been worsened by the ability of this fungus to grow as a saprotroph in the hibernaculum environment. Reducing the environmental growth of P. destructans may improve bat survival. Volatile organic compounds (VOCs) are attractive candidates to target environmental P. destructans, as they can permeate through textured environments that may be difficult to thoroughly contact with other control mechanisms. We tested in hibernaculum sediment the performance of VOCs that were previously shown to inhibit P. destructans growth in agar cultures and examined the inhibition kinetics and specificity of these compounds. Three VOCs, 2-methyl-1-butanol, 2-methyl-1-propanol, and 1-pentanol, were fungicidal towards P. destructans in hibernaculum sediment, fast-acting, and had greater effects against P. destructans than other Pseudogymnoascus species. Our results suggest that use of these VOCs may be considered further as an effective management strategy to reduce the environmental exposure of bats to P. destructans in hibernacula.
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Affiliation(s)
- Emma W Micalizzi
- Department of Biology, Nesbitt Building, Carleton University, 1125 Colonel By Drive, Ottawa, ON K1S 5B6, Canada.,Department of Biology, Nesbitt Building, Carleton University, 1125 Colonel By Drive, Ottawa, ON K1S 5B6, Canada
| | - Myron L Smith
- Department of Biology, Nesbitt Building, Carleton University, 1125 Colonel By Drive, Ottawa, ON K1S 5B6, Canada.,Department of Biology, Nesbitt Building, Carleton University, 1125 Colonel By Drive, Ottawa, ON K1S 5B6, Canada
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11
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Rusman Y, Wilson MB, Williams JM, Held BW, Blanchette RA, Anderson BN, Lupfer CR, Salomon CE. Antifungal Norditerpene Oidiolactones from the Fungus Oidiodendron truncatum, a Potential Biocontrol Agent for White-Nose Syndrome in Bats. JOURNAL OF NATURAL PRODUCTS 2020; 83:344-353. [PMID: 31986046 DOI: 10.1021/acs.jnatprod.9b00789] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
White-nose syndrome (WNS) is a devastating disease of hibernating bats caused by the fungus Pseudogymnoascus destructans. We obtained 383 fungal and bacterial isolates from the Soudan Iron Mine, an important bat hibernaculum in Minnesota, then screened this library for antifungal activity to develop biological control treatments for WNS. An extract from the fungus Oidiodendron truncatum was subjected to bioassay-guided fractionation, which led to the isolation of 14 norditerpene and three anthraquinone metabolites. Ten of these compounds were previously described in the literature, and here we present the structures of seven new norditerpene analogues. Additionally, this is the first report of 4-chlorophyscion from a natural source, previously identified as a semisynthetic product. The compounds PR 1388 and LL-Z1271α were the only inhibitors of P. destructans (MIC = 7.5 and 15 μg/mL, respectively). Compounds were tested for cytotoxicity against fibroblast cell cultures obtained from Myotis septentrionalis (northern long eared bat) and M. grisescens (gray bat) using a standard MTT viability assay. The most active antifungal compound, PR 1388, was nontoxic toward cells from both bat species (IC50 > 100 μM). We discuss the implications of these results in the context of the challenges and logistics of developing a substrate treatment or prophylactic for WNS.
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Affiliation(s)
- Yudi Rusman
- Center for Drug Design , University of Minnesota , Minneapolis , Minnesota 55405 , United States
| | - Michael B Wilson
- Center for Drug Design , University of Minnesota , Minneapolis , Minnesota 55405 , United States
| | - Jessica M Williams
- Center for Drug Design , University of Minnesota , Minneapolis , Minnesota 55405 , United States
| | - Benjamin W Held
- Department of Plant Pathology , University of Minnesota , Minneapolis , Minnesota 55405 , United States
| | - Robert A Blanchette
- Department of Plant Pathology , University of Minnesota , Minneapolis , Minnesota 55405 , United States
| | - Brianna N Anderson
- Department of Biology , Missouri State University , Springfield , Missouri 65897 , United States
| | - Christopher R Lupfer
- Department of Biology , Missouri State University , Springfield , Missouri 65897 , United States
| | - Christine E Salomon
- Center for Drug Design , University of Minnesota , Minneapolis , Minnesota 55405 , United States
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12
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Gabriel KT, Neville JJ, Pierce GE, Cornelison CT. Lipolytic Activity and the Utilization of Fatty Acids Associated with Bat Sebum by Pseudogymnoascus destructans. Mycopathologia 2019; 184:625-636. [PMID: 31529298 DOI: 10.1007/s11046-019-00381-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2019] [Accepted: 08/28/2019] [Indexed: 01/13/2023]
Abstract
Pseudogymnoascus destructans is the causative agent of a fungal infection of bats known as white-nose syndrome (WNS). Since its discovery in 2006, it has been responsible for precipitous declines of several species of cave-dwelling North American bats. While numerous advancements in the understanding of the disease processes underlying WNS have been made in recent years, there are still many aspects of WNS, particularly with respect to pathogen virulence, that remain unknown. In this preliminary investigation, we sought to further elucidate the disease cycle by concentrating on the pathogen, with specific focus on its ability to utilize lipids that compose bat wing sebum and are found in wing membranes, as a substrate for energy and growth. In vitro growth experiments were conducted with the three most common fatty acids that comprise bat sebum: oleic, palmitic, and stearic acids. None of the fatty acids were observed to contribute a significant difference in mean growth from controls grown on SDA, although morphological differences were observed in several instances. Additionally, as an accompaniment to the growth experiments, bat wing explants from Perimyotis subflavus and Eptesicus fuscus were fluorescently stained to visualize the difference in distribution of 16- and 18-carbon chain fatty acids in the wing membrane. Which substrates contribute to the growth of P. destructans is important to understanding the progressive impact P. destructans has on bat health through the course of the disease cycle.
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Affiliation(s)
- Kyle T Gabriel
- Division of Research and Advanced Studies, Kennesaw State University, Kennesaw, GA, USA.
| | - John J Neville
- Department of Molecular and Cellular Biology, Kennesaw State University, Kennesaw, GA, USA
| | - George E Pierce
- Department of Biology, Georgia State University, Atlanta, GA, USA
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Lilley TM, Prokkola JM, Blomberg AS, Paterson S, Johnson JS, Turner GG, Bartonička T, Bachorec E, Reeder DM, Field KA. Resistance is futile: RNA-sequencing reveals differing responses to bat fungal pathogen in Nearctic Myotis lucifugus and Palearctic Myotis myotis. Oecologia 2019; 191:295-309. [PMID: 31506746 PMCID: PMC6763535 DOI: 10.1007/s00442-019-04499-6] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2019] [Accepted: 08/30/2019] [Indexed: 12/18/2022]
Abstract
Abstract Resistance and tolerance allow organisms to cope with potentially life-threatening pathogens. Recently introduced pathogens initially induce resistance responses, but natural selection favors the development of tolerance, allowing for a commensal relationship to evolve. Mycosis by Pseudogymnoascus destructans, causing white-nose syndrome (WNS) in Nearctic hibernating bats, has resulted in population declines since 2006. The pathogen, which spread from Europe, has infected species of Palearctic Myotis for a longer period. We compared ecologically relevant responses to the fungal infection in the susceptible Nearctic M. lucifugus and less susceptible Palearctic M. myotis, to uncover factors contributing to survival differences in the two species. Samples were collected from euthermic bats during arousal from hibernation, a naturally occurring phenomenon, during which transcriptional responses are activated. We compared the whole-transcriptome responses in wild bats infected with P. destructans hibernating in their natural habitat. Our results show dramatically different local transcriptional responses to the pathogen between uninfected and infected samples from the two species. Whereas we found 1526 significantly upregulated or downregulated transcripts in infected M. lucifugus, only one transcript was downregulated in M. myotis. The upregulated response pathways in M. lucifugus include immune cell activation and migration, and inflammatory pathways, indicative of an unsuccessful attempt to resist the infection. In contrast, M. myotis appears to tolerate P. destructans infection by not activating a transcriptional response. These host-microbe interactions determine pathology, contributing to WNS susceptibility, or commensalism, promoting tolerance to fungal colonization during hibernation that favors survival. Graphic abstract ![]()
Electronic supplementary material The online version of this article (10.1007/s00442-019-04499-6) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Thomas M Lilley
- Finnish Museum of Natural History, University of Helsinki, Helsinki, Finland.
- Institute of Integrative Biology, University of Liverpool, Liverpool, UK.
| | - Jenni M Prokkola
- Institute of Integrative Biology, University of Liverpool, Liverpool, UK
| | | | - Steve Paterson
- Institute of Integrative Biology, University of Liverpool, Liverpool, UK
| | - Joseph S Johnson
- Department of Biological Sciences, Ohio University, Athens, OH, USA
| | | | - Tomáš Bartonička
- Department of Botany and Zoology, Masaryk University, Brno, Czech Republic
| | - Erik Bachorec
- Department of Botany and Zoology, Masaryk University, Brno, Czech Republic
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14
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Virally-vectored vaccine candidates against white-nose syndrome induce anti-fungal immune response in little brown bats (Myotis lucifugus). Sci Rep 2019; 9:6788. [PMID: 31043669 PMCID: PMC6494898 DOI: 10.1038/s41598-019-43210-w] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2018] [Accepted: 04/17/2019] [Indexed: 12/24/2022] Open
Abstract
White-nose syndrome (WNS) caused by the fungus, Pseudogymnoascus destructans (Pd) has killed millions of North American hibernating bats. Currently, methods to prevent the disease are limited. We conducted two trials to assess potential WNS vaccine candidates in wild-caught Myotis lucifugus. In a pilot study, we immunized bats with one of four vaccine treatments or phosphate-buffered saline (PBS) as a control and challenged them with Pd upon transfer into hibernation chambers. Bats in one vaccine-treated group, that received raccoon poxviruses (RCN) expressing Pd calnexin (CAL) and serine protease (SP), developed WNS at a lower rate (1/10) than other treatments combined (14/23), although samples sizes were small. The results of a second similar trial provided additional support for this observation. Bats vaccinated orally or by injection with RCN-CAL and RCN-SP survived Pd challenge at a significantly higher rate (P = 0.01) than controls. Using RT-PCR and flow cytometry, combined with fluorescent in situ hybridization, we determined that expression of IFN-γ transcripts and the number of CD4 + T-helper cells transcribing this gene were elevated (P < 0.10) in stimulated lymphocytes from surviving vaccinees (n = 15) compared to controls (n = 3). We conclude that vaccination with virally-vectored Pd antigens induced antifungal immunity that could potentially protect bats against WNS.
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15
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Gabriel KT, Kartforosh L, Crow SA, Cornelison CT. Antimicrobial Activity of Essential Oils Against the Fungal Pathogens Ascosphaera apis and Pseudogymnoascus destructans. Mycopathologia 2018; 183:921-934. [PMID: 30306397 DOI: 10.1007/s11046-018-0298-x] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2018] [Accepted: 09/24/2018] [Indexed: 01/14/2023]
Abstract
Fungal pathogens are a growing worldwide concern. Declines in a number of economically and agriculturally important plant and animal species pose a significant threat to both biodiversity and food security. Although many effective antifungal agents have been identified, their toxicity often precludes their use with food products or sensitive animal species. This has prompted the exploration of natural products as effective treatment compounds. In the present study, several essential oils were tested for their capacity to limit the growth of the fungal pathogens Ascosphaera apis and Pseudogymnoascus destructans, the causative agents of chalkbrood disease among honey bee larvae and white-nose syndrome among bats, respectively. Essential oils of cinnamon bark, citronella, lemongrass, and orange were exposed to A. apis in contact-dependent oil-agar suspensions as well as in contact-independent shared airspaces. Essential oils of cinnamon bark, citronella, and lemongrass were exposed to P. destructans in contact-dependent oil-agar suspensions. All compounds were found to significantly inhibit mycelial growth at low concentrations, suggesting the potential for these natural products to be used for controlling these and other select fungal pathogens.
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Affiliation(s)
- Kyle T Gabriel
- Division of Research and Advanced Study, Kennesaw State University, Kennesaw, GA, USA.
| | - Leila Kartforosh
- Department of Biology, Georgia State University, Atlanta, GA, USA
| | - Sidney A Crow
- Department of Biology, Georgia State University, Atlanta, GA, USA
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16
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Singh A, Lasek-Nesselquist E, Chaturvedi V, Chaturvedi S. Trichoderma polysporum selectively inhibits white-nose syndrome fungal pathogen Pseudogymnoascus destructans amidst soil microbes. MICROBIOME 2018; 6:139. [PMID: 30089518 PMCID: PMC6083572 DOI: 10.1186/s40168-018-0512-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/18/2018] [Accepted: 07/02/2018] [Indexed: 05/29/2023]
Abstract
BACKGROUND Pseudogymnoascus destructans (Pd), the causative fungal agent of white-nose syndrome (WNS), has led to the deaths of millions of hibernating bats in the United States of America (USA) and Canada. Efficient strategies are needed to decontaminate Pd from the bat hibernacula to interrupt the disease transmission cycle without affecting the native microbes. Previously, we discovered a novel Trichoderma polysporum (Tp) strain (WPM 39143), which inhibited the growth of Pd in autoclaved soil samples. In the present investigation, we used culture-based approaches to determine Tp-induced killing of native and enriched Pd in the natural soil of two bat hibernacula. We also assessed the impact of Tp treatment on native microbial communities by metagenomics. RESULTS Our results demonstrated that Tp at the concentration of 105 conidia/g soil caused 100% killing of native Pd in culture within 5 weeks of incubation. A 10-fold higher concentration of Tp (106 conidia/g soil) killed an enriched Pd population (105 conidia/g soil). The 12,507 fungal operational taxonomic units (OTUs, dominated by Ascomycota and Basidiomycota) and 27,427 bacterial OTUs (dominated by Acidobacteria and Proteobacteria) comprised the native soil microbes of the two bat hibernacula. No significant differences in fungal and bacterial relative abundances were observed between untreated and Tp-treated soil (105 Tp conidia/g soil, p ≤ 0.05). CONCLUSIONS Our results suggest that Tp-induced killing of Pd is highly specific, with minimal to no impact on the indigenous microbes present in the soil samples. These findings provide the scientific rationale for the field trials of Tp in the WNS-affected hibernacula for the effective decontamination of Pd and the control of WNS.
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Affiliation(s)
- Amanpreet Singh
- Mycology Laboratory, Wadsworth Center, New York State Department of Health, 120 New Scotland Avenue, Albany, NY, 12208, USA
| | | | - Vishnu Chaturvedi
- Mycology Laboratory, Wadsworth Center, New York State Department of Health, 120 New Scotland Avenue, Albany, NY, 12208, USA
- Department of Biomedical Sciences, School of Public Health, University at Albany, Albany, NY, USA
| | - Sudha Chaturvedi
- Mycology Laboratory, Wadsworth Center, New York State Department of Health, 120 New Scotland Avenue, Albany, NY, 12208, USA.
- Department of Biomedical Sciences, School of Public Health, University at Albany, Albany, NY, USA.
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17
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Woodhams DC, LaBumbard BC, Barnhart KL, Becker MH, Bletz MC, Escobar LA, Flechas SV, Forman ME, Iannetta AA, Joyce MD, Rabemananjara F, Gratwicke B, Vences M, Minbiole KPC. Prodigiosin, Violacein, and Volatile Organic Compounds Produced by Widespread Cutaneous Bacteria of Amphibians Can Inhibit Two Batrachochytrium Fungal Pathogens. MICROBIAL ECOLOGY 2018; 75:1049-1062. [PMID: 29119317 DOI: 10.1007/s00248-017-1095-7] [Citation(s) in RCA: 70] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/27/2017] [Accepted: 10/19/2017] [Indexed: 06/07/2023]
Abstract
Symbiotic bacteria can produce secondary metabolites and volatile compounds that contribute to amphibian skin defense. Some of these symbionts have been used as probiotics to treat or prevent the emerging disease chytridiomycosis. We examined 20 amphibian cutaneous bacteria for the production of prodigiosin or violacein, brightly colored defense compounds that pigment the bacteria and have characteristic spectroscopic properties making them readily detectable, and evaluated the antifungal activity of these compounds. We detected violacein from all six isolates of Janthinobacterium lividum on frogs from the USA, Switzerland, and on captive frogs originally from Panama. We detected prodigiosin from five isolates of Serratia plymuthica or S. marcescens, but not from four isolates of S. fonticola or S. liquefaciens. All J. lividum isolates produced violacein when visibly purple, while prodigiosin was only detected on visibly red Serratia isolates. When applied to cultures of chytrid fungi Batrachochytrium dendrobatidis (Bd) and B. salamandrivorans (Bsal), prodigiosin caused significant growth inhibition, with minimal inhibitory concentrations (MIC) of 10 and 50 μM, respectively. Violacein showed a MIC of 15 μM against both fungi and was slightly more active against Bsal than Bd at lower concentrations. Although neither violacein nor prodigiosin showed aerosol activity and is not considered a volatile organic compound (VOC), J. lividum and several Serratia isolates did produce antifungal VOCs. White Serratia isolates with undetectable prodigiosin levels could still inhibit Bd growth indicating additional antifungal compounds in their chemical arsenals. Similarly, J. lividum can produce antifungal compounds such as indole-3-carboxaldehyde in addition to violacein, and isolates are not always purple, or turn purple under certain growth conditions. When Serratia isolates were grown in the presence of cell-free supernatant (CFS) from the fungi, CFS from Bd inhibited growth of the prodigiosin-producing isolates, perhaps indicative of an evolutionary arms race; Bsal CFS did not inhibit bacterial growth. In contrast, growth of one J. lividum isolate was facilitated by CFS from both fungi. Isolates that grow and continue to produce antifungal compounds in the presence of pathogens may represent promising probiotics for amphibians infected or at risk of chytridiomycosis. In a global analysis, 89% of tested Serratia isolates and 82% of J. lividum isolates were capable of inhibiting Bd and these have been reported from anurans and caudates from five continents, indicating their widespread distribution and potential for host benefit.
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Affiliation(s)
- Douglas C Woodhams
- Biology Department, University of Massachusetts Boston, Boston, MA, 02125, USA.
| | - Brandon C LaBumbard
- Biology Department, University of Massachusetts Boston, Boston, MA, 02125, USA
| | - Kelly L Barnhart
- Biology Department, University of Massachusetts Boston, Boston, MA, 02125, USA
| | - Matthew H Becker
- Smithsonian Conservation Biology Institute, National Zoological Park, Washington, DC, USA
- Department of Biology and Chemistry, Liberty University, Lynchburg, VA, USA
| | - Molly C Bletz
- Biology Department, University of Massachusetts Boston, Boston, MA, 02125, USA
- Zoological Institute, Technische Universität Braunschweig, 38106, Braunschweig, Germany
| | - Laura A Escobar
- School of Sciences, Pontificia Universidad Javeriana, Bogotá, AA 56710, Colombia
| | - Sandra V Flechas
- Department of Biological Sciences, Universidad de los Andes, Bogotá, AA 4976, Colombia
| | - Megan E Forman
- Department of Chemistry, Villanova University, Villanova, PA, 19085, USA
| | - Anthony A Iannetta
- Department of Chemistry, Villanova University, Villanova, PA, 19085, USA
- Department of Chemistry, University of North Carolina, Chapel Hill, NC, 27514, USA
| | - Maureen D Joyce
- Department of Chemistry, Villanova University, Villanova, PA, 19085, USA
| | | | - Brian Gratwicke
- Smithsonian Conservation Biology Institute, National Zoological Park, Washington, DC, USA
| | - Miguel Vences
- Zoological Institute, Technische Universität Braunschweig, 38106, Braunschweig, Germany
| | - Kevin P C Minbiole
- Department of Chemistry, Villanova University, Villanova, PA, 19085, USA.
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18
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Padhi S, Dias I, Korn VL, Bennett JW. Pseudogymnoascus destructans: Causative Agent of White-Nose Syndrome in Bats Is Inhibited by Safe Volatile Organic Compounds. J Fungi (Basel) 2018; 4:jof4020048. [PMID: 29642609 PMCID: PMC6023378 DOI: 10.3390/jof4020048] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2018] [Revised: 03/27/2018] [Accepted: 04/03/2018] [Indexed: 01/12/2023] Open
Abstract
White-nose syndrome (WNS) is caused by Pseudogymnoascus destructans, a psychrophilic fungus that infects hibernating bats and has caused a serious decline in some species. Natural aroma compounds have been used to control growth of fungal food storage pathogens, so we hypothesized that a similar strategy could work for control of P. destructans. The effectiveness of exposure to low concentrations of the vapor phase of four of these compounds was tested on mycelial plugs and conidiospores at temperatures of 5, 10 and 15 °C. Here we report the efficacy of vapor phase mushroom alcohol (1-octen-3-ol) for inhibiting mycelial and conidiospore growth of P. destructans at 0.4 and 0.8 µmol/mL and demonstrate that the R enantiomer of this compound is more effective than the S enantiomer, supporting the finding that biological systems can be sensitive to stereochemistry. Further, we report that vapor phase leaf aldehyde (trans-2-hexenal), a common aroma compound associated with cut grass odors and also the major volatile compound in extra virgin olive oil, is more effective than mushroom alcohol. At 0.05 µmol/mL, trans-2-hexenal is fungicidal to both conidiospores and mycelia of P. destructans.
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Affiliation(s)
- Sally Padhi
- Department of Plant Biology, Rutgers University, 59 Dudley Road, New Brunswick, NJ 08901, USA.
| | - Itamar Dias
- Department of Plant Biology, Rutgers University, 59 Dudley Road, New Brunswick, NJ 08901, USA.
| | - Victoria L Korn
- Department of Plant Biology, Rutgers University, 59 Dudley Road, New Brunswick, NJ 08901, USA.
| | - Joan W Bennett
- Department of Plant Biology, Rutgers University, 59 Dudley Road, New Brunswick, NJ 08901, USA.
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19
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Observed Resiliency of Little Brown Myotis to Long-Term White-Nose Syndrome Exposure. JOURNAL OF FISH AND WILDLIFE MANAGEMENT 2018. [DOI: 10.3996/102017-jfwm-080] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Abstract
White-nose syndrome (WNS) is a disease that has killed millions of bats in eastern North America and has steadily been spreading across the continent. Little brown myotis Myotis lucifugus populations have experienced extensive declines; however, some localized populations have remained resilient, with bats surviving multiple years past initial WNS exposure. These persistent populations may be critical to species recovery, and understanding mechanisms leading to this long-term survival and persistence may provide insight into overall bat and disease management. We monitored a maternity colony of little brown myotis on Fort Drum Military Installation in northern New York between 2006 and 2017 to determine basic demographic parameters and find evidence of what may be leading to resiliency and persistence at this site. Total colony size declined by approximately 88% from 2008 to 2010 due primarily to impacts of WNS. Counts of all adults returning to the colony stabilized during 2010–2014 (mean = 94, range 84–101) and increased after 2014 (mean = 132, range = 108–166). We captured 727 little brown myotis (575 females, 152 males) and banded 534 individuals (389 females, 145 males) at the colony. The majority of sampled bats showed evidence of recent past WNS infection and exposure to Pseudogymnoascus destructans, and we documented pervasive presence and limited viability of the fungus within the colony's main roosting structure. We recaptured 98 individually marked females in years after initial banding, and some individuals survived at least 6 y. Ninety-one percent of all adult females, 93% of recaptured bats, and 90% of 1-y-old females (i.e., bats recaptured the first year after initial capture as juveniles) showed evidence of reproduction during the monitoring period. Using mark–recapture models, we estimated annual survival rates of juvenile and adult little brown myotis during 2009–2016 and examined whether reproductive condition or evidence of recent infection of WNS had any effect on survival. Annual survival rates were similar between juveniles and adults, but highly variable, ranging from 41.0 to 86.5%. Models indicated that neither evidence of recent past exposure to WNS nor reproductive status were related to survival. No one parameter stood out as being responsible for this colony's continued existence, and it is likely that many interwoven factors were responsible for the observed resilience. Although relatively high reproductive effort from all females (i.e., both1-y-old and >1-y-old ) and intermittently suitable survival rates have led to the continued persistence of, and population increases in, this summer colony, mortality from WNS and inherently low reproductive potential still seemed to be limiting population growth. Until there is a better understanding of this overall potential resiliency in little brown myotis, we recommend considering minimizing disturbance and direct human involvement within these persisting populations to allow whatever natural recovery that may be occurring to evolve uninterrupted.
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20
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Lilley TM, Prokkola JM, Johnson JS, Rogers EJ, Gronsky S, Kurta A, Reeder DM, Field KA. Immune responses in hibernating little brown myotis ( Myotis lucifugus) with white-nose syndrome. Proc Biol Sci 2018; 284:rspb.2016.2232. [PMID: 28179513 DOI: 10.1098/rspb.2016.2232] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2016] [Accepted: 01/13/2017] [Indexed: 12/30/2022] Open
Abstract
White-nose syndrome (WNS) is a fungal disease responsible for decimating many bat populations in North America. Pseudogymnoascus destructans (Pd), the psychrophilic fungus responsible for WNS, prospers in the winter habitat of many hibernating bat species. The immune response that Pd elicits in bats is not yet fully understood; antibodies are produced in response to infection by Pd, but they may not be protective and indeed may be harmful. To understand how bats respond to infection during hibernation, we studied the effect of Pd inoculation on the survival and gene expression of captive hibernating Myotis lucifugus with varying pre-hibernation antifungal antibody titres. We investigated gene expression through the transcription of selected cytokine genes (Il6, Il17a, Il1b, Il4 and Ifng) associated with inflammatory, Th1, Th2 and Th17 immune responses in wing tissue and lymph nodes. We found no difference in survival between bats with low and high anti-Pd titres, although anti-Pd antibody production during hibernation differed significantly between infected and uninfected bats. Transcription of Il6 and Il17a was higher in the lymph nodes of infected bats compared with uninfected bats. Increased transcription of these cytokines in the lymph node suggests that a pro-inflammatory immune response to WNS is not restricted to infected tissues and occurs during hibernation. The resulting Th17 response may be protective in euthermic bats, but because it may disrupt torpor, it could be detrimental during hibernation.
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Affiliation(s)
- T M Lilley
- Biology Department, Bucknell University, 1 Dent Drive, Lewisburg, PA 17837, USA.,Biodiversity Unit, University of Turku, 20014 Turku, Finland
| | - J M Prokkola
- Biology Department, Bucknell University, 1 Dent Drive, Lewisburg, PA 17837, USA
| | - J S Johnson
- Biology Department, Bucknell University, 1 Dent Drive, Lewisburg, PA 17837, USA.,Center for Ecology and Evolutionary Studies, Department of Biological Sciences, Ohio University, Athens, OH 45701, USA
| | - E J Rogers
- Biology Department, Bucknell University, 1 Dent Drive, Lewisburg, PA 17837, USA
| | - S Gronsky
- Biology Department, Bucknell University, 1 Dent Drive, Lewisburg, PA 17837, USA
| | - A Kurta
- Biology Department, Eastern Michigan University, Ypsilanti, MI 48197, USA
| | - D M Reeder
- Biology Department, Bucknell University, 1 Dent Drive, Lewisburg, PA 17837, USA
| | - K A Field
- Biology Department, Bucknell University, 1 Dent Drive, Lewisburg, PA 17837, USA
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21
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Gabriel KT, Joseph Sexton D, Cornelison CT. Biomimicry of volatile-based microbial control for managing emerging fungal pathogens. J Appl Microbiol 2018; 124:1024-1031. [PMID: 29240978 DOI: 10.1111/jam.13667] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2017] [Revised: 11/27/2017] [Accepted: 12/05/2017] [Indexed: 11/30/2022]
Abstract
Volatile organic compounds (VOCs) are known to be produced by a wide range of micro-organisms and for a number of purposes. Volatile-based microbial inhibition in environments such as soil is well-founded, with numerous antimicrobial VOCs having been identified. Inhibitory VOCs are of interest as microbial control agents, as low concentrations of gaseous VOCs can elicit significant antimicrobial effects. Volatile organic compounds are organic chemicals typically characterized as having low molecular weight, low solubility in water, and high vapour pressure. Consequently, VOCs readily evaporate to the gaseous phase at standard temperature and pressure. This contact-independent antagonism presents unique advantages over traditional, contact-dependent microbial control methods, including increased surface exposure and reduced environmental persistence. This approach has been the focus of our recent research, with positive results suggesting it may be particularly promising for the management of emerging fungal pathogens, such as the causative agents of white-nose syndrome of bats and snake fungal disease, which are difficult or impossible to treat using traditional approaches. Here, we review the history of volatile-based microbial control, discuss recent progress in formulations that mimic naturally antagonistic VOCs, outline the development of a novel treatment device, and highlight areas where further work is needed to successfully deploy VOCs against existing and emerging fungal pathogens.
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Affiliation(s)
- K T Gabriel
- Division of Research and Advanced Studies, Kennesaw State University, Kennesaw, GA, USA
| | - D Joseph Sexton
- Department of Microbiology, Oregon State University, Corvallis, OR, USA
| | - C T Cornelison
- Division of Research and Advanced Studies, Kennesaw State University, Kennesaw, GA, USA
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22
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Ghosh S, McArthur R, Guo ZC, McKerchar R, Donkor K, Xu J, Cheeptham N. Evidence for Anti-Pseudogymnoascus destructans (Pd) Activity of Propolis. Antibiotics (Basel) 2017; 7:antibiotics7010002. [PMID: 29267199 PMCID: PMC5872113 DOI: 10.3390/antibiotics7010002] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2017] [Revised: 12/05/2017] [Accepted: 12/20/2017] [Indexed: 12/23/2022] Open
Abstract
White-nose syndrome (WNS) in bats, caused by Pseudogymnoascus destructans (Pd), is a cutaneous infection that has devastated North American bat populations since 2007. At present, there is no effective method for controlling this disease. Here, we evaluated the effect of propolis against Pd in vitro. Using Sabouraud dextrose agar (SDA) medium, approximately 1.7 × 10⁷ conidia spores of the Pd strain M3906-2/mL were spread on each plate and grown to form a consistent lawn. A Kirby-Bauer disk diffusion assay was employed using different concentrations of propolis (1%, 2%, 3%, 4%, 5%, 10%, 15%, 20%, 25%), in plates incubated at 8 °C and 15 °C. At 8 °C and 15 °C, as the concentration of propolis increased, there was an increasing zone of inhibition (ZOI), reaching the highest degree at 10% and 25% concentrations, respectively. A germule suppression assay showed a similar effect on Pd conidia germination. A MALDI-TOF-MS analysis of propolis revealed multiple constituents with a potential anti-Pd activity, including cinnamic acid, p-coumaric acid, and dihydrochalcones, which could be further tested for their individual effects. Our study suggests that propolis or its individual constituents might be suitable products against Pd.
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Affiliation(s)
- Soumya Ghosh
- Department of Biological Sciences, Thompson Rivers University, Kamloops, BC V2C 0C8, Canada.
| | - Robyn McArthur
- Department of Biological Sciences, Thompson Rivers University, Kamloops, BC V2C 0C8, Canada.
| | - Zhi Chao Guo
- Department of Biological Sciences, Thompson Rivers University, Kamloops, BC V2C 0C8, Canada.
| | - Rory McKerchar
- Department of Biological Sciences, Thompson Rivers University, Kamloops, BC V2C 0C8, Canada.
| | - Kingsley Donkor
- Department of Biological Sciences, Thompson Rivers University, Kamloops, BC V2C 0C8, Canada.
| | - Jianping Xu
- Department of Biology, McMaster University, Hamilton, ON L8S 4K1 Canada.
| | - Naowarat Cheeptham
- Department of Biological Sciences, Thompson Rivers University, Kamloops, BC V2C 0C8, Canada.
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Maslo B, Stringham OC, Bevan AJ, Brumbaugh A, Sanders C, Hall M, Fefferman NH. High annual survival in infected wildlife populations may veil a persistent extinction risk from disease. Ecosphere 2017. [DOI: 10.1002/ecs2.2001] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Affiliation(s)
- Brooke Maslo
- Department of Ecology, Evolution and Natural Resources, Rutgers; The State University of New Jersey; 14 College Farm Road New Brunswick New Jersey 08901 USA
- Rutgers Cooperative Extension; New Jersey Agricultural Experiment Station, Rutgers; The State University of New Jersey; 88 Lipman Drive New Brunswick New Jersey 08901 USA
| | - Oliver C. Stringham
- Department of Ecology, Evolution and Natural Resources, Rutgers; The State University of New Jersey; 14 College Farm Road New Brunswick New Jersey 08901 USA
| | - Amanda J. Bevan
- Department of Ecology, Evolution and Natural Resources, Rutgers; The State University of New Jersey; 14 College Farm Road New Brunswick New Jersey 08901 USA
| | - Amanda Brumbaugh
- Sanders Environmental, Inc.; 322 Borealis Way Bellefonte Pennsylvania 16823 USA
| | - Chris Sanders
- Sanders Environmental, Inc.; 322 Borealis Way Bellefonte Pennsylvania 16823 USA
| | - MacKenzie Hall
- Endangered and Nongame Species Program; NJ Division of Fish and Wildlife; 1 Van Syckels Road Clinton New Jersey 08809 USA
| | - Nina H. Fefferman
- Ecology & Evolutionary Biology; The University of Tennessee; 1416 Circle Drive Knoxville Tennessee 37996 USA
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24
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Donaldson ME, Davy CM, Willis CKR, McBurney S, Park A, Kyle CJ. Profiling the immunome of little brown myotis provides a yardstick for measuring the genetic response to white-nose syndrome. Evol Appl 2017; 10:1076-1090. [PMID: 29151862 PMCID: PMC5680615 DOI: 10.1111/eva.12514] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2017] [Accepted: 06/26/2017] [Indexed: 12/19/2022] Open
Abstract
White‐nose syndrome (WNS) has devastated populations of hibernating bats in eastern North America, leading to emergency conservation listings for several species including the previously ubiquitous little brown myotis (Myotis lucifugus). However, some bat populations near the epicenter of the WNS panzootic appear to be stabilizing after initial precipitous declines, which could reflect a selective immunogenetic sweep. To investigate the hypothesis that WNS exerts significant selection on the immunome of affected bat populations, we developed a novel, high‐throughput sequence capture assay targeting 138 adaptive, intrinsic, and innate immunity genes of putative adaptive significance, as well as their respective regulatory regions (~370 kbp of genomic sequence/individual). We used the assay to explore baseline immunogenetic variation in M. lucifugus and to investigate whether particular immune genes/variants are associated with WNS susceptibility. We also used our assay to detect 1,038 putatively neutral single nucleotide polymorphisms and characterize contemporary population structure, providing context for the identification of local immunogenetic adaptation. Sequence capture provided a cost‐effective, “all‐in‐one” assay to test for neutral genetic and immunogenetic structure and revealed fine‐scale, baseline immunogenetic differentiation between sampling sites <600 km apart. We identified functional immunogenetic variants in M. lucifugus associated with WNS susceptibility. This study lays the foundations for future investigations of rangewide immunogenetic adaptation to WNS in M. lucifugus and provides a blueprint for studies of evolutionary rescue in other host–pathogen systems.
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Affiliation(s)
- Michael E Donaldson
- Environmental and Life Sciences Graduate Program Trent University Peterborough ON Canada
| | - Christina M Davy
- Environmental and Life Sciences Graduate Program Trent University Peterborough ON Canada.,Wildlife Research and Monitoring Section Ontario Ministry of Natural Resources and Forestry Peterborough ON Canada
| | - Craig K R Willis
- Department of Biology and Centre for Forest Interdisciplinary Research (C-FIR) University of Winnipeg Winnipeg MB Canada
| | - Scott McBurney
- Canadian Wildlife Health Cooperative Atlantic Region Atlantic Veterinary College University of Prince Edward Island Charlottetown PEI Canada
| | - Allysia Park
- Canadian Wildlife Health Cooperative Atlantic Region Atlantic Veterinary College University of Prince Edward Island Charlottetown PEI Canada
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25
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Mutai C, Njuguna J, Ghimire S. Brachiaria Grasses (Brachiaria spp.) harbor a diverse bacterial community with multiple attributes beneficial to plant growth and development. Microbiologyopen 2017. [PMID: 28639414 PMCID: PMC5635169 DOI: 10.1002/mbo3.497] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
Endophytic and plant-associated bacteria were isolated from plants and rhizoplane soil of naturally grown Brachiaria grasses at International Livestock Research Institute in Nairobi, Kenya. Eighty-four bacterial strains were isolated from leaf tissues, root tissues, and rhizoplane soil on nutrient agar and 869 media. All bacterial strains were identified to the lowest possible taxonomic unit using 16S rDNA primers and were characterized for the production of Indole-3-acetic acid, hydrogen cyanide, and ACC deaminase; phosphate solubilization; siderophore production; antifungal properties; and plant biomass production. The 16S rDNA-based identification grouped these 84 bacterial strains into 3 phyla, 5 classes, 8 orders, 12 families, 16 genera, and 50 unique taxa. The four most frequently isolated genera were Pseudomonas (23), Pantoea (17), Acinetobacter (9), and Enterobacter (8). The functional characterization of these strains revealed that 41 of 84 strains had a minimum of three plant beneficial properties. Inoculation of maize seedlings with Acinetobacter spp., Microbacterium spp., Pectobacterium spp., Pseudomonas spp., and Enterobacter spp. showed positive effects on seedling biomass production. The ability of Brachiaria grasses to host genetically diverse bacteria, many of them with multiple plant growth-promoting attributes, might have contributed to high biomass production and adaptation of Brachiaria grasses to drought and low fertility soils.
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Affiliation(s)
- Collins Mutai
- Biosciences eastern and central Africa-International Livestock Research Institute (BecA-ILRI) Hub, Nairobi, Kenya
| | - Joyce Njuguna
- Biosciences eastern and central Africa-International Livestock Research Institute (BecA-ILRI) Hub, Nairobi, Kenya
| | - Sita Ghimire
- Biosciences eastern and central Africa-International Livestock Research Institute (BecA-ILRI) Hub, Nairobi, Kenya
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26
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Micalizzi EW, Mack JN, White GP, Avis TJ, Smith ML. Microbial inhibitors of the fungus Pseudogymnoascus destructans, the causal agent of white-nose syndrome in bats. PLoS One 2017. [PMID: 28632782 PMCID: PMC5478148 DOI: 10.1371/journal.pone.0179770] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
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.
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Affiliation(s)
- Emma W. Micalizzi
- Department of Biology, Carleton University, Ottawa, Ontario, Canada
- * E-mail:
| | - Jonathan N. Mack
- Department of Biology, Carleton University, Ottawa, Ontario, Canada
| | | | - Tyler J. Avis
- Department of Chemistry, Carleton University, Ottawa, Ontario, Canada
| | - Myron L. Smith
- Department of Biology, Carleton University, Ottawa, Ontario, Canada
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27
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Maslo B, Gignoux-Wolfsohn SA, Fefferman NH. Success of Wildlife Disease Treatment Depends on Host Immune Response. Front Ecol Evol 2017. [DOI: 10.3389/fevo.2017.00028] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
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28
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Padhi S, Dias I, Bennett JW. Two volatile-phase alcohols inhibit growth of Pseudogymnoascus destructans, causative agent of white-nose syndrome in bats. Mycology 2016. [DOI: 10.1080/21501203.2016.1269843] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
Affiliation(s)
- Sally Padhi
- Department of Plant Biology and Pathology, Rutgers University, New Brunswick, NJ, USA
| | - Itamar Dias
- Department of Plant Biology and Pathology, Rutgers University, New Brunswick, NJ, USA
| | - Joan W. Bennett
- Department of Plant Biology and Pathology, Rutgers University, New Brunswick, NJ, USA
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29
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Zhang T, Chaturvedi V, Chaturvedi S. Novel Trichoderma polysporum Strain for the Biocontrol of Pseudogymnoascus destructans, the Fungal Etiologic Agent of Bat White Nose Syndrome. PLoS One 2015; 10:e0141316. [PMID: 26509269 PMCID: PMC4624962 DOI: 10.1371/journal.pone.0141316] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2014] [Accepted: 10/07/2015] [Indexed: 01/01/2023] Open
Abstract
White-nose syndrome (WNS), an emerging disease of hibernating bats, has rapidly spread across eastern North America killing millions of bats. Pseudogymnoascus destructans (Pd), the sole etiologic agent of WNS, is widespread and persistent in bat hibernacula. Control of Pd in the affected sites is urgently needed to break the transmission cycle while minimizing any adverse impact on the native organisms. We isolated a novel strain of Trichoderma polysporum (Tp) from one of the caves at the epicenter of WNS zoonotic. Detailed experimental studies revealed: (1) Tp WPM 39143 was highly adapted to grow at temperatures simulating the cave environment (6°C-15°C), (2) Tp WPM 39143 restricted Pd colony growth in dual culture challenges, (3) Tp WPM 39143 caused four logs reduction of Pd colony forming units and genome copies in autoclaved soil samples from one of the WNS affected caves, (4) Tp WPM 39143 extract showed specific fungicidal activity against Pd in disk diffusion assay, but not against closely related fungus P. pannorum (Pp), (5) Tp WPM 39143 extract retained inhibitory activity after exposure to high temperatures, light and proteinase K, and (6) Inhibitory metabolites in Tp WPM 39143 extract comprised of water-soluble, high polarity compounds. These results suggest that Tp WPM 39143 is a promising candidate for further evaluation as a biocontrol agent of Pd in WNS affected sites.
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Affiliation(s)
- Tao Zhang
- Mycology Laboratory, Wadsworth Center, New York State Department of Health, Albany, New York, United States of America
| | - Vishnu Chaturvedi
- Mycology Laboratory, Wadsworth Center, New York State Department of Health, Albany, New York, United States of America
- Department of Biomedical Sciences, School of Public Health, University at Albany, Albany, New York, United States of America
| | - Sudha Chaturvedi
- Mycology Laboratory, Wadsworth Center, New York State Department of Health, Albany, New York, United States of America
- Department of Biomedical Sciences, School of Public Health, University at Albany, Albany, New York, United States of America
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30
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Maslo B, Valent M, Gumbs JF, Frick WF. Conservation implications of ameliorating survival of little brown bats with white-nose syndrome. ECOLOGICAL APPLICATIONS : A PUBLICATION OF THE ECOLOGICAL SOCIETY OF AMERICA 2015; 25:1832-40. [PMID: 26591449 DOI: 10.1890/14-2472.1] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Management of wildlife populations impacted by novel threats is often challenged by a lack of data on temporal changes in demographic response. Populations may suffer rapid declines from the introduction of new stressors, but how demography changes over time is critical to determining long-term outcomes for populations. White-nose syndrome (WNS), an infectious disease of hibernating bats, has caused massive and rapid population declines in several hibernating species of bats in North America since the disease was first observed on the continent in 2006. Estimating annual survival rates and demographic trends among remnant colonies of hibernating bats that experienced mass mortality from WNS is needed to determine long-term population viability of species impacted by this disease. Using mark-recapture data on infected little brown bats (Myotis lucifugus), we estimated the first apparent annual survival rates for four years following WNS detection at a site. We found strong support for an increasing trend in annual survival, which improved from 0.68 (95% CI = 0.44-0.85) to 0.75 (95% CI = 0.51-0.89) for males and 0.65 (95% CI = 0.44-0.81) to 0.70 (95% CI = 0.50-0.84) for females. These results suggest that stabilization at remnant colonies after mass mortality from WNS may be due to improved survival and not from immigration from other areas. Despite ameliorating survival, our stochastic matrix projection model predicts continued declines for little brown bat populations (λ = 0.95), raising concern for the regional persistence of this species. We conducted a vital rate sensitivity analysis and determined that adult and juvenile survival, as opposed to fecundity, are the demographic parameters most important to target to maximize recovery potential of little brown bat populations in areas impacted by WNS.
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31
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Willis CKR. Conservation Physiology and Conservation Pathogens: White-Nose Syndrome and Integrative Biology for Host-Pathogen Systems. Integr Comp Biol 2015; 55:631-41. [PMID: 26307096 DOI: 10.1093/icb/icv099] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
Conservation physiology aims to apply an understanding of physiological mechanisms to management of imperiled species, populations, or ecosystems. One challenge for physiologists hoping to apply their expertise to conservation is connecting the mechanisms we study, often in the laboratory, with the vital rates of populations in the wild. There is growing appreciation that infectious pathogens can threaten populations and species, and represent an important issue for conservation. Conservation physiology has much to offer in terms of addressing the threat posed to some host species by infectious pathogens. At the same time, the well-developed theoretical framework of disease ecology could provide a model to help advance the application of physiology to a range of other conservation issues. Here, I use white-nose syndrome (WNS) in hibernating North American bats as an example of a conservation problem for which integrative physiological research has been a critical part of research and management. The response to WNS highlights the importance of a well-developed theoretical framework for the application of conservation physiology to a particular threat. I review what is known about physiological mechanisms associated with mortality from WNS and emphasize the value of combining a strong theoretical background with integrative physiological studies in order to connect physiological mechanisms with population processes and thereby maximize the potential benefits of conservation physiology.
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Affiliation(s)
- Craig K R Willis
- Department of Biology and Centre for Forest Inter-disciplinary Research, University of Winnipeg, 515 Portage Avenue, Winnipeg, Manitoba Canada R3B2E9
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32
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Maslo B, Fefferman NH. A case study of bats and white-nose syndrome demonstrating how to model population viability with evolutionary effects. CONSERVATION BIOLOGY : THE JOURNAL OF THE SOCIETY FOR CONSERVATION BIOLOGY 2015; 29:1176-1185. [PMID: 25808080 DOI: 10.1111/cobi.12485] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/16/2014] [Accepted: 12/17/2014] [Indexed: 06/04/2023]
Abstract
Ecological factors generally affect population viability on rapid time scales. Traditional population viability analyses (PVA) therefore focus on alleviating ecological pressures, discounting potential evolutionary impacts on individual phenotypes. Recent studies of evolutionary rescue (ER) focus on cases in which severe, environmentally induced population bottlenecks trigger a rapid evolutionary response that can potentially reverse demographic threats. ER models have focused on shifting genetics and resulting population recovery, but no one has explored how to incorporate those findings into PVA. We integrated ER into PVA to identify the critical decision interval for evolutionary rescue (DIER) under which targeted conservation action should be applied to buffer populations undergoing ER against extinction from stochastic events and to determine the most appropriate vital rate to target to promote population recovery. We applied this model to little brown bats (Myotis lucifugus) affected by white-nose syndrome (WNS), a fungal disease causing massive declines in several North American bat populations. Under the ER scenario, the model predicted that the DIER period for little brown bats was within 11 years of initial WNS emergence, after which they stabilized at a positive growth rate (λ = 1.05). By comparing our model results with population trajectories of multiple infected hibernacula across the WNS range, we concluded that ER is a potential explanation of observed little brown bat population trajectories across multiple hibernacula within the affected range. Our approach provides a tool that can be used by all managers to provide testable hypotheses regarding the occurrence of ER in declining populations, suggest empirical studies to better parameterize the population genetics and conservation-relevant vital rates, and identify the DIER period during which management strategies will be most effective for species conservation.
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Affiliation(s)
- Brooke Maslo
- Department of Ecology, Evolution and Natural Resources, Rutgers, The State University of New Jersey, 14 College Farm Road, New Brunswick, NJ, 08901, U.S.A
- Rutgers Cooperative Extension, New Jersey Agricultural Experiment Station, Rutgers, The State University of New Jersey, 88 Lipman Drive, New Brunswick, NJ, 08901, U.S.A
| | - Nina H Fefferman
- Department of Ecology, Evolution and Natural Resources, Rutgers, The State University of New Jersey, 14 College Farm Road, New Brunswick, NJ, 08901, U.S.A
- The Center for Discrete Mathematics and Theoretical Computer Science (DIMACS), Rutgers, The State University of New Jersey, 96 Frelinghuysen Road, Piscataway, NJ, 08854, U.S.A
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Effect of Trans, Trans-Farnesol on Pseudogymnoascus destructans and Several Closely Related Species. Mycopathologia 2015; 180:325-32. [PMID: 26162644 DOI: 10.1007/s11046-015-9921-2] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2015] [Accepted: 06/30/2015] [Indexed: 12/20/2022]
Abstract
Bat white-nose syndrome, caused by the psychrophilic fungus Pseudogymnoascus destructans, has dramatically reduced the populations of many hibernating North American bat species. The search for effective biological control agents targeting P. destructans is of great importance. We report that the sesquiterpene trans, trans-farnesol, which is also a Candida albicans quorum sensing compound, prevented in vitro conidial germination for at least 14 days and inhibited growth of preexisting hyphae of five P. destructans isolates in filtered potato dextrose broth at 10 °C. Depending on the inoculation concentrations, both spore and hyphal inhibition occurred upon exposure to concentrations as low as 15-20 µM trans, trans-farnesol. In contrast, most North American Pseudogymnoascus isolates were more tolerant to the exposure of trans, trans-farnesol. Our results suggest that some Candida isolates may have the potential to inhibit the growth of P. destructans and that the sesquiterpene trans, trans-farnesol has the potential to be utilized as a biological control agent.
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Hoyt JR, Cheng TL, Langwig KE, Hee MM, Frick WF, Kilpatrick AM. Bacteria isolated from bats inhibit the growth of Pseudogymnoascus destructans, the causative agent of white-nose syndrome. PLoS One 2015; 10:e0121329. [PMID: 25853558 PMCID: PMC4390377 DOI: 10.1371/journal.pone.0121329] [Citation(s) in RCA: 102] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2014] [Accepted: 01/30/2015] [Indexed: 12/16/2022] Open
Abstract
Emerging infectious diseases are a key threat to wildlife. Several fungal skin pathogens have recently emerged and caused widespread mortality in several vertebrate groups, including amphibians, bats, rattlesnakes and humans. White-nose syndrome, caused by the fungal skin pathogen Pseudogymnoascus destructans, threatens several hibernating bat species with extinction and there are few effective treatment strategies. The skin microbiome is increasingly understood to play a large role in determining disease outcome. We isolated bacteria from the skin of four bat species, and co-cultured these isolates with P. destructans to identify bacteria that might inhibit or kill P. destructans. We then conducted two reciprocal challenge experiments in vitro with six bacterial isolates (all in the genus Pseudomonas) to quantify the effect of these bacteria on the growth of P. destructans. All six Pseudomonas isolates significantly inhibited growth of P. destructans compared to non-inhibitory control bacteria, and two isolates performed significantly better than others in suppressing P. destructans growth for at least 35 days. In both challenge experiments, the extent of suppression of P. destructans growth was dependent on the initial concentration of P. destructans and the initial concentration of the bacterial isolate. These results show that bacteria found naturally occurring on bats can inhibit the growth of P. destructans in vitro and should be studied further as a possible probiotic to protect bats from white-nose syndrome. In addition, the presence of these bacteria may influence disease outcomes among individuals, populations, and species.
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Affiliation(s)
- Joseph R. Hoyt
- Department of Ecology and Evolutionary Biology, University of California Santa Cruz, Santa Cruz, California, United States of America
- * E-mail:
| | - Tina L. Cheng
- Department of Ecology and Evolutionary Biology, University of California Santa Cruz, Santa Cruz, California, United States of America
| | - Kate E. Langwig
- Department of Ecology and Evolutionary Biology, University of California Santa Cruz, Santa Cruz, California, United States of America
| | - Mallory M. Hee
- Department of Ecology and Evolutionary Biology, University of California Santa Cruz, Santa Cruz, California, United States of America
| | - Winifred F. Frick
- Department of Ecology and Evolutionary Biology, University of California Santa Cruz, Santa Cruz, California, United States of America
| | - A. Marm Kilpatrick
- Department of Ecology and Evolutionary Biology, University of California Santa Cruz, Santa Cruz, California, United States of America
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