1
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Martínez-Ugalde E, Ávila-Akerberg V, González Martínez TM, Rebollar EA. Gene functions of the Ambystoma altamirani skin microbiome vary across space and time but potential antifungal genes are widespread and prevalent. Microb Genom 2024; 10:001181. [PMID: 38240649 PMCID: PMC10868611 DOI: 10.1099/mgen.0.001181] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2023] [Accepted: 01/02/2024] [Indexed: 01/23/2024] Open
Abstract
Amphibian skin microbiomes can play a critical role in host survival against emerging diseases by protecting their host against pathogens. While a plethora of biotic and abiotic factors have been shown to influence the taxonomic diversity of amphibian skin microbiomes it remains unclear whether functional genomic diversity varies in response to temporal and environmental factors. Here we applied a metagenomic approach to evaluate whether seasonality, distinct elevations/sites, and pathogen presence influenced the functional genomic diversity of the A. altamirani skin microbiome. We obtained a gene catalogue of 92 107 nonredundant annotated genes and a set of 50 unique metagenome assembled genomes (MAGs). Our analysis showed that genes linked to general and potential antifungal traits significantly differed across seasons and sampling locations at different elevations. Moreover, we found that the functional genomic diversity of A. altamirani skin microbiome differed between B. dendrobatidis infected and not infected axolotls only during winter, suggesting an interaction between seasonality and pathogen infection. In addition, we identified the presence of genes and biosynthetic gene clusters (BGCs) linked to potential antifungal functions such as biofilm formation, quorum sensing, secretion systems, secondary metabolite biosynthesis, and chitin degradation. Interestingly genes linked to these potential antifungal traits were mainly identified in Burkholderiales and Chitinophagales MAGs. Overall, our results identified functional traits linked to potential antifungal functions in the A. altamirani skin microbiome regardless of variation in the functional diversity across seasons, elevations/sites, and pathogen presence. Our findings suggest that potential antifungal traits found in Burkholderiales and Chitinophagales taxa could be related to the capacity of A. altamirani to survive in the presence of Bd, although further experimental analyses are required to test this hypothesis.
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Affiliation(s)
| | - Víctor Ávila-Akerberg
- Instituto de Ciencias Agropecuarias y Rurales, Universidad Autónoma del Estado de México, Toluca, Mexico
| | | | - Eria A. Rebollar
- Centro de Ciencias Genómicas, Universidad Nacional Autónoma de México, Cuernavaca, Mexico
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2
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Campos PM, Lucid MK, Ehlers S, Walke JB. Low-level pathogen infection and geographic location correlate with the skin microbiomes of Columbia spotted frogs ( Rana luteiventris) in a montane landscape. CURRENT RESEARCH IN MICROBIAL SCIENCES 2023; 6:100213. [PMID: 38187998 PMCID: PMC10770434 DOI: 10.1016/j.crmicr.2023.100213] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2024] Open
Abstract
The skin microbiome of amphibians can influence host susceptibility towards the fungal pathogen Batrachochytrium dendrobatidis (Bd), while simultaneously having the potential to be altered by Bd. Severe Bd infections are known to alter the amphibian skin microbiome; however, little is known about microbiome interactions in amphibians with low infection intensity. In addition to disease dynamics, environmental factors may influence the microbiome. To test for patterns in bacterial diversity based on pathogen infection and environmental factors, 399 Columbia spotted frogs (Rana luteiventris) were sampled throughout northern Idaho and northeastern Washington across two years. Bd prevalence and intensity were measured in 376 frogs, revealing a prevalence of 69%, but generally low infection intensity (Mean = 127 Bd zoospore equivalents among infected frogs). Skin bacterial communities were characterized in 92 frogs using 16S rRNA gene amplicon sequencing. Our results indicated correlations of decreasing Shannon diversity and evenness as infection intensity increased. Latitude was correlated with bacterial richness and Faith's Phylogenetic Diversity measures, indicating increased diversity in northern locations. Beta diversity (UniFrac) analyses revealed that skin microbiomes were distinct between infected and uninfected frogs, and infection intensity had a significant effect on microbiome composition. Site explained the majority of microbiome variation (weighted UniFrac: 57.5%), suggesting a combination of local habitat conditions explain variation, as only small proportions of variation could be explained by year, month, temperature, elevation, and latitude individually. Bacterial genera with potential for Bd-inhibitory properties were found with differential relative abundance in infected and uninfected frogs, with higher Stenotrophomonas and lower Pseudomonas relative abundance observed in infected frogs. Further study may indicate if Bd inhibition by members of the skin microbiome is an influence behind the low infection intensities observed and whether low Bd infection intensities are capable of altering skin microbiome composition.
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Affiliation(s)
- Philip M. Campos
- Department of Biology, Eastern Washington University, 1175 Washington St., Cheney, WA 99004, USA
| | - Michael K. Lucid
- Idaho Department of Fish and Game, 2885 Kathleen Ave., Coeur d'Alene, ID 83815, USA
- Selkirk Wildlife Science, LLC, PO Box 733, Sandpoint, ID 83864, USA
| | - Shannon Ehlers
- Idaho Department of Fish and Game, 2885 Kathleen Ave., Coeur d'Alene, ID 83815, USA
- U.S. Fish and Wildlife Service, 287 Westside Rd., Bonners Ferry, ID 83805, USA
| | - Jenifer B. Walke
- Department of Biology, Eastern Washington University, 1175 Washington St., Cheney, WA 99004, USA
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3
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Tytar V, Nekrasova O, Pupins M, Skute A, Kirjušina M, Gravele E, Mezaraupe L, Marushchak O, Čeirāns A, Kozynenko I, Kulikova AA. Modeling the Distribution of the Chytrid Fungus Batrachochytrium dendrobatidis with Special Reference to Ukraine. J Fungi (Basel) 2023; 9:607. [PMID: 37367543 DOI: 10.3390/jof9060607] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2023] [Revised: 05/21/2023] [Accepted: 05/22/2023] [Indexed: 06/28/2023] Open
Abstract
Amphibians are the most threatened group of vertebrates. While habitat loss poses the greatest threat to amphibians, a spreading fungal disease caused by Batrachochytrium dendrobatidis Longcore, Pessier & D.K. Nichols 1999 (Bd) is seriously affecting an increasing number of species. Although Bd is widely prevalent, there are identifiable heterogeneities in the pathogen's distribution that are linked to environmental parameters. Our objective was to identify conditions that affect the geographic distribution of this pathogen using species distribution models (SDMs) with a special focus on Eastern Europe. SDMs can help identify hotspots for future outbreaks of Bd but perhaps more importantly identify locations that may be environmental refuges ("coldspots") from infection. In general, climate is considered a major factor driving amphibian disease dynamics, but temperature in particular has received increased attention. Here, 42 environmental raster layers containing data on climate, soil, and human impact were used. The mean annual temperature range (or 'continentality') was found to have the strongest constraint on the geographic distribution of this pathogen. The modeling allowed to distinguish presumable locations that may be environmental refuges from infection and set up a framework to guide future search (sampling) of chytridiomycosis in Eastern Europe.
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Affiliation(s)
- Volodymyr Tytar
- I.I. Schmalhausen Institute of Zoology, National Academy of Sciences of Ukraine, 01030 Kyiv, Ukraine
| | - Oksana Nekrasova
- I.I. Schmalhausen Institute of Zoology, National Academy of Sciences of Ukraine, 01030 Kyiv, Ukraine
- Department of Ecology, Institute of Life Sciences and Technologies, Daugavpils University, LV5400 Daugavpils, Latvia
| | - Mihails Pupins
- Department of Ecology, Institute of Life Sciences and Technologies, Daugavpils University, LV5400 Daugavpils, Latvia
| | - Arturs Skute
- Department of Ecology, Institute of Life Sciences and Technologies, Daugavpils University, LV5400 Daugavpils, Latvia
| | - Muza Kirjušina
- Department of Ecology, Institute of Life Sciences and Technologies, Daugavpils University, LV5400 Daugavpils, Latvia
| | - Evita Gravele
- Department of Ecology, Institute of Life Sciences and Technologies, Daugavpils University, LV5400 Daugavpils, Latvia
| | - Ligita Mezaraupe
- Department of Ecology, Institute of Life Sciences and Technologies, Daugavpils University, LV5400 Daugavpils, Latvia
| | - Oleksii Marushchak
- I.I. Schmalhausen Institute of Zoology, National Academy of Sciences of Ukraine, 01030 Kyiv, Ukraine
| | - Andris Čeirāns
- Department of Ecology, Institute of Life Sciences and Technologies, Daugavpils University, LV5400 Daugavpils, Latvia
| | - Iryna Kozynenko
- I.I. Schmalhausen Institute of Zoology, National Academy of Sciences of Ukraine, 01030 Kyiv, Ukraine
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4
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Goodwin KB, Hutchinson JD, Gompert Z. Spatiotemporal and ontogenetic variation, microbial selection, and predicted Bd-inhibitory function in the skin-associated microbiome of a Rocky Mountain amphibian. Front Microbiol 2022; 13:1020329. [PMID: 36583053 PMCID: PMC9792605 DOI: 10.3389/fmicb.2022.1020329] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2022] [Accepted: 11/22/2022] [Indexed: 12/15/2022] Open
Abstract
Host-associated microbiomes play important roles in host health and pathogen defense. In amphibians, the skin-associated microbiota can contribute to innate immunity with potential implications for disease management. Few studies have examined season-long temporal variation in the amphibian skin-associated microbiome, and the interactions between bacteria and fungi on amphibian skin remain poorly understood. We characterize season-long temporal variation in the skin-associated microbiome of the western tiger salamander (Ambystoma mavortium) for both bacteria and fungi between sites and across salamander life stages. Two hundred seven skin-associated microbiome samples were collected from salamanders at two Rocky Mountain lakes throughout the summer and fall of 2018, and 127 additional microbiome samples were collected from lake water and lake substrate. We used 16S rRNA and ITS amplicon sequencing with Bayesian Dirichlet-multinomial regression to estimate the relative abundances of bacterial and fungal taxa, test for differential abundance, examine microbial selection, and derive alpha diversity. We predicted the ability of bacterial communities to inhibit the amphibian chytrid fungus Batrachochytrium dendrobatidis (Bd), a cutaneous fungal pathogen, using stochastic character mapping and a database of Bd-inhibitory bacterial isolates. For both bacteria and fungi, we observed variation in community composition through time, between sites, and with salamander age and life stage. We further found that temporal trends in community composition were specific to each combination of salamander age, life stage, and lake. We found salamander skin to be selective for microbes, with many taxa disproportionately represented relative to the environment. Salamander skin appeared to select for predicted Bd-inhibitory bacteria, and we found a negative relationship between the relative abundances of predicted Bd-inhibitory bacteria and Bd. We hope these findings will assist in the conservation of amphibian species threatened by chytridiomycosis and other emerging diseases.
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Affiliation(s)
- Kenen B. Goodwin
- Department of Watershed Sciences, Utah State University, Logan, UT, United States
- Department of Wildland Resources, Utah State University, Logan, UT, United States
| | - Jaren D. Hutchinson
- Department of Wildland Resources, Utah State University, Logan, UT, United States
| | - Zachariah Gompert
- Department of Biology, Utah State University, Logan, UT, United States
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5
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Martínez-Ugalde E, Ávila-Akerberg V, González Martínez TM, Vázquez Trejo M, Zavala Hernández D, Anaya-Morales SL, Rebollar EA. The skin microbiota of the axolotl Ambystoma altamirani is highly influenced by metamorphosis and seasonality but not by pathogen infection. Anim Microbiome 2022; 4:63. [PMID: 36503640 PMCID: PMC9743558 DOI: 10.1186/s42523-022-00215-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2022] [Accepted: 10/16/2022] [Indexed: 12/14/2022] Open
Abstract
BACKGROUND Microbiomes have been increasingly recognized as major contributors to host health and survival. In amphibians, bacterial members of the skin microbiota protect their hosts by inhibiting the growth of the fungal pathogen Batrachochytrium dendrobatidis (Bd). Even though several studies describe the influence of biotic and abiotic factors over the skin microbiota, it remains unclear how these symbiotic bacterial communities vary across time and development. This is particularly relevant for species that undergo metamorphosis as it has been shown that host physiology and ecology drastically influence diversity of the skin microbiome. RESULTS We found that the skin bacterial communities of the axolotl A. altamirani are largely influenced by the metamorphic status of the host and by seasonal variation of abiotic factors such as temperature, pH, dissolved oxygen and conductivity. Despite high Bd prevalence in these samples, the bacterial diversity of the skin microbiota did not differ between infected and non-infected axolotls, although relative abundance of particular bacteria were correlated with Bd infection intensity. CONCLUSIONS Our work shows that metamorphosis is a crucial process that shapes skin bacterial communities and that axolotls under different developmental stages respond differently to environmental seasonal variations. Moreover, this study greatly contributes to a better understanding of the factors that shape amphibian skin microbiota, especially in a largely underexplored group like axolotls (Mexican Ambystoma species).
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Affiliation(s)
| | - Víctor Ávila-Akerberg
- Instituto de Ciencias Agropecuarias y Rurales, Universidad Autónoma del Estado de México, Toluca, Mexico
| | | | | | | | - Sara Lucia Anaya-Morales
- Centro de Ciencias Genómicas, Universidad Nacional Autónoma de México, Cuernavaca, Mexico
- Department of Biology, University of Mississippi, Oxford, MS, USA
| | - Eria A Rebollar
- Centro de Ciencias Genómicas, Universidad Nacional Autónoma de México, Cuernavaca, Mexico.
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6
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Basanta MD, Anaya‐Morales SL, Martínez‐Ugalde E, González Martínez TM, Ávila‐Akerberg VD, Trejo MV, Rebollar EA. Metamorphosis and seasonality are major determinants of chytrid infection in a paedomorphic salamander. Anim Conserv 2022. [DOI: 10.1111/acv.12824] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- M. D. Basanta
- Centro de Ciencias Genómicas Universidad Nacional Autónoma de México Cuernavaca Morelos Mexico
- Department of Biology University of Nevada Reno Reno NV USA
| | - S. L. Anaya‐Morales
- Centro de Ciencias Genómicas Universidad Nacional Autónoma de México Cuernavaca Morelos Mexico
| | - E. Martínez‐Ugalde
- Centro de Ciencias Genómicas Universidad Nacional Autónoma de México Cuernavaca Morelos Mexico
| | - T. M. González Martínez
- Facultad de Ciencias Universidad Nacional Autónoma de México, Ciudad Universitaria Ciudad de México Mexico
| | - V. D. Ávila‐Akerberg
- Instituto de Ciencias Agropecuarias y Rurales Universidad Autónoma del Estado de México Toluca Estado de México Mexico
| | - M. V. Trejo
- Facultad de Ciencias Universidad Nacional Autónoma de México, Ciudad Universitaria Ciudad de México Mexico
| | - E. A. Rebollar
- Centro de Ciencias Genómicas Universidad Nacional Autónoma de México Cuernavaca Morelos Mexico
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7
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Abstract
Temporal changes and transmission patterns in host-associated microbial communities have important implications for host health. The diversity of amphibian skin microbial communities is associated with disease outcome in amphibians exposed to the fungal pathogen Batrachochytrium dendrobatidis (Bd). To successfully develop conservation strategies against Bd, we need a comprehensive understanding of how skin microbes are maintained and transmitted over time within populations. We used 16S rRNA sequence analysis to compare Epipedobates anthonyi frogs housed with one conspecific to frogs housed singly at four time points over the course of 1 year. We found that both α and β diversity of frog skin bacterial communities changed significantly over the course of the experiment. Specifically, we found that bacterial communities of cohabitating frogs became more similar over time. We also observed that some bacterial taxa were differentially abundant between frogs housed singly and frogs housed with a conspecific. These results suggest that conspecific contact may play a role in mediating amphibian skin microbial diversity and that turnover of skin microbial communities can occur across time. Our findings provide rationale for future studies exploring horizontal transmission as a potential mechanism of host-associated microbial maintenance in amphibians.
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Affiliation(s)
- Ariel Kruger
- Department of Ecology, Evolution, and Natural Resources, Rutgers University, New Brunswick, NJ, USA
| | - Spencer Roth
- Department of Environmental Sciences, Rutgers University, New Brunswick, NJ, USA.,Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, USA
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8
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Weitzman CL, Rostama B, Thomason CA, May M, Belden LK, Hawley DM. Experimental test of microbiome protection across pathogen doses reveals importance of resident microbiome composition. FEMS Microbiol Ecol 2021; 97:6385755. [PMID: 34626186 DOI: 10.1093/femsec/fiab141] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2021] [Accepted: 10/07/2021] [Indexed: 01/04/2023] Open
Abstract
The commensal microbes inhabiting a host tissue can interact with invading pathogens and host physiology in ways that alter pathogen growth and disease manifestation. Prior work in house finches (Haemorhous mexicanus) found that resident ocular microbiomes were protective against conjunctival infection and disease caused by a relatively high dose of Mycoplasma gallisepticum. Here, we used wild-caught house finches to experimentally examine whether protective effects of the resident ocular microbiome vary with the dose of invading pathogen. We hypothesized that commensal protection would be strongest at low M. gallisepticum inoculation doses because the resident microbiome would be less disrupted by invading pathogen. Our five M. gallisepticum dose treatments were fully factorial with an antibiotic treatment to perturb resident microbes just prior to M. gallisepticum inoculation. Unexpectedly, we found no indication of protective effects of the resident microbiome at any pathogen inoculation dose, which was inconsistent with the prior work. The ocular bacterial communities at the beginning of our experiment differed significantly from those previously reported in local wild-caught house finches, likely causing this discrepancy. These variable results underscore that microbiome-based protection in natural systems can be context dependent, and natural variation in community composition may alter the function of resident microbiomes in free-living animals.
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Affiliation(s)
- Chava L Weitzman
- Department of Biological Sciences, Virginia Tech, Blacksburg, VA 24060, USA
| | - Bahman Rostama
- Department of Biomedical Sciences, University of New England, Biddeford - 04005, ME, USA
| | - Courtney A Thomason
- Department of Biological Sciences, Virginia Tech, Blacksburg, VA 24060, USA.,Division of Remediation, Tennessee Department of Environment and Conservation, Oak Ridge - 37830, TN, USA
| | - Meghan May
- Department of Biomedical Sciences, University of New England, Biddeford - 04005, ME, USA
| | - Lisa K Belden
- Department of Biological Sciences, Virginia Tech, Blacksburg, VA 24060, USA
| | - Dana M Hawley
- Department of Biological Sciences, Virginia Tech, Blacksburg, VA 24060, USA
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9
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Li A, Li Z, Dai W, Parise KL, Leng H, Jin L, Liu S, Sun K, Hoyt JR, Feng J. Bacterial community dynamics on bats and the implications for pathogen resistance. Environ Microbiol 2021; 24:1484-1498. [PMID: 34472188 DOI: 10.1111/1462-2920.15754] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2021] [Revised: 07/07/2021] [Accepted: 08/30/2021] [Indexed: 02/02/2023]
Abstract
The bats skin microbiota plays an important role in reducing pathogen infection, including the deadly fungal pathogen Pseudogymnoascus destructans, the causative agent of white-nose syndrome. However, the dynamic of skin bacterial communities response to environmental perturbations remains poorly described. We characterized skin bacterial community over time and space in Rhinolophus ferrumequinum, a species with high resistance to the infection with P. destructans. We collected environmental covariate data to determine what factors influenced changes in community structure. We observed significant temporal and spatial shifts in the skin bacterial community, which was mainly associated with variation in operational taxonomic units. The skin bacterial community differed by the environmental microbial reservoirs and was most influenced by host body condition, bat roosting temperature and geographic distance between sites, but was not influenced by pathogen infection. Furthermore, the skin microbiota was enriched in particular taxa with antifungal abilities, such as Enterococcus, Burkholderia, Flavobacterium, Pseudomonas, Corynebacterium and Rhodococcus. And specific strains of Pseudomonas, Corynebacterium and Rhodococcus even inhibited P. destructans growth. Our findings provide new insights in characterizing the variation in bacterial communities can inform us about the processes of driving community assembly and predict the host's ability to resist or survive pathogen infection.
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Affiliation(s)
- Aoqiang Li
- Jilin Provincial Key Laboratory of Animal Resource Conservation and Utilization, Northeast Normal University, 2555 Jingyue Street, Changchun, 130117, China.,Key Laboratory of Vegetation Ecology, Ministry of Education, Changchun, 130024, China
| | - Zhongle Li
- Jilin Provincial Key Laboratory of Animal Resource Conservation and Utilization, Northeast Normal University, 2555 Jingyue Street, Changchun, 130117, China.,College of Animal Science and Technology, Jilin Agricultural University, Changchun, 130118, China
| | - Wentao Dai
- Jilin Provincial Key Laboratory of Animal Resource Conservation and Utilization, Northeast Normal University, 2555 Jingyue Street, Changchun, 130117, China
| | - Katy L Parise
- Pathogen and Microbiome Institute, Northern Arizona University, Flagstaff, AZ, 86011, USA
| | - Haixia Leng
- Jilin Provincial Key Laboratory of Animal Resource Conservation and Utilization, Northeast Normal University, 2555 Jingyue Street, Changchun, 130117, China
| | - Longru Jin
- Jilin Provincial Key Laboratory of Animal Resource Conservation and Utilization, Northeast Normal University, 2555 Jingyue Street, Changchun, 130117, China
| | - Sen Liu
- College of Life Sciences, Henan Normal University, Xinxiang, 453007, China
| | - Keping Sun
- Jilin Provincial Key Laboratory of Animal Resource Conservation and Utilization, Northeast Normal University, 2555 Jingyue Street, Changchun, 130117, China
| | - Joseph R Hoyt
- Department of Biological Sciences, Virginia Polytechnic Institute, Blacksburg, VA, 24060, USA
| | - Jiang Feng
- Jilin Provincial Key Laboratory of Animal Resource Conservation and Utilization, Northeast Normal University, 2555 Jingyue Street, Changchun, 130117, China.,College of Life Science, Jilin Agricultural University, Changchun, 130118, China
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10
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Ellison S, Knapp R, Vredenburg V. Longitudinal patterns in the skin microbiome of wild, individually marked frogs from the Sierra Nevada, California. ISME COMMUNICATIONS 2021; 1:45. [PMID: 37938625 PMCID: PMC9723788 DOI: 10.1038/s43705-021-00047-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/13/2021] [Revised: 08/04/2021] [Accepted: 08/17/2021] [Indexed: 05/29/2023]
Abstract
The amphibian skin microbiome has been the focus of numerous studies because of the protective effects that some bacteria provide against the pathogenic fungus Batrachochytrium dendrobatidis, which has caused a global panzootic among amphibians. However, the mechanisms driving community structure and function in the amphibian skin microbiome are still poorly understood, and longitudinal analyses of the skin microbiome have not yet been conducted in wild populations. In this study, we investigate longitudinal patterns in the skin microbiome of 19 individually marked adult frogs from two wild populations of the endangered Sierra Nevada yellow-legged frog (Rana sierrae), sampled over the course of 2 years. We found that individuals with low bacterial diversity (dominated by order Burkhorderiales) had significantly more stable bacterial communities than those with higher diversity. Amplicon sequence variants (ASVs) with high relative abundance were significantly less transient than those with low relative abundance, and ASVs with intermediate-level relative abundances experienced the greatest volatility over time. Based on these results, we suggest that efforts to develop probiotic treatments to combat B. dendrobatidis should focus on bacteria that are found at high relative abundances in some members of a population, as these strains are more likely to persist and remain stable in the long term.
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Affiliation(s)
- Silas Ellison
- Department of Biology, San Francisco State University, San Francisco, California, USA.
| | - Roland Knapp
- Sierra Nevada Aquatic Research Laboratory, University of California, Mammoth Lakes, CA, USA
| | - Vance Vredenburg
- Department of Biology, San Francisco State University, San Francisco, California, USA
- Museum of Vertebrate Zoology, University of California, Berkeley, California, USA
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11
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Barnes EM, Kutos S, Naghshineh N, Mesko M, You Q, Lewis JD. Assembly of the amphibian microbiome is influenced by the effects of land-use change on environmental reservoirs. Environ Microbiol 2021; 23:4595-4611. [PMID: 34190389 DOI: 10.1111/1462-2920.15653] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2021] [Revised: 06/15/2021] [Accepted: 06/28/2021] [Indexed: 01/04/2023]
Abstract
A growing focus in microbial ecology is understanding how beneficial microbiome function is created and maintained through various assembly mechanisms. This study explores the role of both the environment and disease in regulating the composition of microbial species in the soil and on amphibian hosts. We compared the microbial communities of Plethodon cinereus salamanders along a land-use gradient in the New York metropolitan area and paired these with associated soil cores. Additionally, we characterized the diversity of bacterial and fungal symbionts that putatively inhibit the pathogenic fungus Batrachochytrium dendrobatidis. We predicted that variation in skin microbial community composition would correlate with changes seen in the soil which functions as the regional species pool. We found that salamanders and soil share many microbial taxa but that these two communities exhibit differences in the relative abundances of the bacterial phyla Acidobacteria, Actinobacteria, and Proteobacteria and the fungal phyla Ascomycota and genus Basidiobolus. Microbial community composition varies with changes in land-use associated factors creating site-specific compositions. By employing a quantitative, null-based assembly model, we identified that dispersal limitation, variable selection, and drift guide assembly of microbes onto their skin, creating high dissimilarity between individuals with likely consequences in disease preventative function.
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Affiliation(s)
- Elle M Barnes
- Louis Calder Center - Biological Field Station, Fordham University, Armonk, NY, 10504, USA.,Department of Biological Sciences, Fordham University, Bronx, NY, 10458, USA
| | - Steve Kutos
- Louis Calder Center - Biological Field Station, Fordham University, Armonk, NY, 10504, USA.,Department of Biological Sciences, Fordham University, Bronx, NY, 10458, USA
| | - Nina Naghshineh
- Louis Calder Center - Biological Field Station, Fordham University, Armonk, NY, 10504, USA.,Department of Biological Sciences, Fordham University, Bronx, NY, 10458, USA
| | - Marissa Mesko
- Department of Biological Sciences, Fordham University, Bronx, NY, 10458, USA
| | - Qing You
- Department of Biological Sciences, Fordham University, Bronx, NY, 10458, USA
| | - J D Lewis
- Louis Calder Center - Biological Field Station, Fordham University, Armonk, NY, 10504, USA.,Department of Biological Sciences, Fordham University, Bronx, NY, 10458, USA
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12
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Walke JB, Becker MH, Krinos A, Chang EAB, Santiago C, Umile TP, Minbiole KPC, Belden LK. Seasonal changes and the unexpected impact of environmental disturbance on skin bacteria of individual amphibians in a natural habitat. FEMS Microbiol Ecol 2021; 97:6024676. [PMID: 33278302 DOI: 10.1093/femsec/fiaa248] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2020] [Accepted: 12/02/2020] [Indexed: 01/16/2023] Open
Abstract
Amphibians host diverse skin bacteria that have a role in pathogen defense, but these skin communities could change over time and impact this function. Here, we monitored individual Eastern red-spotted newts (Notophthalmus viridescens; N = 17) for 2 years in a field pond enclosure and assessed the effects of season and disturbance on skin bacterial community dynamics. We created disturbances by adding additional pond substrate to the enclosure at two timepoints. We planned to sample the skin bacterial community and metabolite profiles of each newt every 6 weeks; we ultimately sampled eight individuals at least six times. We used 16S rRNA gene amplicon sequencing to characterize the bacterial communities and HPLC-MS for metabolite profiling. We found that disturbance had a dramatic effect on skin bacterial communities and metabolite profiles, while season had an effect only using select metrics. There were seven core bacterial taxa (97% OTUs) that were found on all newts in all seasons, pre- and post-disturbance. Lastly, there was a correlation between bacterial and metabolite profiles post-disturbance, which was not observed pre-disturbance. This longitudinal study suggests that environmental disturbances can have lasting effects on skin bacterial communities that overwhelm seasonal changes, although the core bacteria remain relatively consistent over time.
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Affiliation(s)
- Jenifer B Walke
- Department of Biological Sciences, Virginia Tech, Blacksburg, VA 24061, USA
| | - Matthew H Becker
- Department of Biological Sciences, Virginia Tech, Blacksburg, VA 24061, USA
| | - Arianna Krinos
- Department of Biological Sciences, Virginia Tech, Blacksburg, VA 24061, USA
| | | | - Celina Santiago
- Department of Chemistry, Villanova University, Villanova, PA 19085, USA
| | - Thomas P Umile
- Department of Chemistry, Villanova University, Villanova, PA 19085, USA
| | | | - Lisa K Belden
- Department of Biological Sciences, Virginia Tech, Blacksburg, VA 24061, USA
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13
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Ruthsatz K, Lyra ML, Lambertini C, Belasen AM, Jenkinson TS, da Silva Leite D, Becker CG, Haddad CFB, James TY, Zamudio KR, Toledo LF, Vences M. Skin microbiome correlates with bioclimate and Batrachochytrium dendrobatidis infection intensity in Brazil's Atlantic Forest treefrogs. Sci Rep 2020; 10:22311. [PMID: 33339839 PMCID: PMC7749163 DOI: 10.1038/s41598-020-79130-3] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2020] [Accepted: 12/04/2020] [Indexed: 12/20/2022] Open
Abstract
In Brazil’s Atlantic Forest (AF) biodiversity conservation is of key importance since the fungal pathogen Batrachochytrium dendrobatidis (Bd) has led to the rapid loss of amphibian populations here and worldwide. The impact of Bd on amphibians is determined by the host's immune system, of which the skin microbiome is a critical component. The richness and diversity of such cutaneous bacterial communities are known to be shaped by abiotic factors which thus may indirectly modulate host susceptibility to Bd. This study aimed to contribute to understanding the environment-host–pathogen interaction determining skin bacterial communities in 819 treefrogs (Anura: Hylidae and Phyllomedusidae) from 71 species sampled across the AF. We investigated whether abiotic factors influence the bacterial community richness and structure on the amphibian skin. We further tested for an association between skin bacterial community structure and Bd co-occurrence. Our data revealed that temperature, precipitation, and elevation consistently correlate with richness and diversity of the skin microbiome and also predict Bd infection status. Surprisingly, our data suggest a weak but significant positive correlation of Bd infection intensity and bacterial richness. We highlight the prospect of future experimental studies on the impact of changing environmental conditions associated with global change on environment-host–pathogen interactions in the AF.
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Affiliation(s)
- Katharina Ruthsatz
- Institute of Zoology, Universität Hamburg, Martin-Luther-King-Platz 3, 20146, Hamburg, Germany. .,Zoological Institute, Technische Universität Braunschweig, Mendelssohnstraße 4, 38106, Brunswick, Germany.
| | - Mariana L Lyra
- Laboratório de Herpetologia, Depto de Biodiversidade, Instituto de Biociências and Centro de Aquicultura (CAUNESP), Universidade Estadual Paulista - UNESP, Rio Claro, São Paulo, Brazil
| | - Carolina Lambertini
- Laboratório de História Natural de Anfíbios Brasileiros (LaHNAB), Departamento de Biologia Animal, Instituto de Biologia, Universidade Estadual de Campinas, Campinas, São Paulo, 13083-862, Brazil
| | - Anat M Belasen
- Department of Ecology and Evolutionary Biology, Cornell University, Ithaca, NY, 14853-2701, USA
| | - Thomas S Jenkinson
- Department of Wildlife, Fish and Conservation Biology, University of California, Davis, Davis, CA, USA
| | - Domingos da Silva Leite
- Laboratório de Antígenos Bacterianos II, Departamento de Genética, Evolução, Microbiologia e Imunologia, Instituto de Biologia, Universidade Estadual de Campinas, Caixa Postal 6109, Campinas, São Paulo, CEP 13083-862, Brazil
| | - C Guilherme Becker
- Department of Biological Sciences, The University of Alabama, Tuscaloosa, AL, 35847, USA
| | - Célio F B Haddad
- Laboratório de Herpetologia, Depto de Biodiversidade, Instituto de Biociências and Centro de Aquicultura (CAUNESP), Universidade Estadual Paulista - UNESP, Rio Claro, São Paulo, Brazil
| | - Timothy Y James
- Department of Ecology and Evolutionary Biology, University of Michigan, Ann Arbor, MI, 48109, USA
| | - Kelly R Zamudio
- Department of Ecology and Evolutionary Biology, Cornell University, Ithaca, NY, 14853-2701, USA
| | - Luís Felipe Toledo
- Laboratório de História Natural de Anfíbios Brasileiros (LaHNAB), Departamento de Biologia Animal, Instituto de Biologia, Universidade Estadual de Campinas, Campinas, São Paulo, 13083-862, Brazil
| | - Miguel Vences
- Zoological Institute, Technische Universität Braunschweig, Mendelssohnstraße 4, 38106, Brunswick, Germany
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14
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Eleftheriou A. Relationships among host microbiota, parasite resistance or tolerance, and host fitness. CONSERVATION BIOLOGY : THE JOURNAL OF THE SOCIETY FOR CONSERVATION BIOLOGY 2020; 34:1327-1328. [PMID: 32652576 DOI: 10.1111/cobi.13582] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/06/2020] [Revised: 06/22/2020] [Accepted: 06/26/2020] [Indexed: 06/11/2023]
Abstract
Article impact statement: Parasite-induced shifts in host microbiota that lead to parasite resistance or tolerance may have unintended consequences for host fitness.
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Affiliation(s)
- Andreas Eleftheriou
- Wildlife Biology Program, University of Montana, 32 Campus Drive, FOR 109, Missoula, MT, 59812, U.S.A
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15
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Rebollar EA, Martínez-Ugalde E, Orta AH. The Amphibian Skin Microbiome and Its Protective Role Against Chytridiomycosis. HERPETOLOGICA 2020. [DOI: 10.1655/0018-0831-76.2.167] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Affiliation(s)
- Eria A. Rebollar
- Centro de Ciencias Genómicas, Universidad Nacional Autónoma de México, Cuernavaca, Morelos 62210, México
| | - Emanuel Martínez-Ugalde
- Centro de Ciencias Genómicas, Universidad Nacional Autónoma de México, Cuernavaca, Morelos 62210, México
| | - Alberto H. Orta
- Centro de Ciencias Genómicas, Universidad Nacional Autónoma de México, Cuernavaca, Morelos 62210, México
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16
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Solak HM, Yanchukov A, Çolak F, Matur F, Sözen M, Ayanoğlu İC, Winternitz JC. Altitudinal Effects on Innate Immune Response of a Subterranean Rodent. Zoolog Sci 2020; 37:31-41. [PMID: 32068372 DOI: 10.2108/zs190067] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2019] [Accepted: 08/27/2019] [Indexed: 11/17/2022]
Abstract
Immune defense is costly to maintain and deploy, and the optimal investment into immune defense depends on risk of infection. Altitude is a natural environmental factor that is predicted to affect parasite abundance, with lower parasite abundance predicted at higher altitudes due to stronger environmental stressors, which reduce parasite transmission. Using high and low altitude populations of the Turkish blind mole-rat (TBMR) Nannospalax xanthodon, we tested for effects of altitude on constitutive innate immune defense. Field studies were performed with 32 wild animals in 2017 and 2018 from two low- and one high-altitude localities in the Central Taurus Mountains, at respective altitudes of 1010 m, 1115 m, and 2900 m above sea level. We first compared innate standing immune defense as measured by the bacteria-killing ability of blood serum. We then measured corticosterone stress hormone levels, as stressful conditions may affect immune response. Finally, we compared prevalence and intensity of gastrointestinal parasites of field-captured TBMR. We found that the bacteria-killing ability of serum is greater in the mole-rat samples from high altitude. There was no significant difference in stress (corticosterone) levels between altitude categories. Coccidian prevalence and abundance were significantly higher in 2017 than 2018 samples, but there was no significant difference in prevalence, abundance, or intensity between altitudes, or between sexes. Small sample sizes may have reduced power to detect true differences; nevertheless, this study provides support that greater standing innate immunity in high altitude animals may reflect greater investment into constitutive defense.
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Affiliation(s)
- Halil Mert Solak
- Department of Biology, Faculty of Arts and Science, Bülent Ecevit University, Farabi Campus, 67100, İncivez, Zonguldak, Turkey
| | - Alexey Yanchukov
- Department of Biology, Faculty of Arts and Science, Bülent Ecevit University, Farabi Campus, 67100, İncivez, Zonguldak, Turkey
| | - Faruk Çolak
- Department of Biology, Faculty of Arts and Science, Bülent Ecevit University, Farabi Campus, 67100, İncivez, Zonguldak, Turkey
| | - Ferhat Matur
- Department of Biology, Faculty of Science, Dokuz Eylül University, Tınaztepe Campus, 35390, Buca, İzmir, Turkey
| | - Mustafa Sözen
- Department of Biology, Faculty of Arts and Science, Bülent Ecevit University, Farabi Campus, 67100, İncivez, Zonguldak, Turkey
| | - İhsan Cihan Ayanoğlu
- Department of Biological Sciences, Faculty of Arts and Science, Middle East Technical University, 06800 Çankaya, Ankara, Turkey
| | - Jamie C Winternitz
- Department of Animal Behavior, Bielefeld University, Morgenbreede 45, 33615 Bielefeld, Germany,
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17
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Barnes EM, Carter EL, Lewis JD. Predicting Microbiome Function Across Space Is Confounded by Strain-Level Differences and Functional Redundancy Across Taxa. Front Microbiol 2020; 11:101. [PMID: 32117131 PMCID: PMC7018939 DOI: 10.3389/fmicb.2020.00101] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2019] [Accepted: 01/17/2020] [Indexed: 12/30/2022] Open
Abstract
Variation in the microbiome among individual organisms may play a critical role in the relative susceptibility of those organisms to infection, disease, and death. However, predicting microbiome function is difficult because of spatial and temporal variation in microbial diversity, and taxonomic diversity is not predictive of microbiome functional diversity. Addressing this issue may be particularly important when addressing pandemic diseases, such as the global amphibian die-off associated with Bd. Some of the most important factors in probiotic development for disease treatment are whether bacteria with desired function can be found on native amphibians in the local environment. To address this issue, we isolated, sequenced, and assayed the cutaneous bacterial communities of Plethodon cinereus along a gradient of land use change. Our results suggest that cutaneous community composition, but not overall diversity, change with changes in land use, but this does not correspond to significant change in Bd-inhibitory function. We found that Bd-inhibition is a functionally redundant trait, but that level of inhibition varies over phylogenetic, spatial, and temporal scales. This research provides further evidence for the importance of continued examination of amphibian microbial communities across environmental gradients, including biotic and abiotic interactions, when considering disease dynamics.
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Affiliation(s)
- Elle M Barnes
- Department of Biological Sciences, Louis Calder Center - Biological Field Station, Fordham University, Armonk, NY, United States.,Department of Biological Sciences and Center for Urban Ecology, Fordham University, Bronx, NY, United States
| | - Erin L Carter
- Department of Biological Sciences and Center for Urban Ecology, Fordham University, Bronx, NY, United States
| | - J D Lewis
- Department of Biological Sciences, Louis Calder Center - Biological Field Station, Fordham University, Armonk, NY, United States.,Department of Biological Sciences and Center for Urban Ecology, Fordham University, Bronx, NY, United States
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18
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Therkorn J, Drewry D, Andonian J, Benishek L, Billman C, Forsyth ER, Garibaldi BT, Nowakowski E, Rainwater-Lovett K, Sauer L, Schiffhauer M, Maragakis LL. Development and Comparison of Complementary Methods to Study Potential Skin and Inhalational Exposure to Pathogens During Personal Protective Equipment Doffing. Clin Infect Dis 2019; 69:S231-S240. [PMID: 31517983 PMCID: PMC6761368 DOI: 10.1093/cid/ciz616] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
BACKGROUND Fluorescent tracers are often used with ultraviolet lights to visibly identify healthcare worker self-contamination after doffing of personal protective equipment (PPE). This method has drawbacks, as it cannot detect pathogen-sized contaminants nor airborne contamination in subjects' breathing zones. METHODS A contamination detection/quantification method was developed using 2-µm polystyrene latex spheres (PSLs) to investigate skin contamination (via swabbing) and potential inhalational exposure (via breathing zone air sampler). Porcine skin coupons were used to estimate the PSL swabbing recovery efficiency and limit of detection (LOD). A pilot study with 5 participants compared skin contamination levels detected via the PSL vs fluorescent tracer methods, while the air sampler quantified potential inhalational exposure to PSLs during doffing. RESULTS Average PSL skin swab recovery efficiency was 40% ± 29% (LOD = 1 PSL/4 cm2 of skin). In the pilot study, all subjects had PSL and fluorescent tracer skin contamination. Two subjects had simultaneously located contamination of both types on a wrist and hand. However, for all other subjects, the PSL method enabled detection of skin contamination that was not detectable by the fluorescent tracer method. Hands/wrists were more commonly contaminated than areas of the head/face (57% vs 23% of swabs with PSL detection, respectively). One subject had PSLs detected by the breathing zone air sampler. CONCLUSIONS This study provides a well-characterized method that can be used to quantitate levels of skin and inhalational contact with simulant pathogen particles. The PSL method serves as a complement to the fluorescent tracer method to study PPE doffing self-contamination.
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Affiliation(s)
- Jennifer Therkorn
- Applied Biological Sciences, Johns Hopkins Applied Physics Laboratory, Laurel
| | - David Drewry
- Applied Biological Sciences, Johns Hopkins Applied Physics Laboratory, Laurel
| | - Jennifer Andonian
- Department of Hospital Epidemiology and Infection Control, Johns Hopkins Health System, Baltimore, Maryland
| | - Lauren Benishek
- Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Carrie Billman
- Department of Hospital Epidemiology and Infection Control, Johns Hopkins Health System, Baltimore, Maryland
| | - Ellen R Forsyth
- Applied Biological Sciences, Johns Hopkins Applied Physics Laboratory, Laurel
| | | | - Elaine Nowakowski
- Department of Hospital Epidemiology and Infection Control, Johns Hopkins Health System, Baltimore, Maryland
| | | | - Lauren Sauer
- Johns Hopkins University School of Medicine, Baltimore, Maryland
- Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland
| | - Maggie Schiffhauer
- Department of Hospital Epidemiology and Infection Control, Johns Hopkins Health System, Baltimore, Maryland
| | - Lisa L Maragakis
- Department of Hospital Epidemiology and Infection Control, Johns Hopkins Health System, Baltimore, Maryland
- Johns Hopkins University School of Medicine, Baltimore, Maryland
- Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland
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19
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Jiménez RR, Alvarado G, Estrella J, Sommer S. Moving Beyond the Host: Unraveling the Skin Microbiome of Endangered Costa Rican Amphibians. Front Microbiol 2019; 10:2060. [PMID: 31572313 PMCID: PMC6751270 DOI: 10.3389/fmicb.2019.02060] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2019] [Accepted: 08/21/2019] [Indexed: 01/12/2023] Open
Abstract
Some neotropical amphibians, including a few species in Costa Rica, were presumed to be "extinct" after dramatic population declines in the late 1980s but have been rediscovered in isolated populations. Such populations seem to have evolved a resistance/tolerance to Batrachochytrium dendrobatidis (Bd), a fungal pathogen that causes a deadly skin disease and is considered one of the main drivers of worldwide amphibian declines. The skin microbiome is an important component of the host's innate immune system and is associated with Bd-resistance. However, the way that the bacterial diversity of the skin microbiome confers protection against Bd in surviving species remains unclear. We studied variation in the skin microbiome and the prevalence of putatively anti-Bd bacterial taxa in four co-habiting species in the highlands of the Juan Castro Blanco National Park in Costa Rica using 16S rRNA amplicon sequencing. Lithobates vibicarius, Craugastor escoces, and Isthmohyla rivularis have recently been rediscovered, whereas Isthmohyla pseudopuma has suffered population fluctuations but has never disappeared. To investigate the life stage at which the protective skin microbiome is shaped and when shifts occur in the diversity of putatively anti-Bd bacteria, we studied the skin microbiome of tadpoles, juveniles and adults of L. vibicarius. We show that the skin bacterial composition of sympatric species and hosts with distinct Bd-infection statuses differs at the phyla, family, and genus level. We detected 94 amplicon sequence variants (ASVs) with putative anti-Bd activity pertaining to distinct bacterial taxa, e.g., Pseudomonas spp., Acinetobacter johnsonii, and Stenotrophomonas maltophilia. Bd-uninfected L. vibicarius harbored 79% more putatively anti-Bd ASVs than Bd-infected individuals. Although microbiome composition and structure differed across life stages, the diversity of putative anti-Bd bacteria was similar between pre- and post-metamorphic stages of L. vibicarius. Despite low sample size, our results support the idea that the skin microbiome is dynamic and protects against ongoing Bd presence in endangered species persisting after their presumed extinction. Our study serves as a baseline to understand the microbial patterns in species of high conservation value. Identification of microbial signatures linked to variation in disease susceptibility might, therefore, inform mitigation strategies for combating the global decline of amphibians.
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Affiliation(s)
- Randall R. Jiménez
- Institute of Evolutionary Ecology and Conservation Genomics, University of Ulm, Ulm, Germany
| | - Gilbert Alvarado
- Laboratory of Comparative Wildlife Pathology, School of Veterinary Medicine and Animal Sciences, University of São Paulo, São Paulo, Brazil
- Laboratory of Experimental and Comparative Pathology (LAPECOM), Biology School, University of Costa Rica, San José, Costa Rica
| | - Josimar Estrella
- Laboratory of Experimental and Comparative Pathology (LAPECOM), Biology School, University of Costa Rica, San José, Costa Rica
| | - Simone Sommer
- Institute of Evolutionary Ecology and Conservation Genomics, University of Ulm, Ulm, Germany
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20
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Estrada A, Hughey MC, Medina D, Rebollar EA, Walke JB, Harris RN, Belden LK. Skin bacterial communities of neotropical treefrogs vary with local environmental conditions at the time of sampling. PeerJ 2019; 7:e7044. [PMID: 31275740 PMCID: PMC6590418 DOI: 10.7717/peerj.7044] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2018] [Accepted: 04/27/2019] [Indexed: 12/28/2022] Open
Abstract
The amphibian skin microbiome has been the focus of recent studies aiming to better understand the role of these microbial symbionts in host defense against disease. However, host-associated microbial communities are complex and dynamic, and changes in their composition and structure can influence their function. Understanding temporal variation of bacterial communities on amphibian skin is critical for establishing baselines from which to improve the development of mitigation techniques based on probiotic therapy and provides long-term host protection in a changing environment. Here, we investigated whether microbial communities on amphibian skin change over time at a single site. To examine this, we collected skin swabs from two pond-breeding species of treefrogs, Agalychnis callidryas and Dendropsophus ebraccatus, over 4 years at a single lowland tropical pond in Panamá. Relative abundance of operational taxonomic units (OTUs) based on 16S rRNA gene amplicon sequencing was used to determine bacterial community diversity on the skin of both treefrog species. We found significant variation in bacterial community structure across long and short-term time scales. Skin bacterial communities differed across years on both species and between seasons and sampling days only in D. ebraccatus. Importantly, bacterial community structures across days were as variable as year level comparisons. The differences in bacterial community were driven primarily by differences in relative abundance of key OTUs and explained by rainfall at the time of sampling. These findings suggest that skin-associated microbiomes are highly variable across time, and that for tropical lowland sites, rainfall is a good predictor of variability. However, more research is necessary to elucidate the significance of temporal variation in bacterial skin communities and their maintenance for amphibian conservation efforts.
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Affiliation(s)
- Angie Estrada
- Department of Biological Sciences, Virginia Polytechnic Institute and State University (Virginia Tech), Blacksburg, VA, USA
| | - Myra C Hughey
- Department of Biological Sciences, Virginia Polytechnic Institute and State University (Virginia Tech), Blacksburg, VA, USA
| | - Daniel Medina
- Department of Biological Sciences, Virginia Polytechnic Institute and State University (Virginia Tech), Blacksburg, VA, USA
| | - Eria A Rebollar
- Centro de Ciencias Genómicas, Universidad Nacional Autónoma de México, Cuernavaca, Morelos, México
| | - Jenifer B Walke
- Department of Biological Sciences, Virginia Polytechnic Institute and State University (Virginia Tech), Blacksburg, VA, USA
| | - Reid N Harris
- Department of Biology, James Madison University, Harrisonburg, VA, USA
| | - Lisa K Belden
- Department of Biological Sciences, Virginia Polytechnic Institute and State University (Virginia Tech), Blacksburg, VA, USA.,Smithsonian Tropical Research Institute, Balboa, Ancón, Panamá, Panamá
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21
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Bie J, Liu X, Zhang X, Wang H. Detection and comparative analysis of cutaneous bacterial communities of farmed and wild Rana dybowskii (Amphibia: Anura). THE EUROPEAN ZOOLOGICAL JOURNAL 2019. [DOI: 10.1080/24750263.2019.1683627] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022] Open
Affiliation(s)
- J. Bie
- Heilongjiang Key Laboratory for Laboratory Animals and Comparative Medicine, College of Veterinary Medicine, Northeast Agricultural University, Harbin, China
| | - X. Liu
- Heilongjiang Key Laboratory for Laboratory Animals and Comparative Medicine, College of Veterinary Medicine, Northeast Agricultural University, Harbin, China
| | - X. Zhang
- Heilongjiang Key Laboratory for Laboratory Animals and Comparative Medicine, College of Veterinary Medicine, Northeast Agricultural University, Harbin, China
| | - H. Wang
- Heilongjiang Key Laboratory for Laboratory Animals and Comparative Medicine, College of Veterinary Medicine, Northeast Agricultural University, Harbin, China
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22
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Bell SC, Garland S, Alford RA. Increased Numbers of Culturable Inhibitory Bacterial Taxa May Mitigate the Effects of Batrachochytrium dendrobatidis in Australian Wet Tropics Frogs. Front Microbiol 2018; 9:1604. [PMID: 30072970 PMCID: PMC6058028 DOI: 10.3389/fmicb.2018.01604] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2017] [Accepted: 06/27/2018] [Indexed: 11/20/2022] Open
Abstract
Symbiotic bacterial communities resident on amphibian skin can benefit their hosts. For example, antibiotic production by community members can control the pathogen Batrachochytrium dendrobatidis (Bd) and it is possible for these community members to be used as probiotics to reduce infection levels. In the early 1990s, the emergence of Bd caused declines and disappearances of frogs in the Australian Wet Tropics; the severity of its effects varied among species and sites. Some species have since recolonized despite enzootic Bd within their populations. This variation in history among species and sites provided an opportunity to investigate the role of anti-fungal cutaneous bacteria in protecting frogs against Bd infection. We collected cutaneous swab samples from three species of frogs at two upland and two lowland sites in the Wet Tropics, and used in vitro challenge assays to identify culturable Bd-inhibitory bacterial isolates for further analysis. We sequenced DNA from cultured inhibitory isolates to identify taxa, resulting in the classification of 16 Bd-inhibitory OTUs, and determined whether inhibitory taxa were associated with frog species, site, or intensity of infection. We present preliminary results showing that the upper limit of Bd infection intensity was negatively correlated with number of inhibitory OTUs present per frog indicating that increased numbers of Bd-inhibiting taxa may play a role in reducing the intensity of Bd infections, facilitating frog coexistence with enzootic Bd. One upland site had a significantly lower prevalence of Bd infection, a significantly higher proportion of frogs with one or more culturable Bd-inhibitory OTUs, a greater number of inhibitory bacterial genera present per frog, and statistically significant clustering of individual frogs with similar Bd-inhibitory signatures when compared to all other sites. This suggests that Bd-inhibitory taxa are likely to be particularly important to frogs at this site and may have played a role in their ability to recolonize following population declines. Our findings suggest that the use of multi-taxon Bd-inhibitory probiotics to support at-risk amphibian populations may be more effective than single-taxon alternatives.
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Affiliation(s)
- Sara C. Bell
- College of Science and Engineering, James Cook University, Townsville, QLD, Australia
| | - Stephen Garland
- College of Public Health, Medical and Veterinary Sciences, James Cook University, Townsville, QLD, Australia
| | - Ross A. Alford
- College of Science and Engineering, James Cook University, Townsville, QLD, Australia
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