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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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Strachinis I, Marschang RE, Lymberakis P, Karagianni KM, Azmanis P. Infectious disease threats to amphibians in Greece: new localities positive for Batrachochytrium dendrobatidis. DISEASES OF AQUATIC ORGANISMS 2022; 152:127-138. [PMID: 36519684 DOI: 10.3354/dao03712] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/17/2023]
Abstract
In the early 2000s, numerous cases of European amphibian population declines and mass die-offs started to emerge. Investigating those events led to the discovery that wild European amphibians were confronted with grave disease threats caused by introduced pathogens, namely the amphibian and the salamander chytrid fungi Batrachochytrium dendrobatidis (Bd) and B. salamandrivorans (Bsal) and ranaviruses. In Greece, Bd was previously documented among wild amphibian populations in 2 different locations and 3 different species. However, no disease-related mass declines or mortality events have been reported. In this work, we build upon previous findings with new, subsequently obtained data, resulting in a 225-sample dataset of 14 species from 17 different locations throughout Greece, in order to examine the occurrence status of all 3 pathogens responsible for emerging infectious diseases in European amphibians. No positive samples for Bsal or ranavirus were recorded in any location. We confirmed the presence of Bd in 4 more localities and in 4 more species, including 1 urodelan (Macedonian crested newt Triturus macedonicus) and 1 introduced anuran (American bullfrog Lithobates catesbeianus). All insular localities were negative for Bd, except for Crete, where Bd was identified in 2 different locations. Again, no mass declines or die-offs were recorded in any Bd-positive area or elsewhere. However, given the persistence of Bd across Greece over the past ~20 yr, monitoring efforts should continue, and ideally be further expanded.
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Affiliation(s)
- Ilias Strachinis
- Department of Genetics, Development and Molecular Biology, School of Biology, Faculty of Natural Sciences, Aristotle University of Thessaloniki, 54636, Greece
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Stupar M, Savković Ž, Breka K, Stamenković S, Krizmanić I, Vukojević J, Grbić ML. A Variety of Fungal Species on the Green Frogs' Skin (Pelophylax esculentus complex) in South Banat. MICROBIAL ECOLOGY 2022:10.1007/s00248-022-02135-0. [PMID: 36322177 DOI: 10.1007/s00248-022-02135-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/08/2022] [Accepted: 10/24/2022] [Indexed: 06/16/2023]
Abstract
In the last several decades, amphibian populations have been declining worldwide. Many factors have been linked to global amphibian decline, including habitat destruction, pollution, introduced species, global environmental changes, and emerging infectious diseases. Recent studies of amphibian skin infections were mainly focused on the presence of chytridiomycosis, neglecting other members of the frogs' skin communities. The diversity pattern of fungal dwellers on the skin of green frogs (Pelophylax esculentus complex) was investigated. A total of 100 adults were sampled from three localities in South Banat (northern Serbia) over three consecutive years and detected fungal dwellers were identified using light microscopy and ITS and BenA gene sequencing. Structures belonging to fungi and fungus-like organisms including a variety of spores and different mycelia types were documented in the biofilm formed on amphibian skin, and are classified into 10 groups. In total, 42 fungal isolates were identified to species, section, or genus level. The difference in mycobiota composition between sampling points (localities and green frog taxa) was documented. The highest number of fungal structures and isolates was recorded on the hybrid taxon P. esculentus and locality Stevanove ravnice. Parental species showed a markedly lower diversity than the hybrid taxon and were more similar in diversity patterns and were placed in the same homogenous group. The locality Stevanove ravnice exhibited more pronounced differences in diversity pattern than the other two localities and was placed in a distinct and separate homogenous group. Among the fungal isolates, the highest isolation frequency was documented for Alternaria alternata, Aspergillus sp. sect. Nigri, Epicoccum nigrum, Fusarium proliferatum, and Trichoderma atroviride. Among the documented species, dematiaceous fungi, causative agents of chromomycosis in amphibians, were also recorded in this research with high isolation frequency. Also, some rare fungal species such as Quambalaria cyanescens and Pseudoteniolina globosa are documented for the first time in this research as microbial inhabitants of amphibian skin.
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Affiliation(s)
- Miloš Stupar
- University of Belgrade, Faculty of Biology, Studentski Trg 16, 11000, Belgrade, Serbia.
| | - Željko Savković
- University of Belgrade, Faculty of Biology, Studentski Trg 16, 11000, Belgrade, Serbia
| | - Katarina Breka
- University of Belgrade, Faculty of Biology, Studentski Trg 16, 11000, Belgrade, Serbia
| | - Srđan Stamenković
- University of Belgrade, Faculty of Biology, Studentski Trg 16, 11000, Belgrade, Serbia
| | - Imre Krizmanić
- University of Belgrade, Faculty of Biology, Studentski Trg 16, 11000, Belgrade, Serbia
| | - Jelena Vukojević
- University of Belgrade, Faculty of Biology, Studentski Trg 16, 11000, Belgrade, Serbia
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Zhang L, Chen C, Zou W, Chen X, Zhou M, Ma C, Xi X, Chen T, Shaw C, Liu M, Wang L. Two novel bombesin-like neuropeptides from the skin secretion of Pelophylax kl. esculentus: Ex vivo pharmacological characterization on rat smooth muscle types. Front Mol Biosci 2022; 9:953974. [PMID: 36250016 PMCID: PMC9560764 DOI: 10.3389/fmolb.2022.953974] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2022] [Accepted: 09/07/2022] [Indexed: 11/13/2022] Open
Abstract
Mammalian bombesin-like neuropeptides (BLPs) play an important role in regulation of physiological and pathophysiological processes. Frog skin-derived BLPs, of smaller size and diverse lengths and sequences at their N-terminus, have attracted the attention of many researchers. However, these N-terminal variants and the receptors modulating their pharmacological actions are poorly studied and less understood. In this study, two BLPs, namely, [Asn3, Lys6, Thr10, Phe13]3–14-bombesin and [Asn3, Lys6, Phe13]3–14-bombesin with primary structures NLGKQWATGHFM and NLGKQWAVGHFM were isolated from the skin secretion of hybrid Pelophylax kl. esculentus. Both BLPs share a similar primary structure with only a single amino acid substitution at the eighth position (threonine to valine), while they have quite different myotropic potencies with EC50 values in the range of 22.64 ± 9.7 nM (N = 8) to 83.93 ± 46.9 nM (N = 8). The potency of [Asn3, Lys6, Thr10, Phe13]3–14-bombesin was approximately 3-fold higher than that of [Asn3, Lys6, Phe13]3–14-bombesin. Through the investigation of receptor selectivity using a canonical bombesin receptor antagonist, it was found that [Asn3, Lys6, Thr10, Phe13]3–14-bombesin and [Asn3, Lys6, Phe13]3–14-bombesin had an affinity to both BB1 and BB2 receptors. Their contractile functions are mainly modulated by both BB1 and BB2 receptors on rat urinary bladder and BB2 alone on rat uterus smooth muscle preparations. These data may provide new insights into the design of potent and selective ligands for bombesin receptors. Moreover, [Asn3, Lys6, Thr10, Phe13]3–14-bombesin and [Asn3, Lys6, Phe13]3–14-bombesin did not induce significant hemolysis and toxicity in normal human cells, suggesting that these two natural novel BLPs have great potential for development into new drug candidates.
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Affiliation(s)
- Luyao Zhang
- Key Laboratory of Livestock Infectious Diseases in Northeast China, Ministry of Education, College of Animal Science and Veterinary Medicine, Shenyang Agricultural University, Shenyang, China
- School of Pharmacy, Queen’s University Belfast, Belfast, United Kingdom
| | - Chen Chen
- Key Laboratory of Livestock Infectious Diseases in Northeast China, Ministry of Education, College of Animal Science and Veterinary Medicine, Shenyang Agricultural University, Shenyang, China
| | - Wanchen Zou
- School of Pharmacy, Queen’s University Belfast, Belfast, United Kingdom
| | - Xiaoling Chen
- School of Pharmacy, Queen’s University Belfast, Belfast, United Kingdom
| | - Mei Zhou
- School of Pharmacy, Queen’s University Belfast, Belfast, United Kingdom
| | - Chengbang Ma
- School of Pharmacy, Queen’s University Belfast, Belfast, United Kingdom
| | - Xinping Xi
- School of Pharmacy, Queen’s University Belfast, Belfast, United Kingdom
| | - Tianbao Chen
- School of Pharmacy, Queen’s University Belfast, Belfast, United Kingdom
| | - Chris Shaw
- School of Pharmacy, Queen’s University Belfast, Belfast, United Kingdom
| | - Mingchun Liu
- Key Laboratory of Livestock Infectious Diseases in Northeast China, Ministry of Education, College of Animal Science and Veterinary Medicine, Shenyang Agricultural University, Shenyang, China
- *Correspondence: Mingchun Liu, ; Lei Wang,
| | - Lei Wang
- School of Pharmacy, Queen’s University Belfast, Belfast, United Kingdom
- *Correspondence: Mingchun Liu, ; Lei Wang,
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Lin Y, Jiang Y, Zhao Z, Lu Y, Xi X, Ma C, Chen X, Zhou M, Chen T, Shaw C, Wang L. Discovery of a Novel Antimicrobial Peptide, Temporin-PKE, from the Skin Secretion of Pelophylax kl. esculentus, and Evaluation of Its Structure-Activity Relationships. Biomolecules 2022; 12:biom12060759. [PMID: 35740884 PMCID: PMC9221509 DOI: 10.3390/biom12060759] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2022] [Revised: 05/26/2022] [Accepted: 05/26/2022] [Indexed: 11/25/2022] Open
Abstract
Bacterial resistance against antibiotics has led to increasing numbers of treatment failures, and AMPs are widely accepted as becoming potential alternatives due to their advantages. Temporin-PKE is a novel peptide extracted from the skin secretion of Pelophylax kl. esculentus and it displays a strong activity against Gram-positive bacteria, with an extreme cytotoxicity. Incorporating positively charged residues and introducing D-amino acids were the two main strategies adopted for the modifications. The transformation of the chirality of Ile could reduce haemolytic activity, and an analogue with appropriate D-isoforms could maintain antimicrobial activity and stability. The substitution of hydrophobic residues could bring about more potent and broad-spectrum antimicrobial activities. The analogues with Lys were less harmful to the normal cells and their stabilities remained at similarly high levels compared to temporin-PKE. The optimal number of charges was three, and the replacement on the polar face was a better choice. Temporin-PKE-3K exerted dually efficient functions includingstrong antimicrobial and anticancer activity. This analogue showed a reduced possibility for inducing resistance in MRSA and Klebsiella pneumoniae, a rather strong antimicrobial activity in vivo, and it exhibited the highest therapeutic index such that temporin-PKE-3K has the potential to be developed as a clinical drug.
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Affiliation(s)
- Yaxian Lin
- School of Pharmacy, Queen’s University Belfast, 97 Lisburn Road, Belfast BT9 7BL, UK; (Y.L.); (Y.J.); (Z.Z.); (Y.L.); (X.X.); (C.M.); (M.Z.); (T.C.); (C.S.)
| | - Yangyang Jiang
- School of Pharmacy, Queen’s University Belfast, 97 Lisburn Road, Belfast BT9 7BL, UK; (Y.L.); (Y.J.); (Z.Z.); (Y.L.); (X.X.); (C.M.); (M.Z.); (T.C.); (C.S.)
| | - Ziwei Zhao
- School of Pharmacy, Queen’s University Belfast, 97 Lisburn Road, Belfast BT9 7BL, UK; (Y.L.); (Y.J.); (Z.Z.); (Y.L.); (X.X.); (C.M.); (M.Z.); (T.C.); (C.S.)
- School of Traditional Chinese Medicine, Beijing University of Chinese Medicine, Beijing 100029, China
| | - Yueyang Lu
- School of Pharmacy, Queen’s University Belfast, 97 Lisburn Road, Belfast BT9 7BL, UK; (Y.L.); (Y.J.); (Z.Z.); (Y.L.); (X.X.); (C.M.); (M.Z.); (T.C.); (C.S.)
| | - Xinping Xi
- School of Pharmacy, Queen’s University Belfast, 97 Lisburn Road, Belfast BT9 7BL, UK; (Y.L.); (Y.J.); (Z.Z.); (Y.L.); (X.X.); (C.M.); (M.Z.); (T.C.); (C.S.)
| | - Chengbang Ma
- School of Pharmacy, Queen’s University Belfast, 97 Lisburn Road, Belfast BT9 7BL, UK; (Y.L.); (Y.J.); (Z.Z.); (Y.L.); (X.X.); (C.M.); (M.Z.); (T.C.); (C.S.)
| | - Xiaoling Chen
- School of Pharmacy, Queen’s University Belfast, 97 Lisburn Road, Belfast BT9 7BL, UK; (Y.L.); (Y.J.); (Z.Z.); (Y.L.); (X.X.); (C.M.); (M.Z.); (T.C.); (C.S.)
- Correspondence: (X.C.); (L.W.)
| | - Mei Zhou
- School of Pharmacy, Queen’s University Belfast, 97 Lisburn Road, Belfast BT9 7BL, UK; (Y.L.); (Y.J.); (Z.Z.); (Y.L.); (X.X.); (C.M.); (M.Z.); (T.C.); (C.S.)
| | - Tianbao Chen
- School of Pharmacy, Queen’s University Belfast, 97 Lisburn Road, Belfast BT9 7BL, UK; (Y.L.); (Y.J.); (Z.Z.); (Y.L.); (X.X.); (C.M.); (M.Z.); (T.C.); (C.S.)
| | - Chris Shaw
- School of Pharmacy, Queen’s University Belfast, 97 Lisburn Road, Belfast BT9 7BL, UK; (Y.L.); (Y.J.); (Z.Z.); (Y.L.); (X.X.); (C.M.); (M.Z.); (T.C.); (C.S.)
| | - Lei Wang
- School of Pharmacy, Queen’s University Belfast, 97 Lisburn Road, Belfast BT9 7BL, UK; (Y.L.); (Y.J.); (Z.Z.); (Y.L.); (X.X.); (C.M.); (M.Z.); (T.C.); (C.S.)
- Correspondence: (X.C.); (L.W.)
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Palomar G, Jakóbik J, Bosch J, Kolenda K, Kaczmarski M, Jośko P, Roces-Díaz JV, Stachyra P, Thumsová B, Zieliński P, Pabijan M. Emerging infectious diseases of amphibians in Poland: distribution and environmental drivers. DISEASES OF AQUATIC ORGANISMS 2021; 147:1-12. [PMID: 34734569 DOI: 10.3354/dao03631] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Emerging infectious diseases are a threat to biodiversity and have taken a large toll on amphibian populations worldwide. The chytrid fungi Batrachochytrium dendrobatidis (Bd) and B. salamandrivorans (Bsal), and the iridovirus Ranavirus (Rv), are of concern as all have contributed to amphibian declines. In central and eastern Europe, their geographical and host distributions and main environmental drivers determining prevalence are poorly known. We screened over 1000 amphibians from natural and captive populations in Poland for the presence of Bd, Bsal and Rv. In wild amphibian populations, we found that Bd is widespread, present in 46 out of 115 sampled localities as well as 2 captive colonies, and relatively common with overall prevalence at 14.4% in 9 species. We found lower prevalence of Rv at 2.4%, present in 11 out of 92 sampling sites, with a taxonomic breadth of 8 different amphibian species. Bsal infection was not detected in any individuals. In natural populations, Pelophylax esculentus and Bombina variegata accounted for 75% of all Bd infections, suggesting a major role for these 2 species as pathogen reservoirs in Central European freshwater habitats. General linear models showed that climatic as well as landscape features are associated with Bd infection in Poland. We found that higher average annual temperature constrains Bd infection, while landscapes with numerous water bodies or artificial elements (a surrogate for urbanization) increase the chances of infection. Our results show that a combination of climatic and landscape variables may drive regional and local pathogen emergence.
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Affiliation(s)
- Gemma Palomar
- Institute of Environmental Sciences, Faculty of Biology, Jagiellonian University, Gronostajowa 7, 30-387 Kraków, Poland
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Grogan LF, Humphries JE, Robert J, Lanctôt CM, Nock CJ, Newell DA, McCallum HI. Immunological Aspects of Chytridiomycosis. J Fungi (Basel) 2020; 6:jof6040234. [PMID: 33086692 PMCID: PMC7712659 DOI: 10.3390/jof6040234] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2020] [Revised: 10/14/2020] [Accepted: 10/15/2020] [Indexed: 12/27/2022] Open
Abstract
Amphibians are currently the most threatened vertebrate class, with the disease chytridiomycosis being a major contributor to their global declines. Chytridiomycosis is a frequently fatal skin disease caused by the fungal pathogens Batrachochytrium dendrobatidis (Bd) and Batrachochytrium salamandrivorans (Bsal). The severity and extent of the impact of the infection caused by these pathogens across modern Amphibia are unprecedented in the history of vertebrate infectious diseases. The immune system of amphibians is thought to be largely similar to that of other jawed vertebrates, such as mammals. However, amphibian hosts are both ectothermic and water-dependent, which are characteristics favouring fungal proliferation. Although amphibians possess robust constitutive host defences, Bd/Bsal replicate within host cells once these defences have been breached. Intracellular fungal localisation may contribute to evasion of the induced innate immune response. Increasing evidence suggests that once the innate defences are surpassed, fungal virulence factors suppress the targeted adaptive immune responses whilst promoting an ineffectual inflammatory cascade, resulting in immunopathology and systemic metabolic disruption. Thus, although infections are contained within the integument, crucial homeostatic processes become compromised, leading to mortality. In this paper, we present an integrated synthesis of amphibian post-metamorphic immunological responses and the corresponding outcomes of infection with Bd, focusing on recent developments within the field and highlighting future directions.
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Affiliation(s)
- Laura F. Grogan
- Environmental Futures Research Institute and School of Environment and Science, Griffith University, Southport, QLD 4222, Australia;
- Forest Research Centre, School of Environment, Science and Engineering, Southern Cross University, Lismore, NSW 2480, Australia; (J.E.H.); (D.A.N.)
- Correspondence:
| | - Josephine E. Humphries
- Forest Research Centre, School of Environment, Science and Engineering, Southern Cross University, Lismore, NSW 2480, Australia; (J.E.H.); (D.A.N.)
| | - Jacques Robert
- University of Rochester Medical Center, Rochester, NY 14642, USA;
| | - Chantal M. Lanctôt
- Australian Rivers Institute, Griffith University, Southport, QLD 4222, Australia;
| | - Catherine J. Nock
- Southern Cross Plant Science, Southern Cross University, Lismore, NSW 2480, Australia;
| | - David A. Newell
- Forest Research Centre, School of Environment, Science and Engineering, Southern Cross University, Lismore, NSW 2480, Australia; (J.E.H.); (D.A.N.)
| | - Hamish I. McCallum
- Environmental Futures Research Institute and School of Environment and Science, Griffith University, Southport, QLD 4222, Australia;
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E GX, Chen LP, Zhou DK, Yang BG, Zhang JH, Zhao YJ, Hong QH, Ma YH, Chu MX, Zhang LP, Basang WD, Zhu YB, Han YG, Na RS, Zeng Y, Zhao ZQ, Huang YF, Han JL. Evolutionary relationship and population structure of domestic Bovidae animals based on MHC-linked and neutral autosomal microsatellite markers. Mol Immunol 2020; 124:83-90. [PMID: 32544655 DOI: 10.1016/j.molimm.2020.05.005] [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: 12/30/2019] [Revised: 04/21/2020] [Accepted: 05/07/2020] [Indexed: 11/26/2022]
Abstract
Major histocompatibility complex (MHC) genes are critical for disease resistance or susceptibility responsible for host-pathogen interactions determined mainly by extensive polymorphisms in the MHC genes. Here, we examined the diversity and phylogenetic pattern of MHC haplotypes reconstructed using three MHC-linked microsatellite markers in 55 populations of five Bovidae species and compared them with those based on neutral autosomal microsatellite markers (NAMs). Three-hundred-and-forty MHC haplotypes were identified in 1453 Bovidae individuals, suggesting significantly higher polymorphism and heterozygosity compared with those based on NAMs. The ambitious boundaries in population differentiation (phylogenetic network, pairwise FST and STRUCTURE analyses) within and between species assessed using the MHC haplotypes were different from those revealed by NAMs associated closely with speciation, geographical distribution, domestication and management histories. In addition, the mean FST was significantly correlated negatively with the number of observed alleles (NA), observed (HO) and expected (HE) heterozygosity and polymorphism information content (PIC) (P < 0.05) in the MHC haplotype dataset while there was no correction of the mean FST estimates (P> 0.05) between the MHC haplotype and NAMs datasets. Analysis of molecular variance (AMOVA) revealed a lower percentage of total variance (PTV) between species/groups based on the MHC-linked microsatellites than NAMs. Therefore, it was inferred that individuals within populations accumulated as many MHC variants as possible to increase their heterozygosity and thus the survival rate of their affiliated populations and species, which eventually reduced population differentiation and thereby complicated their classification and phylogenetic relationship inference. In summary, host-pathogen coevolution and heterozygote advantage, rather than demographic history, act as key driving forces shaping the MHC diversity within the populations and determining the interspecific MHC diversity.
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Affiliation(s)
- Guang-Xin E
- College of Animal Science and Technology, Chongqing Key Laboratory of Forage & Herbivores, Chongqing Engineering Research Centre for Herbivore Resource Protection and Utilization, Southwest University, Chongqing 400716, China
| | - Li-Peng Chen
- College of Animal Science and Technology, Chongqing Key Laboratory of Forage & Herbivores, Chongqing Engineering Research Centre for Herbivore Resource Protection and Utilization, Southwest University, Chongqing 400716, China
| | - Dong-Ke Zhou
- College of Animal Science and Technology, Chongqing Key Laboratory of Forage & Herbivores, Chongqing Engineering Research Centre for Herbivore Resource Protection and Utilization, Southwest University, Chongqing 400716, China
| | - Bai-Gao Yang
- College of Animal Science and Technology, Chongqing Key Laboratory of Forage & Herbivores, Chongqing Engineering Research Centre for Herbivore Resource Protection and Utilization, Southwest University, Chongqing 400716, China
| | - Jia-Hua Zhang
- College of Animal Science and Technology, Chongqing Key Laboratory of Forage & Herbivores, Chongqing Engineering Research Centre for Herbivore Resource Protection and Utilization, Southwest University, Chongqing 400716, China
| | - Yong-Ju Zhao
- College of Animal Science and Technology, Chongqing Key Laboratory of Forage & Herbivores, Chongqing Engineering Research Centre for Herbivore Resource Protection and Utilization, Southwest University, Chongqing 400716, China
| | - Qiong-Hua Hong
- Yunnan Animal Science and Veterinary Institute, Kunming 650224, China
| | - Yue-Hui Ma
- Institute of Animal Science, Chinese Academy of Agricultural Sciences (CAAS), Beijing 100193, China
| | - Ming-Xing Chu
- Institute of Animal Science, Chinese Academy of Agricultural Sciences (CAAS), Beijing 100193, China
| | - Lu-Pei Zhang
- Institute of Animal Science, Chinese Academy of Agricultural Sciences (CAAS), Beijing 100193, China
| | - Wang-Dui Basang
- State Key Laboratory of Barley and Yak Germplasm Resources and Genetic Improvement (Tibet Academy of Agricultural and Animal Husbandry Science (TAAAS)), Lhasa 850002, China
| | - Yan-Bin Zhu
- State Key Laboratory of Barley and Yak Germplasm Resources and Genetic Improvement (Tibet Academy of Agricultural and Animal Husbandry Science (TAAAS)), Lhasa 850002, China
| | - Yan-Guo Han
- College of Animal Science and Technology, Chongqing Key Laboratory of Forage & Herbivores, Chongqing Engineering Research Centre for Herbivore Resource Protection and Utilization, Southwest University, Chongqing 400716, China
| | - Ri-Su Na
- College of Animal Science and Technology, Chongqing Key Laboratory of Forage & Herbivores, Chongqing Engineering Research Centre for Herbivore Resource Protection and Utilization, Southwest University, Chongqing 400716, China
| | - Yan Zeng
- College of Animal Science and Technology, Chongqing Key Laboratory of Forage & Herbivores, Chongqing Engineering Research Centre for Herbivore Resource Protection and Utilization, Southwest University, Chongqing 400716, China
| | - Zhong-Quan Zhao
- College of Animal Science and Technology, Chongqing Key Laboratory of Forage & Herbivores, Chongqing Engineering Research Centre for Herbivore Resource Protection and Utilization, Southwest University, Chongqing 400716, China
| | - Yong-Fu Huang
- College of Animal Science and Technology, Chongqing Key Laboratory of Forage & Herbivores, Chongqing Engineering Research Centre for Herbivore Resource Protection and Utilization, Southwest University, Chongqing 400716, China.
| | - Jian-Lin Han
- CAAS-ILRI Joint Laboratory on Livestock and Forage Genetic Resources Institute of Animal Science, Chinese Academy of Agricultural Sciences (CAAS), Beijing 100193, China; Livestock Genetics Program, International Livestock Research Institute (ILRI), Nairobi 00100, Kenya.
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9
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Hybridization Facilitates Adaptive Evolution in Two Major Fungal Pathogens. Genes (Basel) 2020; 11:genes11010101. [PMID: 31963231 PMCID: PMC7017293 DOI: 10.3390/genes11010101] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2019] [Revised: 01/02/2020] [Accepted: 01/14/2020] [Indexed: 01/13/2023] Open
Abstract
Hybridization is increasingly recognized as an important force impacting adaptation and evolution in many lineages of fungi. During hybridization, divergent genomes and alleles are brought together into the same cell, potentiating adaptation by increasing genomic plasticity. Here, we review hybridization in fungi by focusing on two fungal pathogens of animals. Hybridization is common between the basidiomycete yeast species Cryptococcus neoformans × Cryptococcus deneoformans, and hybrid genotypes are frequently found in both environmental and clinical settings. The two species show 10-15% nucleotide divergence at the genome level, and their hybrids are highly heterozygous. Though largely sterile and unable to mate, these hybrids can propagate asexually and generate diverse genotypes by nondisjunction, aberrant meiosis, mitotic recombination, and gene conversion. Under stress conditions, the rate of such genetic changes can increase, leading to rapid adaptation. Conversely, in hybrids formed between lineages of the chytridiomycete frog pathogen Batrachochytrium dendrobatidis (Bd), the parental genotypes are considerably less diverged (0.2% divergent). Bd hybrids are formed from crosses between lineages that rarely undergo sex. A common theme in both species is that hybrids show genome plasticity via aneuploidy or loss of heterozygosity and leverage these mechanisms as a rapid way to generate genotypic/phenotypic diversity. Some hybrids show greater fitness and survival in both virulence and virulence-associated phenotypes than parental lineages under certain conditions. These studies showcase how experimentation in model species such as Cryptococcus can be a powerful tool in elucidating the genotypic and phenotypic consequences of hybridization.
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10
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Development of a Novel Mule Deer Genomic Assembly and Species-Diagnostic SNP Panel for Assessing Introgression in Mule Deer, White-Tailed Deer, and Their Interspecific Hybrids. G3-GENES GENOMES GENETICS 2019; 9:911-919. [PMID: 30670611 PMCID: PMC6404596 DOI: 10.1534/g3.118.200838] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Mule deer (Odocoileus hemionus) are endemic to a wide variety of habitats in western North America, many of which are shared in sympatry with their closely related sister-species white-tailed deer (Odocoileus virginianus), whom they hybridize with in wild populations. Although mule deer meet many ideal conditions for a molecular ecological research species, such as high abundance, ecological importance, and broad dispersal and gene flow, conservation genetic studies have been limited by a relative lack of existing genomic resources and inherent difficulties caused by introgression with white-tailed deer. Many molecular tools currently available for the study of cervids were designed using reference assemblies of divergent model species, specifically cattle (Bos taurus). Bovidae and Cervidae diverged approximately 28 million years ago, therefore, we sought to ameliorate the available resources by contributing the first mule deer whole genome sequence draft assembly with an average genome-wide read depth of 25X, using the white-tailed genome assembly (Ovir.te_1.0) as a reference. Comparing the two assemblies, we identified ∼33 million single nucleotide polymorphisms (SNPs) and insertion/deletion variants. We then verified fixed SNP differences between the two species and developed a 40-loci SNP assay capable of identifying pure mule deer, white-tailed deer, and interspecific hybrids. Assignment capacity of the panel, which was tested on simulated datasets, is reliable up to and including the third backcross hybrid generation. Identification of post-F1 hybrids will be necessary for hybrid zone population studies going forward, and the new mule deer assembly will be a valuable resource for genetic and comparative genomics studies.
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11
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Grogan LF, Robert J, Berger L, Skerratt LF, Scheele BC, Castley JG, Newell DA, McCallum HI. Review of the Amphibian Immune Response to Chytridiomycosis, and Future Directions. Front Immunol 2018; 9:2536. [PMID: 30473694 PMCID: PMC6237969 DOI: 10.3389/fimmu.2018.02536] [Citation(s) in RCA: 87] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2018] [Accepted: 10/15/2018] [Indexed: 12/27/2022] Open
Abstract
The fungal skin disease, chytridiomycosis (caused by Batrachochytrium dendrobatidis and B. salamandrivorans), has caused amphibian declines and extinctions globally since its emergence. Characterizing the host immune response to chytridiomycosis has been a focus of study with the aim of disease mitigation. However, many aspects of the innate and adaptive arms of this response are still poorly understood, likely due to the wide range of species' responses to infection. In this paper we provide an overview of expected immunological responses (with inference based on amphibian and mammalian immunology), together with a synthesis of current knowledge about these responses for the amphibian-chytridiomycosis system. We structure our review around four key immune stages: (1) the naïve immunocompetent state, (2) immune defenses that are always present (constitutive defenses), (3) mechanisms for recognition of a pathogen threat and innate immune defenses, and (4) adaptive immune responses. We also evaluate the current hot topics of immunosuppression and immunopathology in chytridiomycosis, and discuss their respective roles in pathogenesis. Our synthesis reveals that susceptibility to chytridiomycosis is likely to be multifactorial. Susceptible amphibians appear to have ineffective constitutive and innate defenses, and a late-stage response characterized by immunopathology and Bd-induced suppression of lymphocyte responses. Overall, we identify substantial gaps in current knowledge, particularly concerning the entire innate immune response (mechanisms of initial pathogen detection and possible immunoevasion by Bd, degree of activation and efficacy of the innate immune response, the unexpected absence of innate leukocyte infiltration, and the cause and role of late-stage immunopathology in pathogenesis). There are also gaps concerning most of the adaptive immune system (the relative importance of B and T cell responses for pathogen clearance, the capacity and extent of immunological memory, and specific mechanisms of pathogen-induced immunosuppression). Improving our capacity for amphibian immunological research will require selection of an appropriate Bd-susceptible model species, the development of taxon-specific affinity reagents and cell lines for functional assays, and the application of a suite of conventional and emerging immunological methods. Despite current knowledge gaps, immunological research remains a promising avenue for amphibian conservation management.
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Affiliation(s)
- Laura F Grogan
- Environmental Futures Research Institute and School of Environment and Science, Griffith University, Nathan, QLD, Australia
| | - Jacques Robert
- University of Rochester Medical Center, Rochester, NY, United States
| | - Lee Berger
- One Health Research Group, College of Public Health, Medical and Veterinary Sciences, James Cook University, Townsville, QLD, Australia.,Faculty of Veterinary and Agricultural Sciences, Melbourne Veterinary School, University of Melbourne, Werribee, VIC, Australia
| | - Lee F Skerratt
- One Health Research Group, College of Public Health, Medical and Veterinary Sciences, James Cook University, Townsville, QLD, Australia.,Faculty of Veterinary and Agricultural Sciences, Melbourne Veterinary School, University of Melbourne, Werribee, VIC, Australia
| | - Benjamin C Scheele
- Fenner School of Environment and Society, The Australian National University, Canberra, ACT, Australia.,Threatened Species Recovery Hub, National Environmental Science Program, Fenner School of Environment and Society, The Australian National University, Canberra, ACT, Australia
| | - J Guy Castley
- Environmental Futures Research Institute and School of Environment and Science, Griffith University, Nathan, QLD, Australia
| | - David A Newell
- Forest Research Centre, School of Environment, Science and Engineering, Southern Cross University, Lismore, NSW, Australia
| | - Hamish I McCallum
- Environmental Futures Research Institute and School of Environment and Science, Griffith University, Nathan, QLD, Australia
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12
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Flechas SV, Acosta-González A, Escobar LA, Kueneman JG, Sánchez-Quitian ZA, Parra-Giraldo CM, Rollins-Smith LA, Reinert LK, Vredenburg VT, Amézquita A, Woodhams DC. Microbiota and skin defense peptides may facilitate coexistence of two sympatric Andean frog species with a lethal pathogen. ISME JOURNAL 2018; 13:361-373. [PMID: 30254321 DOI: 10.1038/s41396-018-0284-9] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/07/2018] [Revised: 08/21/2018] [Accepted: 08/23/2018] [Indexed: 12/13/2022]
Abstract
Management of hyper-virulent generalist pathogens is an emergent global challenge, yet for most disease systems we lack a basic understanding as to why some host species suffer mass mortalities, while others resist epizootics. We studied two sympatric species of frogs from the Colombian Andes, which coexist with the amphibian pathogen Batrachochytrium dendrobatidis (Bd), to understand why some species did not succumb to the infection. We found high Bd prevalence in juveniles for both species, yet infection intensities remained low. We also found that bacterial community composition and host defense peptides are specific to amphibian life stages. We detected abundant Bd-inhibitory skin bacteria across life stages and Bd-inhibitory defense peptides post-metamorphosis in both species. Bd-inhibitory bacteria were proportionally more abundant in adults of both species than in earlier developmental stages. We tested for activity of peptides against the skin microbiota and found that in general peptides did not negatively affect bacterial growth and in some instances facilitated growth. Our results suggest that symbiotic bacteria and antimicrobial peptides may be co-selected for, and that together they contribute to the ability of Andean amphibian species to coexist with the global pandemic lineage of Bd.
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Affiliation(s)
- Sandra V Flechas
- Department of Biological Sciences, Universidad de los Andes, Bogotá, 111711, Colombia. .,Instituto de Investigación de Recursos Biológicos Alexander von Humboldt, Bogotá, Colombia.
| | | | - Laura A Escobar
- Department of Microbiology, Faculty of Sciences, Pontificia Universidad Javeriana, Bogotá, AA 56710, Colombia
| | - Jordan G Kueneman
- Biology Department, University of Massachusetts Boston, Boston, MA, 02125, USA.,Smithsonian Tropical Research Institute, Panama, Apartado 0843-03092, Republic of Panama
| | - Zilpa Adriana Sánchez-Quitian
- Department of Microbiology, Faculty of Sciences, Pontificia Universidad Javeriana, Bogotá, AA 56710, Colombia.,Environmental Management Group, Department of Biology and Microbiology, Universidad de Boyacá, Tunja, 150000003, Colombia
| | - Claudia M Parra-Giraldo
- Department of Microbiology, Faculty of Sciences, Pontificia Universidad Javeriana, Bogotá, AA 56710, Colombia
| | - Louise A Rollins-Smith
- Department of Pathology, Microbiology and Immunology, Vanderbilt University, School of Medicine, Nashville, TN, 37232, USA
| | - Laura K Reinert
- Department of Pathology, Microbiology and Immunology, Vanderbilt University, School of Medicine, Nashville, TN, 37232, USA
| | - Vance T Vredenburg
- Department of Biology, San Francisco State University, San Francisco, CA, 94132-1722, USA
| | - Adolfo Amézquita
- Department of Biological Sciences, Universidad de los Andes, Bogotá, 111711, Colombia
| | - Douglas C Woodhams
- Biology Department, University of Massachusetts Boston, Boston, MA, 02125, USA.,Smithsonian Tropical Research Institute, Panama, Apartado 0843-03092, Republic of Panama
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13
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Zohrab F, Askarian S, Jalili A, Kazemi Oskuee R. Biological Properties, Current Applications and Potential Therapeautic Applications of Brevinin Peptide Superfamily. Int J Pept Res Ther 2018; 25:39-48. [PMID: 32214928 PMCID: PMC7087712 DOI: 10.1007/s10989-018-9723-8] [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] [Accepted: 05/25/2018] [Indexed: 12/28/2022]
Abstract
The Brevinin peptides are antimicrobial agents obtained from frog skin secretions. Brevinin-2R has attracted many attentions due to its very low hemolytic activity, cationic property, and high affinity to cancer cells. Moreover, it has shown little toxicity against normal mammalian cells, while having killed several tumor cell lines by activation of lysosome-mitochondrial death pathway. In this review, we introduced the Brevinin superfamily with a focus on its therapeutic applications. Next, some unique properties of Brevinins were briefly discussed, including their ability to stimulate insulin secretion, dendritic cell maturation, and wound healing. In this context, we also provide information about the decoration of nanoparticles, such as cerium nano-oxide, by Brevinins. Finally, we addressed their potential for anti-tumor and drug design applications.
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Affiliation(s)
- Fatemeh Zohrab
- 1Department of Medical Biotechnology, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Saeedeh Askarian
- Torbat Heydariyeh University of Medical Sciences, Torbat Heydariyeh, Iran
| | - Amin Jalili
- 1Department of Medical Biotechnology, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Reza Kazemi Oskuee
- 3Neurogenic Inflammation Research Center, Mashhad University of Medical Sciences, Mashhad, Iran
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14
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Sang M, Wu Q, Xi X, Ma C, Wang L, Zhou M, Burrows JF, Chen T. Identification and target-modifications of temporin-PE: A novel antimicrobial peptide in the defensive skin secretions of the edible frog, Pelophylax kl. esculentus. Biochem Biophys Res Commun 2017; 495:2539-2546. [PMID: 29191658 DOI: 10.1016/j.bbrc.2017.11.173] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2017] [Accepted: 11/27/2017] [Indexed: 12/13/2022]
Abstract
A potent natural antimicrobial peptide named temporin-PE was identified and encoded from the skin secretions of Pelophylax kl. esculentus via "shotgun" cloning and LC-MS/MS fragmentation analysis. Target-modifications were carried out to further enhance the antimicrobial and anti-proliferative bioactivities, whilst decreasing the hemolytic effect. A range of bioassays demonstrated that replacing a proline with a tyrosine residue resulted in a loss of the bioactivity against Gram-negative bacteria, but dramatically improved the hemolytic and anti-proliferative activity, indicating the FLP- motif influences the hemolytic activity of temporins. Moreover, the coupling of TAT to the peptide dramatically improved its antimicrobial activity, indicating coupling TAT to these peptides could be considered as a potential tool to improve their antimicrobial activity. Overall, we have shown that targeted modifications of this natural antimicrobial peptide can adjust its bioactivities to help its development as an antibiotic or anti-proliferative agent.
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Affiliation(s)
- Mengru Sang
- School of Pharmacy, Nanjing University of Chinese Medicine, Nanjing, Jiangsu, 210023, China; School of Pharmacy, Queen's University, Belfast BT9 7BL, Northern Ireland, UK
| | - Qinan Wu
- School of Pharmacy, Nanjing University of Chinese Medicine, Nanjing, Jiangsu, 210023, China; Collaborative Innovation Centre of Chinese Medicinal Resources Industrialization, Nanjing, Jiangsu, 210023, China; National and Local Collaborative Engineering, Centre of Chinese Medicinal Resources Industrialization and Formulae Innovative Medicine, Nanjing, Jiangsu, 210023, China.
| | - Xinping Xi
- School of Pharmacy, Queen's University, Belfast BT9 7BL, Northern Ireland, UK.
| | - Chengbang Ma
- School of Pharmacy, Queen's University, Belfast BT9 7BL, Northern Ireland, UK
| | - Lei Wang
- School of Pharmacy, Queen's University, Belfast BT9 7BL, Northern Ireland, UK
| | - Mei Zhou
- School of Pharmacy, Queen's University, Belfast BT9 7BL, Northern Ireland, UK
| | - James F Burrows
- School of Pharmacy, Queen's University, Belfast BT9 7BL, Northern Ireland, UK
| | - Tianbao Chen
- School of Pharmacy, Queen's University, Belfast BT9 7BL, Northern Ireland, UK
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15
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Knudsen R, Henriksen EH, Gjelland KØ, Hansen H, Hendrichsen DK, Kristoffersen R, Olstad K. Are hybrids between Atlantic salmon and brown trout suitable long-term hosts of Gyrodactylus salaris during winter? JOURNAL OF FISH DISEASES 2017; 40:1299-1307. [PMID: 28105680 DOI: 10.1111/jfd.12602] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/14/2016] [Revised: 11/22/2016] [Accepted: 11/23/2016] [Indexed: 06/06/2023]
Abstract
The monogenean parasite Gyrodactylus salaris poses serious threats to many Atlantic salmon populations and presents many conservation and management questions/foci and challenges. It is therefore critical to identify potential vectors for infection. To test whether hybrids of native Atlantic salmon (Salmo salar) × brown trout (Salmo trutta) are suitable as reservoir hosts for G. salaris during winter, infected hybrid parr were released into a natural subarctic brook in the autumn. Six months later, 23.9% of the pit-tagged fish were recaptured. During the experimental period, the hybrids had a sixfold increase in mean intensity of G. salaris, while the prevalence decreased from 81% to 35%. There was high interindividual hybrid variability in susceptibility to infections. The maximum infrapopulation growth rate (0.018 day-1 ) of G. salaris throughout the winter was comparable to earlier laboratory experiments at similar temperatures. The results confirm that infrapopulations of G. salaris may reproduce on a hybrid population for several generations at low water temperatures (~1 °C). Wild salmon-trout hybrids are undoubtedly susceptible to G. salaris and represent an important reservoir host for the parasite independent of other co-occurring susceptible hosts. Consequently, these hybrids may pose a serious risk for G. salaris transmission to nearby, uninfected rivers by migratory individuals.
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Affiliation(s)
- R Knudsen
- Department of Arctic and Marine Biology, UiT The Arctic University of Norway, Tromsø, Norway
| | - E H Henriksen
- Department of Arctic and Marine Biology, UiT The Arctic University of Norway, Tromsø, Norway
| | - K Ø Gjelland
- Fram Centre, Norwegian Institute for Nature Research, Tromsø, Norway
| | - H Hansen
- Norwegian Veterinary Institute, Oslo, Norway
| | | | - R Kristoffersen
- Department of Arctic and Marine Biology, UiT The Arctic University of Norway, Tromsø, Norway
| | - K Olstad
- Norwegian Institute for Nature Research, Lillehammer, Norway
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16
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Jiang Y, Fan W, Xu J. De novo transcriptome analysis and antimicrobial peptides screening in skin of Paa boulengeri. Genes Genomics 2017. [DOI: 10.1007/s13258-017-0532-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
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17
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Davis LR, Klonoski K, Rutschow HL, Van Wijk KJ, Sun Q, Haribal MM, Saporito RA, Vega A, Rosenblum EB, Zamudio KR, Robertson JM. Host Defense Skin Peptides Vary with Color Pattern in the Highly Polymorphic Red-Eyed Treefrog. Front Ecol Evol 2016. [DOI: 10.3389/fevo.2016.00097] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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18
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Rebollar EA, Antwis RE, Becker MH, Belden LK, Bletz MC, Brucker RM, Harrison XA, Hughey MC, Kueneman JG, Loudon AH, McKenzie V, Medina D, Minbiole KPC, Rollins-Smith LA, Walke JB, Weiss S, Woodhams DC, Harris RN. Using "Omics" and Integrated Multi-Omics Approaches to Guide Probiotic Selection to Mitigate Chytridiomycosis and Other Emerging Infectious Diseases. Front Microbiol 2016; 7:68. [PMID: 26870025 PMCID: PMC4735675 DOI: 10.3389/fmicb.2016.00068] [Citation(s) in RCA: 81] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2015] [Accepted: 01/14/2016] [Indexed: 12/20/2022] Open
Abstract
Emerging infectious diseases in wildlife are responsible for massive population declines. In amphibians, chytridiomycosis caused by Batrachochytrium dendrobatidis, Bd, has severely affected many amphibian populations and species around the world. One promising management strategy is probiotic bioaugmentation of antifungal bacteria on amphibian skin. In vivo experimental trials using bioaugmentation strategies have had mixed results, and therefore a more informed strategy is needed to select successful probiotic candidates. Metagenomic, transcriptomic, and metabolomic methods, colloquially called "omics," are approaches that can better inform probiotic selection and optimize selection protocols. The integration of multiple omic data using bioinformatic and statistical tools and in silico models that link bacterial community structure with bacterial defensive function can allow the identification of species involved in pathogen inhibition. We recommend using 16S rRNA gene amplicon sequencing and methods such as indicator species analysis, the Kolmogorov-Smirnov Measure, and co-occurrence networks to identify bacteria that are associated with pathogen resistance in field surveys and experimental trials. In addition to 16S amplicon sequencing, we recommend approaches that give insight into symbiont function such as shotgun metagenomics, metatranscriptomics, or metabolomics to maximize the probability of finding effective probiotic candidates, which can then be isolated in culture and tested in persistence and clinical trials. An effective mitigation strategy to ameliorate chytridiomycosis and other emerging infectious diseases is necessary; the advancement of omic methods and the integration of multiple omic data provide a promising avenue toward conservation of imperiled species.
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Affiliation(s)
- Eria A. Rebollar
- Department of Biology, James Madison UniversityHarrisonburg, VA, USA
| | - Rachael E. Antwis
- Unit for Environmental Sciences and Management, North-West UniversityPotchefstroom, South Africa
- Institute of Zoology, Zoological Society of LondonLondon, UK
- School of Environment and Life Sciences, University of SalfordSalford, UK
| | - Matthew H. Becker
- Center for Conservation and Evolutionary Genetics, Smithsonian Conservation Biology Institute, National Zoological ParkWashington, DC, USA
| | - Lisa K. Belden
- Department of Biological Sciences, Virginia TechBlacksburg, VA, USA
| | - Molly C. Bletz
- Zoological Institute, Technische Universität BraunschweigBraunschweig, Germany
| | | | | | - Myra C. Hughey
- Department of Biological Sciences, Virginia TechBlacksburg, VA, USA
| | - Jordan G. Kueneman
- Department of Ecology and Evolutionary Biology, University of ColoradoBoulder, CO, USA
| | - Andrew H. Loudon
- Department of Zoology, Biodiversity Research Centre, University of British ColumbiaVancouver, BC, Canada
| | - Valerie McKenzie
- Department of Ecology and Evolutionary Biology, University of ColoradoBoulder, CO, USA
| | - Daniel Medina
- Department of Biological Sciences, Virginia TechBlacksburg, VA, USA
| | | | - Louise A. Rollins-Smith
- Department of Pathology, Microbiology and Immunology and Department of Pediatrics, Vanderbilt University School of Medicine, Department of Biological Sciences, Vanderbilt UniversityNashville, TN, USA
| | - Jenifer B. Walke
- Department of Biological Sciences, Virginia TechBlacksburg, VA, USA
| | - Sophie Weiss
- Department of Chemical and Biological Engineering, University of Colorado at BoulderBoulder, CO, USA
| | | | - Reid N. Harris
- Department of Biology, James Madison UniversityHarrisonburg, VA, USA
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19
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Van Rooij P, Martel A, Haesebrouck F, Pasmans F. Amphibian chytridiomycosis: a review with focus on fungus-host interactions. Vet Res 2015; 46:137. [PMID: 26607488 PMCID: PMC4660679 DOI: 10.1186/s13567-015-0266-0] [Citation(s) in RCA: 114] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2015] [Accepted: 10/05/2015] [Indexed: 01/30/2023] Open
Abstract
Amphibian declines and extinctions are emblematic for the current sixth mass extinction event. Infectious drivers of these declines include the recently emerged fungal pathogens Batrachochytrium dendrobatidis and Batrachochytrium salamandrivorans (Chytridiomycota). The skin disease caused by these fungi is named chytridiomycosis and affects the vital function of amphibian skin. Not all amphibians respond equally to infection and host responses might range from resistant, over tolerant to susceptible. The clinical outcome of infection is highly dependent on the amphibian host, the fungal virulence and environmental determinants. B. dendrobatidis infects the skin of a large range of anurans, urodeles and caecilians, whereas to date the host range of B. salamandrivorans seems limited to urodeles. So far, the epidemic of B. dendrobatidis is mainly limited to Australian, neotropical, South European and West American amphibians, while for B. salamandrivorans it is limited to European salamanders. Other striking differences between both fungi include gross pathology and thermal preferences. With this review we aim to provide the reader with a state-of-the art of host-pathogen interactions for both fungi, in which new data pertaining to the interaction of B. dendrobatidis and B. salamandrivorans with the host’s skin are integrated. Furthermore, we pinpoint areas in which more detailed studies are necessary or which have not received the attention they merit.
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Affiliation(s)
- Pascale Van Rooij
- Laboratory of Veterinary Bacteriology and Mycology, Department of Pathology, Bacteriology and Avian Diseases, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium.
| | - An Martel
- Laboratory of Veterinary Bacteriology and Mycology, Department of Pathology, Bacteriology and Avian Diseases, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium.
| | - Freddy Haesebrouck
- Laboratory of Veterinary Bacteriology and Mycology, Department of Pathology, Bacteriology and Avian Diseases, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium.
| | - Frank Pasmans
- Laboratory of Veterinary Bacteriology and Mycology, Department of Pathology, Bacteriology and Avian Diseases, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium.
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20
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Fasola E, Ribeiro R, Lopes I. Microevolution due to pollution in amphibians: A review on the genetic erosion hypothesis. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2015; 204:181-190. [PMID: 25969378 DOI: 10.1016/j.envpol.2015.04.027] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/08/2014] [Revised: 04/18/2015] [Accepted: 04/27/2015] [Indexed: 06/04/2023]
Abstract
The loss of genetic diversity, due to exposure to chemical contamination (genetic erosion), is a major threat to population viability. Genetic erosion is the loss of genetic variation: the loss of alleles determining the value of a specific trait or set of traits. Almost a third of the known amphibian species is considered to be endangered and a decrease of genetic variability can push them to the verge of extinction. This review indicates that loss of genetic variation due to chemical contamination has effects on: 1) fitness, 2) environmental plasticity, 3) co-tolerance mechanisms, 4) trade-off mechanisms, and 5) tolerance to pathogens in amphibian populations.
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Affiliation(s)
- E Fasola
- Department of Biology & CESAM (Centro de Estudos do Ambiente e do Mar), University of Aveiro, Campus de Santiago, 3810-193 Aveiro, Portugal.
| | - R Ribeiro
- CFE - Centre for Functional Ecology, Department of Life Sciences, University of Coimbra, Calçada Martim de Freitas, 3000-456 Coimbra, Portugal
| | - I Lopes
- Department of Biology & CESAM (Centro de Estudos do Ambiente e do Mar), University of Aveiro, Campus de Santiago, 3810-193 Aveiro, Portugal
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21
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Czirják GÁ, Köbölkuti LB, Tenk M, Szakács A, Kelemen A, Spînu M. Hemorrhagic stomatitis in a natural hybrid of Vipera ammodytes × Vipera berus due to inappropriate substrate in terrarium. J Vet Med Sci 2015; 77:701-3. [PMID: 25715871 PMCID: PMC4488407 DOI: 10.1292/jvms.14-0305] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
A natural hybrid of Vipera ammodytes × Vipera berus was
presented having low body weight, seizures and generalized swelling of the cephalic
region. Based on the history of the case and clinical examination, hemorrhagic stomatitis
of traumatic origin was diagnosed. The snake was kept in a terrarium with wood chips as a
substrate, and the material had induced trauma in the oral mucosa which was further
complicated with Salmonella Arizonae and Morganella
morganii co-infection, abscessation and osteomyelitis. To the best of the
authors’ knowledge, this is the first reported case of bacterial infection in European
snake hybrids and one of a few case reports in European snakes. Although wood chips are an
inexpensive substrate, based on our findings, they should be avoided when keeping and
breeding European vipers.
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Affiliation(s)
- Gábor Árpád Czirják
- Department of Infectious Diseases, Faculty of Veterinary Medicine, University of Agricultural Sciences and Veterinary Medicine, Mănăștur str. 3-5, 400372 Cluj-Napoca, Romania
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Longo AV, Burrowes PA, Zamudio KR. Genomic Studies of Disease-Outcome in Host-Pathogen Dynamics. Integr Comp Biol 2014; 54:427-38. [DOI: 10.1093/icb/icu073] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
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Walke JB, Becker MH, Loftus SC, House LL, Cormier G, Jensen RV, Belden LK. Amphibian skin may select for rare environmental microbes. ISME JOURNAL 2014; 8:2207-17. [PMID: 24858782 DOI: 10.1038/ismej.2014.77] [Citation(s) in RCA: 169] [Impact Index Per Article: 16.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/26/2013] [Revised: 02/26/2014] [Accepted: 04/08/2014] [Indexed: 12/12/2022]
Abstract
Host-microbe symbioses rely on the successful transmission or acquisition of symbionts in each new generation. Amphibians host a diverse cutaneous microbiota, and many of these symbionts appear to be mutualistic and may limit infection by the chytrid fungus, Batrachochytrium dendrobatidis, which has caused global amphibian population declines and extinctions in recent decades. Using bar-coded 454 pyrosequencing of the 16S rRNA gene, we addressed the question of symbiont transmission by examining variation in amphibian skin microbiota across species and sites and in direct relation to environmental microbes. Although acquisition of environmental microbes occurs in some host-symbiont systems, this has not been extensively examined in free-living vertebrate-microbe symbioses. Juvenile bullfrogs (Rana catesbeiana), adult red-spotted newts (Notophthalmus viridescens), pond water and pond substrate were sampled at a single pond to examine host-specificity and potential environmental transmission of microbiota. To assess population level variation in skin microbiota, adult newts from two additional sites were also sampled. Cohabiting bullfrogs and newts had distinct microbial communities, as did newts across the three sites. The microbial communities of amphibians and the environment were distinct; there was very little overlap in the amphibians' core microbes and the most abundant environmental microbes, and the relative abundances of OTUs that were shared by amphibians and the environment were inversely related. These results suggest that, in a host species-specific manner, amphibian skin may select for microbes that are generally in low abundance in the environment.
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Affiliation(s)
- Jenifer B Walke
- Department of Biological Sciences, Virginia Tech, Blacksburg, Virginia, USA
| | - Matthew H Becker
- Department of Biological Sciences, Virginia Tech, Blacksburg, Virginia, USA
| | - Stephen C Loftus
- Department of Statistics, Virginia Tech, Blacksburg, Virginia, USA
| | - Leanna L House
- Department of Statistics, Virginia Tech, Blacksburg, Virginia, USA
| | - Guy Cormier
- Department of Biological Sciences, Virginia Tech, Blacksburg, Virginia, USA
| | - Roderick V Jensen
- Department of Biological Sciences, Virginia Tech, Blacksburg, Virginia, USA
| | - Lisa K Belden
- Department of Biological Sciences, Virginia Tech, Blacksburg, Virginia, USA
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Woodhams DC, Brandt H, Baumgartner S, Kielgast J, Küpfer E, Tobler U, Davis LR, Schmidt BR, Bel C, Hodel S, Knight R, McKenzie V. Interacting symbionts and immunity in the amphibian skin mucosome predict disease risk and probiotic effectiveness. PLoS One 2014; 9:e96375. [PMID: 24789229 PMCID: PMC4005770 DOI: 10.1371/journal.pone.0096375] [Citation(s) in RCA: 138] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2014] [Accepted: 04/04/2014] [Indexed: 01/21/2023] Open
Abstract
Pathogenesis is strongly dependent on microbial context, but development of probiotic therapies has neglected the impact of ecological interactions. Dynamics among microbial communities, host immune responses, and environmental conditions may alter the effect of probiotics in human and veterinary medicine, agriculture and aquaculture, and the proposed treatment of emerging wildlife and zoonotic diseases such as those occurring on amphibians or vectored by mosquitoes. Here we use a holistic measure of amphibian mucosal defenses to test the effects of probiotic treatments and to assess disease risk under different ecological contexts. We developed a non-invasive assay for antifungal function of the skin mucosal ecosystem (mucosome function) integrating host immune factors and the microbial community as an alternative to pathogen exposure experiments. From approximately 8500 amphibians sampled across Europe, we compared field infection prevalence with mucosome function against the emerging fungal pathogen Batrachochytrium dendrobatidis. Four species were tested with laboratory exposure experiments, and a highly susceptible species, Alytes obstetricans, was treated with a variety of temperature and microbial conditions to test the effects of probiotic therapies and environmental conditions on mucosome function. We found that antifungal function of the amphibian skin mucosome predicts the prevalence of infection with the fungal pathogen in natural populations, and is linked to survival in laboratory exposure experiments. When altered by probiotic therapy, the mucosome increased antifungal capacity, while previous exposure to the pathogen was suppressive. In culture, antifungal properties of probiotics depended strongly on immunological and environmental context including temperature, competition, and pathogen presence. Functional changes in microbiota with shifts in temperature provide an alternative mechanistic explanation for patterns of disease susceptibility related to climate beyond direct impact on host or pathogen. This nonlethal management tool can be used to optimize and quickly assess the relative benefits of probiotic therapies under different climatic, microbial, or host conditions.
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Affiliation(s)
- Douglas C. Woodhams
- Institute of Evolutionary Biology and Environmental Studies, University of Zurich, Zurich, Switzerland
- Department of Ecology and Evolutionary Biology, University of Colorado, Boulder, Colorado, United States of America
- * E-mail:
| | - Hannelore Brandt
- Institute of Evolutionary Biology and Environmental Studies, University of Zurich, Zurich, Switzerland
| | - Simone Baumgartner
- Institute of Evolutionary Biology and Environmental Studies, University of Zurich, Zurich, Switzerland
| | - Jos Kielgast
- Section for Freshwater Biology, Department of Biology, University of Copenhagen, Copenhagen, Denmark
| | - Eliane Küpfer
- Institute of Evolutionary Biology and Environmental Studies, University of Zurich, Zurich, Switzerland
- Department of Evolutionary Biology, Technical University of Braunschweig, Braunschweig, Germany
| | - Ursina Tobler
- Institute of Evolutionary Biology and Environmental Studies, University of Zurich, Zurich, Switzerland
- KARCH, Neuchâtel, Switzerland
| | - Leyla R. Davis
- Institute of Evolutionary Biology and Environmental Studies, University of Zurich, Zurich, Switzerland
| | - Benedikt R. Schmidt
- Institute of Evolutionary Biology and Environmental Studies, University of Zurich, Zurich, Switzerland
- KARCH, Neuchâtel, Switzerland
| | - Christian Bel
- Institute of Evolutionary Biology and Environmental Studies, University of Zurich, Zurich, Switzerland
| | - Sandro Hodel
- Institute of Evolutionary Biology and Environmental Studies, University of Zurich, Zurich, Switzerland
| | - Rob Knight
- Howard Hughes Medical Institute and Department of Chemistry and Biochemistry, BioFrontiers Institute, University of Colorado, Boulder, Colorado, United States of America
| | - Valerie McKenzie
- Department of Ecology and Evolutionary Biology, University of Colorado, Boulder, Colorado, United States of America
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Holden WM, Fites JS, Reinert LK, Rollins-Smith LA. Nikkomycin Z is an effective inhibitor of the chytrid fungus linked to global amphibian declines. Fungal Biol 2013; 118:48-60. [PMID: 24433676 DOI: 10.1016/j.funbio.2013.11.001] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2013] [Revised: 10/31/2013] [Accepted: 11/05/2013] [Indexed: 11/16/2022]
Abstract
Fungal infections in humans, wildlife, and plants are a growing concern because of their devastating effects on human and ecosystem health. In recent years, populations of many amphibian species have declined, and some have become extinct due to chytridiomycosis caused by the fungal pathogen Batrachochytrium dendrobatidis. For some endangered amphibian species, captive colonies are the best intermediate solution towards eventual reintroduction, and effective antifungal treatments are needed to cure chytridiomycosis and limit the spread of this pathogen in such survival assurance colonies. Currently, the best accepted treatment for infected amphibians is itraconazole, but its toxic side effects reduce its usefulness for many species. Safer antifungal treatments are needed for disease control. Here, we show that nikkomycin Z, a chitin synthase inhibitor, dramatically alters the cell wall stability of B. dendrobatidis cells and completely inhibits growth of B. dendrobatidis at 250 μM. Low doses of nikkomycin Z enhanced the effectiveness of natural antimicrobial skin peptide mixtures tested in vitro. These studies suggest that nikkomycin Z would be an effective treatment to significantly reduce the fungal burden in frogs infected by B. dendrobatidis.
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Affiliation(s)
- Whitney M Holden
- Department of Pathology, Microbiology and Immunology, Vanderbilt University School of Medicine, Nashville, TN 37232, USA.
| | - J Scott Fites
- Department of Biological Sciences, Vanderbilt University, Nashville, TN 37235, USA.
| | - Laura K Reinert
- Department of Pathology, Microbiology and Immunology, Vanderbilt University School of Medicine, Nashville, TN 37232, USA.
| | - Louise A Rollins-Smith
- Department of Pathology, Microbiology and Immunology, Vanderbilt University School of Medicine, Nashville, TN 37232, USA; Department of Biological Sciences, Vanderbilt University, Nashville, TN 37235, USA; Department of Pediatrics, Vanderbilt University School of Medicine, Nashville, TN 37232, USA.
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Chromosomal copy number variation, selection and uneven rates of recombination reveal cryptic genome diversity linked to pathogenicity. PLoS Genet 2013; 9:e1003703. [PMID: 23966879 PMCID: PMC3744429 DOI: 10.1371/journal.pgen.1003703] [Citation(s) in RCA: 97] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2012] [Accepted: 06/21/2013] [Indexed: 11/19/2022] Open
Abstract
Pathogenic fungi constitute a growing threat to both plant and animal species on a global scale. Despite a clonal mode of reproduction dominating the population genetic structure of many fungi, putatively asexual species are known to adapt rapidly when confronted by efforts to control their growth and transmission. However, the mechanisms by which adaptive diversity is generated across a clonal background are often poorly understood. We sequenced a global panel of the emergent amphibian pathogen, Batrachochytrium dendrobatidis (Bd), to high depth and characterized rapidly changing features of its genome that we believe hold the key to the worldwide success of this organism. Our analyses show three processes that contribute to the generation of de novo diversity. Firstly, we show that the majority of wild isolates manifest chromosomal copy number variation that changes over short timescales. Secondly, we show that cryptic recombination occurs within all lineages of Bd, leading to large regions of the genome being in linkage equilibrium, and is preferentially associated with classes of genes of known importance for virulence in other pathosystems. Finally, we show that these classes of genes are under directional selection, and that this has predominantly targeted the Global Panzootic Lineage (BdGPL). Our analyses show that Bd manifests an unusually dynamic genome that may have been shaped by its association with the amphibian host. The rates of variation that we document likely explain the high levels of phenotypic variability that have been reported for Bd, and suggests that the dynamic genome of this pathogen has contributed to its success across multiple biomes and host-species. Pathogenic fungi constitute a growing threat to both plant and animal species on a global scale. However, many features of the fungal genome that enable them to successfully adapt to infect diverse hosts and ecological niches remain cryptic, especially for newly evolved emerging lineages. In this paper, we report three novel features of genome diversity linked to pathogenicity in the emerging amphibian pathogen, Batrachochytrium dendrobatidis (Bd). Firstly, we identified widespread chromosome copy number variation (CCNV) across our lineages, with individual isolates harboring between 2 to 5 copies of each chromosome and rapid rates of CCNV occurring in culture. In addition, by using in vitro divergence of replicate lines of Bd, we showed that changes in ploidy can occur within as few as 40 generations. Secondly, we identified uneven rates of recombination across the genomes and lineages, revealing hot spots in known classes of virulence factors. Finally we identified significant evidence of diversifying selection across the secretome of Bd, and showed that selection also targets putative virulence factors. These findings add to our knowledge of genome-dynamicity and modes of evolution manifested by eukaryote microbial pathogens, and may explain the varied phenotypic responses observed in Bd.
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Mechkarska M, Prajeep M, Leprince J, Vaudry H, Meetani MA, Evans BJ, Conlon JM. A comparison of host-defense peptides in skin secretions of female Xenopus laevis × Xenopus borealis and X. borealis × X. laevis F1 hybrids. Peptides 2013; 45:1-8. [PMID: 23624316 DOI: 10.1016/j.peptides.2013.04.008] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/07/2013] [Revised: 04/15/2013] [Accepted: 04/17/2013] [Indexed: 12/30/2022]
Abstract
Peptidomic analysis was used to compare the diversity of host-defense peptides in norepinephrine-stimulated skin secretions from laboratory-generated female F1 hybrids of Xenopus laevis and Xenopus borealis (Pipidae). Skin secretions of hybrids with maternal X. laevis (XLB) contained 12 antimicrobial peptides (AMPs), comprising 8 from X. laevis and 4 from X. borealis. Magainin-B1, XPF-B1, PGLa-B1 CPF-B2, CPF-B3 and CPF-B4 from X. borealis and XPF-1, XPF-2, and CPF-6 from X. laevis were not detected and CPF-1 and CPF-7 were present in low concentration. The secretions contained caerulein and caerulein-B1 derived from both parents but lacked X. laevis xenopsin and X. borealis caerulein-B2. Skin secretions of hybrids with maternal X. borealis (XBL) contained 14 AMPs comprising 6 from X. borealis and 8 from X. laevis. Magainin-B1, XPF-B1, PGLa-B1, CPF-B2, XPF-1, CPF-5, and CPF-7 were absent and CPF-B3, CPF-B4, CPF-1 and CPF-6 were present only in low concentration. Xenopsin and caerulein were identified in the secretions but caerulein-B2 was absent and caerulein-B1 was present in low concentration. No peptides were identified in secretions of either XLB or XBL hybrids that were not present in the parental species. The data indicate that hybridization between X. laevis and X. borealis results in increased diversity of host-defense peptides in skin secretions but point to extensive AMP gene silencing compared with previously studied female X. laevis×X. muelleri F1 hybrids and no novel peptide expression.
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Affiliation(s)
- Milena Mechkarska
- Department of Biochemistry, College of Medicine and Health Sciences, United Arab Emirates University, Al Ain, United Arab Emirates
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