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Kharel A, Rookes J, Ziemann M, Cahill D. Viable protoplast isolation, organelle visualization and transformation of the globally distributed plant pathogen Phytophthora cinnamomi. PROTOPLASMA 2024; 261:1073-1092. [PMID: 38702562 PMCID: PMC11358197 DOI: 10.1007/s00709-024-01953-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/02/2023] [Accepted: 04/11/2024] [Indexed: 05/06/2024]
Abstract
Phytophthora cinnamomi is an oomycete plant pathogen with a host range of almost 5000 plant species worldwide and therefore poses a serious threat to biodiversity. Omics technology has provided significant progress in our understanding of oomycete biology, however, transformation studies of Phytophthora for gene functionalisation are still in their infancy. Only a limited number of Phytophthora species have been successfully transformed and gene edited to elucidate the role of particular genes. There is a need to escalate our efforts to understand molecular processes, gene regulation and infection mechanisms of the pathogen to enable us to develop new disease management strategies. The primary obstacle hindering the advancement of transformation studies in Phytophthora is their challenging and unique nature, coupled with our limited comprehension of why they remain such an intractable system to work with. In this study, we have identified some of the key factors associated with the recalcitrant nature of P. cinnamomi. We have incorporated fluorescence microscopy and flow cytometry along with the organelle-specific dyes, fluorescein diacetate, Hoechst 33342 and MitoTracker™ Red CMXRos, to assess P. cinnamomi-derived protoplast populations. This approach has also provided valuable insights into the broader cell biology of Phytophthora. Furthermore, we have optimized the crucial steps that allow transformation of P. cinnamomi and have generated transformed isolates that express a cyan fluorescent protein, with a transformation efficiency of 19.5%. We therefore provide a platform for these methodologies to be applied for the transformation of other Phytophthora species and pave the way for future gene functionalisation studies.
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Affiliation(s)
- Aayushree Kharel
- School of Life and Environmental Sciences, Deakin University, Geelong Waurn Ponds Campus, Waurn Ponds, VIC, 3216, Australia
| | - James Rookes
- School of Life and Environmental Sciences, Deakin University, Geelong Waurn Ponds Campus, Waurn Ponds, VIC, 3216, Australia
| | - Mark Ziemann
- School of Life and Environmental Sciences, Deakin University, Geelong Waurn Ponds Campus, Waurn Ponds, VIC, 3216, Australia
- Burnet Institute, Melbourne, Australia
| | - David Cahill
- School of Life and Environmental Sciences, Deakin University, Geelong Waurn Ponds Campus, Waurn Ponds, VIC, 3216, Australia.
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2
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Timanikova N, Fletcher K, Han JW, van West P, Woodward S, Kim GH, Küpper FC, Wenzel M. Macroalgal eukaryotic microbiome composition indicates novel phylogenetic diversity and broad host spectrum of oomycete pathogens. Environ Microbiol 2024; 26:e16656. [PMID: 38818657 DOI: 10.1111/1462-2920.16656] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2023] [Accepted: 05/07/2024] [Indexed: 06/01/2024]
Abstract
Seaweeds are important components of marine ecosystems with emerging potential in aquaculture and as sources of biofuel, food products and pharmacological compounds. However, an increasingly recognised threat to natural and industrial seaweed populations is infection with parasitic single-celled eukaryotes from the relatively understudied oomycete lineage. Here we examine the eukaryomes of diverse brown, red and green marine macroalgae collected from polar (Baffin Island), cold-temperate (Falkland Islands) and tropical (Ascension Island) locations, with a focus on oomycete and closely related diatom taxa. Using 18S rRNA gene amplicon sequencing, we show unexpected genetic and taxonomic diversity of the eukaryomes, a strong broad-brush association between eukaryome composition and geographic location, and some evidence of association between eukaryome structure and macroalgal phylogenetic relationships (phylosymbiosis). However, the oomycete fraction of the eukaryome showed disparate patterns of diversity and structure, highlighting much weaker association with geography and no evidence of phylosymbiosis. We present several novel haplotypes of the most common oomycete Eurychasma dicksonii and report for the first time a cosmopolitan distribution and absence of host specificity of this important pathogen. This indicates rich diversity in macroalgal oomycete pathogens and highlights that these pathogens may be generalist and highly adaptable to diverse environmental conditions.
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Affiliation(s)
| | - Kyle Fletcher
- School of Biological Sciences, University of Aberdeen, Aberdeen, UK
- Oceanlab, University of Aberdeen, Newburgh, UK
- Aberdeen Oomycete Laboratory, International Centre for Aquaculture Research and Development, Institute of Medical Sciences, University of Aberdeen, Aberdeen, UK
| | - Jon-Wong Han
- Kongju National University, Gongju, South Chungcheong Province, South Korea
| | - Pieter van West
- Aberdeen Oomycete Laboratory, International Centre for Aquaculture Research and Development, Institute of Medical Sciences, University of Aberdeen, Aberdeen, UK
| | - Steve Woodward
- School of Biological Sciences, University of Aberdeen, Aberdeen, UK
| | - Gwang-Hoon Kim
- Kongju National University, Gongju, South Chungcheong Province, South Korea
| | - Frithjof C Küpper
- School of Biological Sciences, University of Aberdeen, Aberdeen, UK
- Kongju National University, Gongju, South Chungcheong Province, South Korea
- Marine Biodiscovery Centre, Department of Chemistry, University of Aberdeen, Aberdeen, UK
- Department of Chemistry and Biochemistry, San Diego State University, California, San Diego, California, USA
| | - Marius Wenzel
- School of Biological Sciences, University of Aberdeen, Aberdeen, UK
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Botkin J, Chanda AK, Martin FN, Hirsch CD. A Reference Genome Sequence Resource for the Sugar Beet Root Rot Pathogen Aphanomyces cochlioides. MOLECULAR PLANT-MICROBE INTERACTIONS : MPMI 2022; 35:706-710. [PMID: 35834412 DOI: 10.1094/mpmi-11-21-0277-a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Affiliation(s)
- Jacob Botkin
- Department of Plant Pathology, University of Minnesota, St. Paul, MN 55108, U.S.A
| | - Ashok K Chanda
- Department of Plant Pathology, University of Minnesota, St. Paul, MN 55108, U.S.A
- University of Minnesota, Northwest Research and Outreach Center, Crookston, MN 56716, U.S.A
| | - Frank N Martin
- USDA, Agricultural Research Service, Salinas, CA 93905, U.S.A
| | - Cory D Hirsch
- Department of Plant Pathology, University of Minnesota, St. Paul, MN 55108, U.S.A
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Kiselev A, San Clemente H, Camborde L, Dumas B, Gaulin E. A Comprehensive Assessment of the Secretome Responsible for Host Adaptation of the Legume Root Pathogen Aphanomyces euteiches. J Fungi (Basel) 2022; 8:88. [PMID: 35050028 PMCID: PMC8780586 DOI: 10.3390/jof8010088] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2021] [Revised: 01/09/2022] [Accepted: 01/14/2022] [Indexed: 01/27/2023] Open
Abstract
The soil-borne oomycete pathogen Aphanomyces euteiches causes devastating root rot diseases in legumes such as pea and alfalfa. The different pathotypes of A. euteiches have been shown to exhibit differential quantitative virulence, but the molecular basis of host adaptation has not yet been clarified. Here, we re-sequenced a pea field reference strain of A. euteiches ATCC201684 with PacBio long-reads and took advantage of the technology to generate the mitochondrial genome. We identified that the secretome of A. euteiches is characterized by a large portfolio of secreted proteases and carbohydrate-active enzymes (CAZymes). We performed Illumina sequencing of four strains of A. euteiches with contrasted specificity to pea or alfalfa and found in different geographical areas. Comparative analysis showed that the core secretome is largely represented by CAZymes and proteases. The specific secretome is mainly composed of a large set of small, secreted proteins (SSP) without any predicted functional domain, suggesting that the legume preference of the pathogen is probably associated with unknown functions. This study forms the basis for further investigations into the mechanisms of interaction of A. euteiches with legumes.
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Affiliation(s)
| | | | | | | | - Elodie Gaulin
- Laboratoire de Recherche en Sciences Végétales (LRSV), Université de Toulouse, CNRS, UPS, Toulouse INP, 31320 Toulouse, France; (A.K.); (H.S.C.); (L.C.); (B.D.)
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Xiao J, Liu J, Ma L, Hao X, Yu R, Yuan X. Mitogenomes of Nine Asian Skipper Genera and Their Phylogenetic Position (Lepidoptera: Hesperiidae: Pyrginae). INSECTS 2022; 13:68. [PMID: 35055910 PMCID: PMC8779469 DOI: 10.3390/insects13010068] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/15/2021] [Revised: 12/30/2021] [Accepted: 01/04/2022] [Indexed: 11/16/2022]
Abstract
In this study, complete mitochondrial genomes of nine species representing three tribes in the subfamily Pyrginae sensu lato were newly sequenced. The mitogenomes are closed double-stranded circular molecules, with the length ranging from 15,232 bp to 15,559 bp, which all encode 13 protein-coding genes (PCGs), two ribosomal RNA (rRNA) genes, 22 transfer RNA (tRNA) genes, and a control region. The orientation and gene order of these nine mitogenomes are identical to the inferred ancestral arrangement of insects. All PCGs exhibit the typical start codon ATN except for cox1 (using CGA) and cox2 (using TTG) in Mooreana trichoneura. Most of the PCGs terminate with a TAA stop codon, while cox1, cox2, nad4, and nad5 end with the incomplete codon single T. For the different datasets, we found that the one comprising all 37 genes of the mitogenome produced the highest nodal support, indicating that the inclusion of RNAs improves the phylogenetic signal. This study re-confirmed the status of Capila, Pseudocoladenia, and Sarangesa; namely, Capila belongs to the tribe Tagiadini, and Pseudocoladenia and Sarangesa to the tribe Celaenorrhini. Diagnostic characters distinguishing the two tribes, the length of the forewing cell and labial palpi, are no longer significant. Two populations of Pseudocoladenia dan fabia from China and Myanmar and P. dan dhyana from Thailand are confirmed as conspecific.
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Affiliation(s)
- Jintian Xiao
- Key Laboratory of Plant Protection Resources and Pest Management, Ministry of Education, Entomological Museum, College of Plant Protection, Northwest A&F University, Yangling, Xianyang 712100, China; (J.X.); (J.L.); (L.M.); (R.Y.)
| | - Jiaqi Liu
- Key Laboratory of Plant Protection Resources and Pest Management, Ministry of Education, Entomological Museum, College of Plant Protection, Northwest A&F University, Yangling, Xianyang 712100, China; (J.X.); (J.L.); (L.M.); (R.Y.)
| | - Luyao Ma
- Key Laboratory of Plant Protection Resources and Pest Management, Ministry of Education, Entomological Museum, College of Plant Protection, Northwest A&F University, Yangling, Xianyang 712100, China; (J.X.); (J.L.); (L.M.); (R.Y.)
| | - Xiangyu Hao
- College of Life Sciences, Northwest A&F University, Yangling, Xianyang 712100, China;
| | - Ruitao Yu
- Key Laboratory of Plant Protection Resources and Pest Management, Ministry of Education, Entomological Museum, College of Plant Protection, Northwest A&F University, Yangling, Xianyang 712100, China; (J.X.); (J.L.); (L.M.); (R.Y.)
| | - Xiangqun Yuan
- Key Laboratory of Plant Protection Resources and Pest Management, Ministry of Education, Entomological Museum, College of Plant Protection, Northwest A&F University, Yangling, Xianyang 712100, China; (J.X.); (J.L.); (L.M.); (R.Y.)
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Becking T, Kiselev A, Rossi V, Street-Jones D, Grandjean F, Gaulin E. Pathogenicity of animal and plant parasitic Aphanomyces spp and their economic impact on aquaculture and agriculture. FUNGAL BIOL REV 2021. [DOI: 10.1016/j.fbr.2021.08.001] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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Martín-Torrijos L, Martínez-Ríos M, Casabella-Herrero G, Adams SB, Jackson CR, Diéguez-Uribeondo J. Tracing the origin of the crayfish plague pathogen, Aphanomyces astaci, to the Southeastern United States. Sci Rep 2021; 11:9332. [PMID: 33927290 PMCID: PMC8085144 DOI: 10.1038/s41598-021-88704-8] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2020] [Accepted: 04/05/2021] [Indexed: 02/02/2023] Open
Abstract
The oomycete Aphanomyces astaci is an emerging infectious pathogen affecting freshwater crayfish worldwide and is responsible for one of the most severe wildlife pandemics ever reported. The pathogen has caused mass mortalities of freshwater crayfish species in Europe and Asia, and threatens other susceptible species in Madagascar, Oceania and South America. The pathogen naturally coexists with some North American crayfish species that are its chronic carriers. Presumptions that A. astaci originated in North America are based on disease outbreaks that followed translocations of North American crayfish and on the identification of the pathogen mainly in Europe. We studied A. astaci in the southeastern US, a center of freshwater crayfish diversity. In order to decipher the origin of the pathogen, we investigated (1) the distribution and haplotype diversity of A. astaci, and (2) whether there are crayfish species-specificities and/or geographical restrictions for A. astaci haplotypes. A total of 132 individuals, corresponding to 19 crayfish species and one shrimp species from 23 locations, tested positive for A. astaci. Mitochondrial rnnS and rnnL sequences indicated that A. astaci from the southeastern US exhibited the highest genetic diversity so far described for the pathogen (eight haplotypes, six of which we newly describe). Our findings that A. astaci is widely distributed and genetically diverse in the region supports the hypothesis that the pathogen originated in the southeastern US. In contrast to previous assumptions, however, the pathogen exhibited no clear species-specificity or geographical patterns.
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Affiliation(s)
- Laura Martín-Torrijos
- Department of Mycology, Real Jardín Botánico-CSIC, Plaza Murillo 2, 28014, Madrid, Spain.
| | - María Martínez-Ríos
- Department of Mycology, Real Jardín Botánico-CSIC, Plaza Murillo 2, 28014, Madrid, Spain
| | | | - Susan B Adams
- USDA Forest Service, Southern Research Station, Center for Bottomland Hardwoods Research, 1000 Front Street, Oxford, MS, 38655, USA
| | - Colin R Jackson
- Department of Biology, University of Mississippi, University, MS, 38677, USA
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Martín-Torrijos L, Correa-Villalona AJ, Pradillo A, Diéguez-Uribeondo J. Coexistence of Two Invasive Species, Procambarus clarkii and Aphanomyces astaci, in Brackish Waters of a Mediterranean Coastal Lagoon. Front Ecol Evol 2021. [DOI: 10.3389/fevo.2020.622434] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
Procambarus clarkii is a worldwide freshwater invasive crustacean from North America and was first introduced into Europe the 1970s. Along with P. clarkii, another invasive alien species was also spreading: Aphanomyces astaci. This pathogen is listed among the 100 World’s worst invasive species and involved in the European native crayfish decline. Although both species live in freshwater ecosystems, P. clarkii can withstand brackish waters and inhabit estuarine habitats. However, the presence of A. astaci associated to North American crayfishes has never been described in brackish waters. In this study, we have investigated the presence of A. astaci in a P. clarkii population of a Mediterranean coastal lagoon in the Albufera Natural Park, Valencia, Spain introduced in 1976. Our study confirmed the presence of this pathogen, and suggests that A. astaci has been spreading for more than four decades in the mentioned estuarine environment. Mitochondrial ribosomal rnnS and rnnL indicated that the isolated pathogen belongs to d1-haplotype (i.e., D-haplogroup) typically hosted by P. clarkii. The presence of this pathogen in a brackish environment may suggest a better adaptation than other A. astaci strains to adverse conditions, such as high salinity levels. This is a matter of concern for the conservation of European native freshwater crayfish and highlights once more the risk of introducing invasive alien crustaceans.
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10
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Mapping 15 years of crayfish plague in the Iberian Peninsula: The impact of two invasive species on the endangered native crayfish. PLoS One 2019; 14:e0219223. [PMID: 31393870 PMCID: PMC6687115 DOI: 10.1371/journal.pone.0219223] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2019] [Accepted: 06/19/2019] [Indexed: 12/04/2022] Open
Abstract
Crayfish plague, caused by the pathogen Aphanomyces astaci, is one of the main factors responsible for the decimation of the native European crayfish species Austropotamobius pallipes. In Spain, two North American freshwater crayfish species, Procambarus clarkii and Pacifastacus leniusculus, were intentionally introduced during the 1970s for aquaculture and fishery purposes. Since then, incidences of crayfish plague have been continually reported. In this work, we evaluated more than 50 diagnosed cases of crayfish plague that have occurred in the Iberian Peninsula since 2004 by performing a microscopic examination of infected specimens and by molecularly identifying and haplotyping the pathogen. Our results showed that (i) the pathogen A. astaci has been active 45 years since the first introductions of the invasive North American crayfish species in the Iberian Peninsula, and (ii) P. clarkii and P. leniusculus are chronic reservoirs of the crayfish plague pathogen. Moreover, our data confirmed a correspondence between pathogen origin and spread and the specific haplotypes carried by the North American invasive crayfish located in the vicinity of each outbreak. We generated a crayfish plague incidence map of the Iberian Peninsula that shows (i) a northern area, mainly inhabited by alien P. leniusculus, where crayfish plague cases are associated with the b-haplotype specific to P. leniusculus, and (ii) southern, central and eastern areas that are basically inhabited by alien P. clarkii, where crayfish plague cases are associated with the d1- and d2-haplotypes specific to P. clarkii. The results presented here are evidence of the long standing and negative impact of the two invasive crayfish species on the native species, indicating the need for more extensive control measures.
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11
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Molecular identification of oomycete species affecting aquaculture in Bangladesh. AQUACULTURE AND FISHERIES 2019. [DOI: 10.1016/j.aaf.2018.12.003] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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12
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McGowan J, Byrne KP, Fitzpatrick DA. Comparative Analysis of Oomycete Genome Evolution Using the Oomycete Gene Order Browser (OGOB). Genome Biol Evol 2019; 11:189-206. [PMID: 30535146 PMCID: PMC6330052 DOI: 10.1093/gbe/evy267] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/10/2018] [Indexed: 01/01/2023] Open
Abstract
The oomycetes are a class of microscopic, filamentous eukaryotes within the stramenopiles–alveolates–rhizaria eukaryotic supergroup. They include some of the most destructive pathogens of animals and plants, such as Phytophthora infestans, the causative agent of late potato blight. Despite the threat they pose to worldwide food security and natural ecosystems, there is a lack of tools and databases available to study oomycete genetics and evolution. To this end, we have developed the Oomycete Gene Order Browser (OGOB), a curated database that facilitates comparative genomic and syntenic analyses of oomycete species. OGOB incorporates genomic data for 20 oomycete species including functional annotations and a number of bioinformatics tools. OGOB hosts a robust set of orthologous oomycete genes for evolutionary analyses. Here, we present the structure and function of OGOB as well as a number of comparative genomic analyses we have performed to better understand oomycete genome evolution. We analyze the extent of oomycete gene duplication and identify tandem gene duplication as a driving force of the expansion of secreted oomycete genes. We identify core genes that are present and microsyntenically conserved (termed syntenologs) in oomycete lineages and identify the degree of microsynteny between each pair of the 20 species housed in OGOB. Consistent with previous comparative synteny analyses between a small number of oomycete species, our results reveal an extensive degree of microsyntenic conservation amongst genes with housekeeping functions within the oomycetes. OGOB is available at https://ogob.ie.
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Affiliation(s)
- Jamie McGowan
- Genome Evolution Laboratory, Department of Biology, Maynooth University, Co. Kildare, Ireland.,Human Health Research Institute, Maynooth University, Co. Kildare, Ireland
| | - Kevin P Byrne
- School of Medicine, UCD Conway Institute, University College Dublin, Ireland
| | - David A Fitzpatrick
- Genome Evolution Laboratory, Department of Biology, Maynooth University, Co. Kildare, Ireland.,Human Health Research Institute, Maynooth University, Co. Kildare, Ireland
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Fletcher K, Klosterman SJ, Derevnina L, Martin F, Bertier LD, Koike S, Reyes-Chin-Wo S, Mou B, Michelmore R. Comparative genomics of downy mildews reveals potential adaptations to biotrophy. BMC Genomics 2018; 19:851. [PMID: 30486780 PMCID: PMC6264045 DOI: 10.1186/s12864-018-5214-8] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2018] [Accepted: 10/31/2018] [Indexed: 12/05/2022] Open
Abstract
BACKGROUND Spinach downy mildew caused by the oomycete Peronospora effusa is a significant burden on the expanding spinach production industry, especially for organic farms where synthetic fungicides cannot be deployed to control the pathogen. P. effusa is highly variable and 15 new races have been recognized in the past 30 years. RESULTS We virulence phenotyped, sequenced, and assembled two isolates of P. effusa from the Salinas Valley, California, U.S.A. that were identified as race 13 and 14. These assemblies are high quality in comparison to assemblies of other downy mildews having low total scaffold count (784 & 880), high contig N50s (48 kb & 52 kb), high BUSCO completion and low BUSCO duplication scores and share many syntenic blocks with Phytophthora species. Comparative analysis of four downy mildew and three Phytophthora species revealed parallel absences of genes encoding conserved domains linked to transporters, pathogenesis, and carbohydrate activity in the biotrophic species. Downy mildews surveyed that have lost the ability to produce zoospores have a common loss of flagella/motor and calcium domain encoding genes. Our phylogenomic data support multiple origins of downy mildews from hemibiotrophic progenitors and suggest that common gene losses in these downy mildews may be of genes involved in the necrotrophic stages of Phytophthora spp. CONCLUSIONS We present a high-quality draft genome of Peronospora effusa that will serve as a reference for Peronospora spp. We identified several Pfam domains as under-represented in the downy mildews consistent with the loss of zoosporegenesis and necrotrophy. Phylogenomics provides further support for a polyphyletic origin of downy mildews.
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Affiliation(s)
- Kyle Fletcher
- The Genome Center, Genome and Biomedical Sciences Facility, University of California, 451 East Health Sciences Drive, Davis, CA 95616 USA
| | - Steven J. Klosterman
- United States Department of Agriculture, Agricultural Research Service, Salinas, CA 93905 USA
| | - Lida Derevnina
- The Genome Center, Genome and Biomedical Sciences Facility, University of California, 451 East Health Sciences Drive, Davis, CA 95616 USA
- Present Address: The Sainsbury Laboratory, Norwich Research Park, Norwich, NR4 7UH UK
| | - Frank Martin
- United States Department of Agriculture, Agricultural Research Service, Salinas, CA 93905 USA
| | - Lien D. Bertier
- The Genome Center, Genome and Biomedical Sciences Facility, University of California, 451 East Health Sciences Drive, Davis, CA 95616 USA
| | - Steven Koike
- UC Davis Cooperative Extension Monterey County, Salinas, CA 93901 USA
- Present Address: TriCal Diagnostics, Hollister, CA 95023 USA
| | - Sebastian Reyes-Chin-Wo
- The Genome Center, Genome and Biomedical Sciences Facility, University of California, 451 East Health Sciences Drive, Davis, CA 95616 USA
| | - Beiquan Mou
- United States Department of Agriculture, Agricultural Research Service, Salinas, CA 93905 USA
| | - Richard Michelmore
- The Genome Center, Genome and Biomedical Sciences Facility, University of California, 451 East Health Sciences Drive, Davis, CA 95616 USA
- Departments of Plant Sciences, Molecular & Cellular Biology, Medical Microbiology & Immunology, University of California, Davis, 95616 USA
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Aphanomyces invadans, the causal agent of Epizootic Ulcerative Syndrome, is a global threat to wild and farmed fish. FUNGAL BIOL REV 2018. [DOI: 10.1016/j.fbr.2018.05.002] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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15
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Martín-Torrijos L, Kawai T, Makkonen J, Jussila J, Kokko H, Diéguez-Uribeondo J. Crayfish plague in Japan: A real threat to the endemic Cambaroides japonicus. PLoS One 2018; 13:e0195353. [PMID: 29617418 PMCID: PMC5884544 DOI: 10.1371/journal.pone.0195353] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2018] [Accepted: 03/21/2018] [Indexed: 11/23/2022] Open
Abstract
Global introductions of aquatic species and their associated pathogens are threatening worldwide biodiversity. The introduction of two North American crayfish species, Procambarus clarkii and Pacifastacus leniusculus, into Japan in 1927 seems to have negatively affected native Japanese crayfish populations of Cambaroides japonicus. Several studies have shown the decline of these native populations due to competition, predation and habitat colonization by the two invasive North American crayfish species. Here, we identify an additional factor contributing to this decline. We report the first crayfish plague outbreaks in C. japonicus populations in Japan, which were diagnosed using both histological and molecular approaches (analyses of the internal transcribed spacer region). Subsequent analyses of the mitochondrial ribosomal rnnS and rnnL regions of diseased specimens indicate that these outbreaks originated from a P. clarkii population and identify a novel haplotype of Aphanomyces astaci, d3-haplotype, hosted by P. clarkii. Overall, our findings demonstrate the first two cases of crayfish plague in Japan, and the first case in a non-European native crayfish species, which originated from the red swamp crayfish P. clarkii. This finding is a matter of concern for the conservation of the native freshwater species of Japan and also highlights the risk of introducing crayfish carrier species into biogeographic regions harboring species susceptible to the crayfish plague.
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Affiliation(s)
| | - Tadashi Kawai
- Wakanai Fisheries Research Institute, Hokkaido, Japan
| | - Jenny Makkonen
- Department of Environmental and Biological Sciences, University of Eastern Finland, Kuopio, Suomi-Finland
| | - Japo Jussila
- Department of Environmental and Biological Sciences, University of Eastern Finland, Kuopio, Suomi-Finland
| | - Harri Kokko
- Department of Environmental and Biological Sciences, University of Eastern Finland, Kuopio, Suomi-Finland
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MtDNA allows the sensitive detection and haplotyping of the crayfish plague disease agent Aphanomyces astaci showing clues about its origin and migration. Parasitology 2018; 145:1210-1218. [PMID: 29478421 DOI: 10.1017/s0031182018000227] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
The oomycete Aphanomyces astaci, the causative agent of crayfish plague, is listed as one of the 100 worst invasive species in the world, destroying the native crayfish populations throughout Eurasia. The aim of this study was to examine the potential of selected mitochondrial (mt) genes to track the diversity of the crayfish plague pathogen A. astaci. Two sets of primers were developed to amplify the mtDNA of ribosomal rnnS and rnnL subunits. We confirmed two main lineages, with four different haplogroups and five haplotypes among 27 studied A. astaci strains. The haplogroups detected were (1) the A-haplogroup with the a-haplotype strains originating from Orconectes sp., Pacifastacus leniusculus and Astacus astacus; (2) the B-haplogroup with the b-haplotype strains originating from the P. leniusculus; (3) the D-haplogroup with the d1 and d2-haplotypes strains originating from Procambarus clarkii; and (4) the E-haplogroup with the e-haplotype strains originating from the Orconectes limosus. The described markers are stable and reliable and the results are easily repeatable in different laboratories. The present method has high applicability as it allows the detection and characterization of the A. astaci haplotype in acute disease outbreaks in the wild, directly from the infected crayfish tissue samples.
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Majeed M, Kumar G, Schlosser S, El-Matbouli M, Saleh M. In vitro investigations on extracellular proteins secreted by Aphanomyces invadans, the causative agent of epizootic ulcerative syndrome. Acta Vet Scand 2017; 59:78. [PMID: 29121973 PMCID: PMC5680770 DOI: 10.1186/s13028-017-0347-3] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2017] [Accepted: 11/03/2017] [Indexed: 01/10/2023] Open
Abstract
BACKGROUND Proteases produced by many microorganisms, including oomycetes, are crucial for their growth and development. They may also play a critical role in disease manifestation. Epizootic ulcerative syndrome is one of the most destructive fish diseases known. It is caused by the oomycete Aphanomyces invadans and leads to mass mortalities of cultured and wild fish in many countries. The areas of concern are Australia, China, Japan, South and Southeast Asian countries and the USA. Extracellular proteases produced by this oomycete are believed to trigger EUS pathogenesis in fish. To address this activity, we collected the extracellular products (ECP) of A. invadans and identified the secreted proteins using SDS-PAGE and mass spectrometery. A. invadans was cultivated in liquid Glucose-Peptone-Yeats media. The culture media was ultra-filtered through 10 kDa filters and analysed using SDS-PAGE. Three prominent protein bands from the SDS gel were excised and identified by mass spectrometery. Furthermore, we assessed their proteolytic effect on casein and immunoglobulin M (IgM) of rainbow trout (Oncorhynchus mykiss) and giant gourami (Osphronemus goramy). Antiprotease activity of the fish serum was also investigated. RESULTS BLASTp analysis revealed that the prominent secreted proteins were proteases, mainly of the serine and cysteine types. Proteins containing fascin-like domain and bromodomain were also identified. We could demonstrate that the secreted proteases showed proteolytic activity against the casein and the IgM of both fish species. The anti-protease activity experiment showed that the percent inhibition of the common carp serum was 94.2% while that of rainbow trout and giant gourami serum was 7.7 and 12.9%, respectively. CONCLUSIONS The identified proteases, especially serine proteases, could be the potential virulence factors in A. invadans and, hence, are candidates for further functional and host-pathogen interaction studies. The role of identified structural proteins in A. invadans also needs to be investigated further.
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Martín-Torrijos L, Campos Llach M, Pou-Rovira Q, Diéguez-Uribeondo J. Resistance to the crayfish plague, Aphanomyces astaci (Oomycota) in the endangered freshwater crayfish species, Austropotamobius pallipes. PLoS One 2017; 12:e0181226. [PMID: 28750039 PMCID: PMC5531651 DOI: 10.1371/journal.pone.0181226] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2017] [Accepted: 06/28/2017] [Indexed: 11/18/2022] Open
Abstract
The pathogen Aphanomyces astaci Schikora 1906 is responsible for the decline of the native crayfish species of Europe, and their current endangered status. This pathogenic species is native to North America and only colonizes aquatic decapods. The North American crayfish species have a high resistance to this pathogen, while species from other regions are highly susceptible. However, recent field and laboratory observations indicate that there might exist some populations with resistance against this disease. The objective of this study was to test the susceptibility of 8 selected native European crayfish populations of Austropotamobius pallipes Lereboullet 1858 from the Pyrenees. We challenged them against the genome sequenced strain AP03 of A. astaci isolated from a North American red swamp crayfish, Procambarus clarkii Girard 1852, in the Garrotxa Natural Park, Girona. The results showed that there are significant differences (P<0,001) among populations, although most of them show high mortality rates after the zoospore challenge with A. astaci. However, one population from Girona exhibited a 100% survival during a four-month monitoring period under the experimental conditions tested. Histological analyses revealed a high immune reaction in tissues examined, i.e., encapsulation and melanization of hyphae, similar to that found in North American resistant crayfish species. These results represent the first observation of a native European crayfish population showing high resistance towards the most virulent genotype of this pathogen, i.e., genotype Pc. The identification of this population is of key importance for the management of these endangered species, and represents a crucial step forward towards the elucidation of the factors involved in the immune reaction against this devastating pathogen.
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Affiliation(s)
- Laura Martín-Torrijos
- Department of Mycology, Real Jardín Botánico (RJB-CSIC), Plaza Murillo, 2, Madrid, Spain
| | | | - Quim Pou-Rovira
- Consorci del´Estany, Plaça dels estudis, 2, Banyoles, Girona, Spain
| | - Javier Diéguez-Uribeondo
- Department of Mycology, Real Jardín Botánico (RJB-CSIC), Plaza Murillo, 2, Madrid, Spain
- * E-mail:
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