MtDNA allows the sensitive detection and haplotyping of the crayfish plague disease agent Aphanomyces astaci showing clues about its origin and migration

AbstractThe 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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Parasite DNA detection in water samples enhances crayfish plague monitoring in asymptomatic invasive populations

Biological Invasions ◽

10.1007/s10530-021-02644-y ◽

2021 ◽

Author(s):

Natalie Sieber ◽

Hanna Hartikainen ◽

Raphael Krieg ◽

Armin Zenker ◽

Christoph Vorburger

Keyword(s):

Water Samples ◽

Pathogen Detection ◽

Procambarus Clarkii ◽

Limit Of Detection ◽

Disease Outbreaks ◽

Sampling Effort ◽

Tissue Samples ◽

Aphanomyces Astaci ◽

Monitoring Tools ◽

Invasive Crayfish

AbstractInvasive species can facilitate the spread of pathogens by first providing asymptomatic host reservoirs, and then driving disease outbreaks in native populations through pathogen spillover. An example of this are invasive crayfish species in Europe (Faxonius limosus, Pacifastacus leniusculus, Procambarus clarkii), which carry the deadly plague agent (Aphanomyces astaci). Effective disease management requires comprehensive monitoring, however, pathogen detection in carrier populations with low pathogen prevalence and intensities is challenging. We simultaneously collected and analysed crayfish tissue samples of invasive crayfish populations and water samples to compare A. astaci detection in different sample types using quantitative PCR. Combined, the two sampling methods revealed A. astaci presence with DNA concentrations above limit of detection (LOD; the lowest concentration which can be detected with reasonable certainty) in 13 of 23 invasive crayfish populations. In four additional sites, A. astaci DNA concentrations below LOD were found in water. In four populations only were A. astaci concentrations above LOD detected in both sample types and in three populations in concentrations above LOD in tissue but below LOD in water. The likely reason for these discrepancies is the low A. astaci prevalence and concentration in resistant invasive crayfish, which limit detection reliability. Consistency may be improved by timing surveys with seasonal periods of high A. astaci abundance and by increasing water sampling effort. Considering the ease of collecting eDNA samples, compared to crayfish tissue sampling, eDNA methods would facilitate frequent and comprehensive surveys. However, remaining uncertainties in eDNA-based detection reveal the relevance of combining monitoring tools to improve detection of invasive pathogens and their management.

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Coexistence of Two Invasive Species, Procambarus clarkii and Aphanomyces astaci, in Brackish Waters of a Mediterranean Coastal Lagoon

Frontiers in Ecology and Evolution ◽

10.3389/fevo.2020.622434 ◽

2021 ◽

Vol 8 ◽

Author(s):

Laura Martín-Torrijos ◽

Angel Jose Correa-Villalona ◽

Antonio Pradillo ◽

Javier Diéguez-Uribeondo

Keyword(s):

Invasive Species ◽

Coastal Lagoon ◽

Procambarus Clarkii ◽

Freshwater Ecosystems ◽

Freshwater Crayfish ◽

Brackish Waters ◽

Aphanomyces Astaci ◽

Salinity Levels ◽

Native Crayfish ◽

Mediterranean Coastal Lagoon

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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May atyid shrimps act as potential vectors of crayfish plague?

NeoBiota ◽

10.3897/neobiota.51.37718 ◽

2019 ◽

Vol 51 ◽

pp. 65-80 ◽

Cited By ~ 1

Author(s):

Agata Mrugała ◽

Miloš Buřič ◽

Adam Petrusek ◽

Antonín Kouba

Keyword(s):

Procambarus Clarkii ◽

Freshwater Crayfish ◽

Transmission Experiment ◽

Shrimp Species ◽

Aphanomyces Astaci ◽

Freshwater Shrimps ◽

Successful Infection ◽

In The Wild ◽

Species Specific ◽

Crayfish Species

The causative agent of crayfish plague, Aphanomyces astaci Schikora, was long considered to be a specialist pathogen whose host range is limited to freshwater crayfish. Recent studies, however, provided evidence that this parasite does not only grow within the tissues of freshwater-inhabiting crabs but can also be successfully transmitted by them to European crayfish species. The potential to act as alternative A. astaci hosts was also indicated for freshwater shrimps. We experimentally tested resistance of two freshwater atyid shrimps: Atyopsis moluccensis (De Haan, 1849) and Atya gabonensis Giebel, 1875. They were infected with the A. astaci strain associated with the globally widespread North American red swamp crayfish, Procambarus clarkii (Girard, 1852), the typical host of the A. astaci genotype group D. As popular ornamental species, both shrimps may get in contact with infected P. clarkii not only in the wild but also in the aquarium trade. We assessed the potential of shrimps to transmit A. astaci to susceptible crayfish by cohabiting A. gabonensis previously exposed to A. astaci zoospores with the European noble crayfish, Astacus astacus (Linnaeus, 1758). In both experiments, the presence of A. astaci infection was analysed with species-specific quantitative PCR. We detected A. astaci in bodies and exuviae of both shrimp species exposed to A. astaci zoospores, however, the intensity of infection differed between the species and analysed samples; it was higher in A. moluccensis and the exuviae of both species. A. astaci was also detected in one A. astacus individual in the transmission experiment. This finding reveals that freshwater shrimps may be able to transmit A. astaci to crayfish hosts; this is particularly important as even a single successful infection contributes to the spread of the disease. Moreover, our results indicate that the tested shrimp species may be capable of resisting A. astaci infection and reducing its intensity through moulting. Although their potential to act as prominent A. astaci vectors requires further research, it should not be ignored as these freshwater animals may then facilitate A. astaci spread to susceptible crayfish species in aquarium and aquaculture facilities as well as in the wild.

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Money Kills Native Ecosystems: European Crayfish as an Example

Frontiers in Ecology and Evolution ◽

10.3389/fevo.2021.648495 ◽

2021 ◽

Vol 9 ◽

Author(s):

Japo Jussila ◽

Lennart Edsman ◽

Ivana Maguire ◽

Javier Diéguez-Uribeondo ◽

Kathrin Theissinger

Keyword(s):

Alien Species ◽

Aquatic Ecosystems ◽

Significant Proportion ◽

Suitable Habitat ◽

Freshwater Crayfish ◽

Aphanomyces Astaci ◽

Commercial Activities ◽

Disease Agent ◽

Native Crayfish ◽

Crayfish Species

Native European crayfish conservation was triggered by invasion of crayfish plague disease agent, Aphanomyces astaci, starting 1860s in Northern Italy. Resulting crayfish plague epidemics quickly spread over Continental Europe, then to Finland, Sweden and finally, after running amok around Europe, A. astaci was discovered also in Iberian Peninsula, Norway, Ireland, and United Kingdom in 1970s and 1980s. By that time significant proportion of native crayfish stocks had been lost, and while crayfish plague epidemics were still recorded, also industrialization and waterways construction were causing damage to remaining native crayfish stocks. While alien crayfish introductions, at least Faxonius limosus, already gave rise to first wave of crayfish plague epidemics in late 19th century, later in 1960s it was decided that introductions of alien Pacifastacus leniusculus should be initiated to replace native European crayfish populations. Decisions were based on presumed advantages for fishery, suitable habitat requirements and supposed immunity against A. astaci. Furthermore, conservation of native European crayfish species was sidelined and focus shifted toward alien crayfish stocking routine and consumption. Alien crayfish species introductions resulted in repeated waves of crayfish plague epidemics among remaining native crayfish stocks. It was soon discovered that alien crayfish of North American origin were, as suspected, permanent reservoirs for A. astaci, that some of those alien species were losing their resistance against selected strains of A. astaci and struggled in European aquatic ecosystems. In this article, we introduce numerous motives behind grand mistake of introducing alien crayfish species to Europe and then promoting their stocks instead of focusing on conservation of native crayfish species. We outline how false economical, biological and ecologic assumptions were used to justify a hasty introduction of alien crayfish, which has further devastated native crayfish and also permanently changed European aquatic ecosystems, both with disastrous consequences. Lesson to be learnt is that science-based warnings about alien species damage to native ecosystems and native crayfish must be taken with utmost caution. Protection of native European crayfish should be core issue, not commercial activities. Finally, we summarize main threats and actions needed to protect remaining native freshwater crayfish fauna in Europe.

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Optimization and Physicochemical Characterization of Chitosan and Chitosan Nanoparticles Extracted from the Crayfish Procambarus clarkii Wastes

Journal of Shellfish Research ◽

10.2983/035.038.0220 ◽

2019 ◽

Vol 38 (2) ◽

pp. 385 ◽

Cited By ~ 3

Author(s):

Marwa M. El-Naggar ◽

Wael S. I. Abou-Elmagd ◽

Ashraf Suloma ◽

Hamza A. El-Shabaka ◽

Magdy T. Khalil ◽

...

Keyword(s):

Procambarus Clarkii ◽

Chitosan Nanoparticles ◽

Physicochemical Characterization

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Circular RNA hsa_circ_0006401 promotes proliferation and metastasis in colorectal carcinoma

Cell Death and Disease ◽

10.1038/s41419-021-03714-8 ◽

2021 ◽

Vol 12 (5) ◽

Author(s):

Chenjing Zhang ◽

Xiaolu Zhou ◽

Xiaoge Geng ◽

Yu Zhang ◽

Jingya Wang ◽

...

Keyword(s):

Splice Junction ◽

Circular Rna ◽

Host Gene ◽

Cell Counting ◽

Tissue Samples ◽

Proliferation And Metastasis ◽

And Migration ◽

Proliferation And Migration

AbstractDysregulation of circular RNA (circRNA) expression is involved in the progression of cancer. Here, we aimed to study the potential function of hsa_circ_0006401 in colorectal cancer (CRC). CircRNA hsa_circ_0006401 expression levels in CRC and adjacent nontumor tissues were analyzed by real-time quantitative PCR (qRT-PCR) and circRNA in situ hybridization (RNA-ISH). Then, CRC cell proliferation was assessed by cell counting. Wound-healing and transwell assays were utilized to detect the effect of hsa_circ_0006401 on CRC migration. A circRNA-ORF construct was created, and a specific antibody against the splice junction of hsa_circ_0006401 was prepared. Finally, the proteins directly binding to hsa_circ_0006401 peptides were identified by immunoprecipitation combined with mass spectrometry. In our study, we found hsa_circ_0006401 was closely related to CRC metastasis and exhibited upregulated expression in metastatic CRC tissue samples. Proliferation and migration were inhibited in vitro when hsa_circ_0006401 expression was silenced. Downregulation of hsa_circ_0006401 expression decreased CRC proliferation and liver metastasis in vivo. A 198-aa peptide was encoded by sequences of the splice junction absent from col6a3. Hsa_circ_0006401 promoted CRC proliferation and migration by encoding the hsa_circ_0006401 peptide. Hsa_circ_0006401 peptides decreased the mRNA and protein level of the host gene col6a3 by promoting col6a3 mRNA stabilation. In conclusion, our study revealed that circRNAs generated from col6a3 that contain an open-reading frame (ORF) encode a novel 198-aa functional peptide and hsa_circ_0006401 peptides promote stability of the host gene col6a3 mRNA to promote CRC proliferation and metastasis.

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Severe acute respiratory syndrome (SARS) related coronavirus in bats

Animal Diseases ◽

10.1186/s44149-021-00004-w ◽

2021 ◽

Vol 1 (1) ◽

Author(s):

Rong Geng ◽

Peng Zhou

Keyword(s):

Severe Acute Respiratory Syndrome ◽

Current Knowledge ◽

Disease Outbreaks ◽

First Century ◽

Intermediate Hosts ◽

Human Coronavirus ◽

Transmission Potential ◽

Disease Agent ◽

And Control ◽

Genomic Similarity

AbstractThree major human coronavirus disease outbreaks, severe acute respiratory syndrome (SARS), Middle East respiratory syndrome (MERS) and 2019 coronavirus disease (COVID-19), occurred in the twenty-first century and were caused by different coronaviruses (CoVs). All these viruses are considered to have originated from bats and transmitted to humans through intermediate hosts. SARS-CoV-1 and SARS-CoV-2, disease agent of COVID-19, shared around 80% genomic similarity, and thus belong to SARS-related CoVs. As a natural reservoir of viruses, bats harbor numerous other SARS-related CoVs that could potentially infect humans around the world, causing SARS or COVID-19 like outbreaks in the future. In this review, we summarized the current knowledge of CoVs on geographical distribution, genetic diversity, cross-species transmission potential and possible pathogenesis in humans, aiming for a better understanding of bat SARS-related CoVs in the context of prevention and control.

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Characterization of Enterococcus faecium mutants resistant to mundticin KS, a class IIa bacteriocin

Microbiology ◽

10.1099/mic.0.26435-0 ◽

2003 ◽

Vol 149 (10) ◽

pp. 2901-2908 ◽

Cited By ~ 26

Author(s):

Youko Sakayori ◽

Mizuho Muramatsu ◽

Satoshi Hanada ◽

Yoichi Kamagata ◽

Shinichi Kawamoto ◽

...

Keyword(s):

Enterococcus Faecium ◽

Antimicrobial Agents ◽

Wild Type Strain ◽

Unsaturated Fatty Acids ◽

Class I ◽

Wild Type ◽

Food Preservatives ◽

In The Wild ◽

Resistant Mutants

The emergence and spread of mutants resistant to bacteriocins would threaten the safety of using bacteriocins as food preservatives. To determine the physiological characteristics of resistant mutants, mutants of Enterococcus faecium resistant to mundticin KS, a class IIa bacteriocin, were isolated. Two types of mutant were found that had different sensitivities to other antimicrobial agents such as nisin (class I) and kanamycin. Both mutants were resistant to mundticin KS even in the absence of Mg2+ ions. The composition of unsaturated fatty acids in the resistant mutants was significantly increased in the presence of mundticin KS. The composition of the phospholipids in the two resistant mutants also differed from those in the wild-type strain. The putative zwitterionic amino-containing phospholipid in both mutants significantly increased, whereas amounts of phosphatidylglycerol and cardiolipin decreased. These changes in membrane structure may influence resistance of enterococci to class IIa and class I bacteriocins.

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