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Home / Equine Research Bank / PLoS One / A novel pore-forming toxin in type A Clostridium perfringens...
PloS one2015; 10(4); e0122684; doi: 10.1371/journal.pone.0122684

A novel pore-forming toxin in type A Clostridium perfringens is associated with both fatal canine hemorrhagic gastroenteritis and fatal foal necrotizing enterocolitis.

Abstract: A role for type A Clostridium perfringens in acute hemorrhagic and necrotizing gastroenteritis in dogs and in necrotizing enterocolitis of neonatal foals has long been suspected but incompletely characterized. The supernatants of an isolate made from a dog and from a foal that died from these diseases were both found to be highly cytotoxic for an equine ovarian (EO) cell line. Partial genome sequencing of the canine isolate revealed three novel putative toxin genes encoding proteins related to the pore-forming Leukocidin/Hemolysin Superfamily; these were designated netE, netF, and netG. netE and netF were located on one large conjugative plasmid, and netG was located with a cpe enterotoxin gene on a second large conjugative plasmid. Mutation and complementation showed that only netF was associated with the cytotoxicity. Although netE and netG were not associated with cytotoxicity, immunoblotting with specific antisera showed these proteins to be expressed in vitro. There was a highly significant association between the presence of netF with type A strains isolated from cases of canine acute hemorrhagic gastroenteritis and foal necrotizing enterocolitis. netE and netF were found in all cytotoxic isolates, as was cpe, but netG was less consistently present. Pulsed-field gel electrophoresis showed that netF-positive isolates belonged to a clonal population; some canine and equine netF-positive isolates were genetically indistinguishable. Equine antisera to recombinant Net proteins showed that only antiserum to rNetF had high supernatant cytotoxin neutralizing activity. The identifica-tion of this novel necrotizing toxin is an important advance in understanding the virulence of type A C. perfringens in specific enteric disease of animals.
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Publication Date: 2015-04-08 PubMed ID: 25853427PubMed Central: PMC4390311DOI: 10.1371/journal.pone.0122684Google Scholar: Lookup
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Summary

This research summary has been generated with artificial intelligence and may contain errors and omissions. Refer to the original study to confirm details provided. Submit correction.

The research investigation centers on the role of a particular bacterium, type A Clostridium perfringens, in severe intestinal diseases in dogs and foals. The study specifically brings forth some explicitly novel toxin genes that might be crucial determinants in the pathogenesis and virulence of these diseases.

Objective of the Study

  • The study was conducted to explore the role of type A Clostridium perfringens, a species of bacteria, in triggering lethal gastrointestinal diseases in dogs and foals. Specifically, the focus was to identify and characterize possible toxin genes associated with the pathogenesis and virulence of these illnesses.

Methodology and Preliminary Observations

  • An isolate of the bacterium from a dog and a foal that succumbed to these diseases proved to be highly cytotoxic to an equine ovarian (EO) cell line.
  • Partial genome sequencing of the isolate from the dog identified three new potential toxin genes encoding proteins from the Leukocidin/Hemolysin Superfamily. These were named netE, netF, and netG.
  • These genes were located on large conjugative plasmids – DNA molecules separately existing from chromosomal DNA and capable of self-replication.
  • Following mutation and complementation studies, only netF was found to be associated with the observed cytotoxicity.

Association with Diseases and Cytotoxicity

  • Despite netE and netG not being linked to cytotoxicity, they were expressed in vitro according to immunoblotting tests using specific antisera.
  • A strong correlation was noted between the presence of the netF gene and type A C. perfringens strains found in cases of canine hemorrhagic gastroenteritis and foal necrotizing enterocolitis.
  • Among all the cytotoxic isolates tested, cpe, netE and netF were uniformly present, while netG presence was inconsistent.

Genetic Similarities and Neutralizing Activity

  • Pulsed-field gel electrophoresis revealed that netF-positive isolates were a clonal population — they derived from the same parent and were essentially genetically identical.
  • There were certain canine and equine isolates bearing the netF gene that were indistinguishable genetically.
  • Equine antisera tests against recombinant Net proteins demonstrated that only the antiserum versus rNetF had potent supernatant cytotoxin neutralizing activity.

Significance of Findings

  • The identification of this new necrotizing toxin signifies an important step in understanding the virulence of type A C. perfringens in specific enteric diseases of animals, promising opportunities for more targeted therapeutic strategies.

Cite This Article

APA
Mehdizadeh Gohari I, Parreira VR, Nowell VJ, Nicholson VM, Oliphant K, Prescott JF. (2015). A novel pore-forming toxin in type A Clostridium perfringens is associated with both fatal canine hemorrhagic gastroenteritis and fatal foal necrotizing enterocolitis. PLoS One, 10(4), e0122684. https://doi.org/10.1371/journal.pone.0122684

Publication

PloS one
ISSN: 1932-6203
NlmUniqueID: 101285081
Country: United States
Language: English
Volume: 10
Issue: 4
Pages: e0122684

Researcher Affiliations

Mehdizadeh Gohari, Iman
  • Department of Pathobiology, University of Guelph, Guelph, Ontario, Canada.
Parreira, Valeria R
  • Department of Pathobiology, University of Guelph, Guelph, Ontario, Canada.
Nowell, Victoria J
  • Department of Pathobiology, University of Guelph, Guelph, Ontario, Canada.
Nicholson, Vivian M
  • Department of Pathobiology, University of Guelph, Guelph, Ontario, Canada.
Oliphant, Kaitlyn
  • Department of Pathobiology, University of Guelph, Guelph, Ontario, Canada.
Prescott, John F
  • Department of Pathobiology, University of Guelph, Guelph, Ontario, Canada.

MeSH Terms

  • Animals
  • Bacterial Toxins / chemistry
  • Bacterial Toxins / genetics
  • Bacterial Toxins / pharmacology
  • Cell Line / drug effects
  • Clostridium perfringens / genetics
  • Clostridium perfringens / pathogenicity
  • Dogs
  • Enterocolitis, Necrotizing / genetics
  • Enterocolitis, Necrotizing / microbiology
  • Enterocolitis, Necrotizing / veterinary
  • Enterotoxins / genetics
  • Enterotoxins / pharmacology
  • Gastroenteritis / genetics
  • Gastroenteritis / microbiology
  • Gastroenteritis / veterinary
  • Genome
  • High-Throughput Nucleotide Sequencing
  • Horses
  • Nuclear Pore / drug effects

Conflict of Interest Statement

Competing Interests: The authors have declared that no competing interests exist.

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