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Enrichment and Detection of Clostridium perfringens Toxinotypes in Retail Food Samples
Published on: October 18, 2019
Clostridium perfringens: insight into virulence evolution and population structure
Youhanna S Sawires1, J Glenn Songer
1Department of Veterinary Science and Microbiology, University of Arizona, Room 207, 1117 East Lowell Street, Tucson AZ 85721, USA. sawiresy@email.arizona.edu
Anaerobe
|May 17, 2006
Summary
Clostridium perfringens virulence factors evolve through recent gene acquisition and recombination, enabling adaptation to diverse hosts. Understanding its dynamic population structure is key to controlling diseases.
Area of Science:
- Microbiology
- Evolutionary Biology
- Genetics
Background:
- Clostridium perfringens is a significant pathogen causing life-threatening diseases in veterinary and medical fields.
- Its virulence mechanisms and the distribution of toxin genes within its population are not fully understood.
- The bacterium is also a normal inhabitant of the intestinal tract in humans and animals.
Purpose of the Study:
- To investigate the population structure and evolution of virulence in Clostridium perfringens.
- To understand the acquisition and maintenance of toxin/enzyme genes.
- To explore the factors contributing to the bacterium's ability to cause disease across different hosts.
Main Methods:
- Multiple-locus variable-number tandem repeat analysis (MLVA) was employed to study the population genetics.
- Phylogenetic analysis was used to examine the evolutionary history of toxin genes.
- Population structure was analyzed to identify recombination and clonal expansion events.
Main Results:
- Acquisition of major toxin genes appears to be a recent evolutionary event, driven by selective advantages in specific niches.
- Virulent strains demonstrate the ability to cause disease in various host species, with some normal flora strains becoming virulent in new hosts.
- Recombination is a primary driver of population structure, interspersed with clonal expansions linked to disease outbreaks.
- Positive selection was detected in the alpha toxin gene, suggesting adaptive evolution.
Conclusions:
- Clostridium perfringens exhibits a dynamic population structure shaped by recombination and clonal expansions.
- The evolution of virulence is linked to the acquisition of toxin genes and adaptation to different hosts.
- Further research using genomics, proteomics, and animal models is needed to fully elucidate C. perfringens virulence.
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