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Updated: Feb 13, 2026
12:58
A Protocol to Characterize the Morphological Changes of Clostridium difficile in Response to Antibiotic Treatment
Published on: May 25, 2017
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Pleiotropic roles of Clostridium difficile sin locus.
Brintha Parasumanna Girinathan1, Junjun Ou2, Bruno Dupuy3,4
1Division of Biology, Kansas State University, Manhattan, KS, United Sates of America.
Plos Pathogens
|March 13, 2018
Summary
The sin locus in Clostridium difficile regulates sporulation, toxin production, and motility, crucial for infection. SinR acts as a repressor, while SinR
Area of Science:
- Microbiology
- Molecular Biology
- Pathogenesis
Background:
- Clostridium difficile causes nosocomial diarrhea and colitis, with spores enabling transmission and environmental persistence.
- The sin locus in Bacillus subtilis regulates sporulation inhibition via SinR repressor and SinI inhibitor.
- C. difficile possesses two sinR homologs, sinR and sinR', within an operon.
Purpose of the Study:
- To investigate the role of the sin locus in C. difficile physiology and pathogenesis.
- To elucidate the regulatory functions of SinR and SinR' in C. difficile.
Main Methods:
- Construction and characterization of sin locus mutants in C. difficile strains R20291 and JIR8094.
- Transcriptome analysis of sinRR' mutants.
- Genetic and biochemical experiments, including a hamster infection model.
Main Results:
- Sin locus mutants exhibit pleiotropic effects on sporulation, toxin production, and motility.
- SinR regulates key transcriptional regulators: sigD, spo0A, and codY.
- SinR' antagonizes SinR's repressor activity; the sin locus is essential for C. difficile infection in hamsters.
Conclusions:
- The C. difficile sin locus is a central regulator connecting sporulation, toxin production, and motility networks.
- This locus plays a critical role in C. difficile pathogenesis.
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