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Detecting Cortex Fragments During Bacterial Spore Germination
Published on: June 25, 2016
Functional characterization of Clostridium difficile spore coat proteins
Patima Permpoonpattana1, Jutarop Phetcharaburanin, Anna Mikelsone
1School of Biological Sciences, Royal Holloway, University of London, Egham, Surrey, United Kingdom.
Journal of Bacteriology
|January 22, 2013
Summary
Clostridium difficile spore coat proteins were studied using ClosTron mutagenesis. CotA is crucial for spore coat assembly, while other proteins like CotD, SodA, and CotE possess enzymatic activity important for spore function.
Area of Science:
- Microbiology
- Molecular Biology
- Structural Biology
Background:
- Clostridium difficile is a significant human pathogen.
- Spore dissemination is key to C. difficile spread.
- Functional characteristics of C. difficile spores were previously unknown.
Purpose of the Study:
- To investigate the role of specific spore coat proteins in C. difficile.
- To understand the structural and functional contribution of spore coat genes.
- To identify enzymatic activities present on the C. difficile spore surface.
Main Methods:
- ClosTron insertional mutagenesis was used to disrupt six spore coat genes (cotA, cotB, cotCB, cotD, cotE, sodA).
- Spore assembly and integrity were analyzed.
- Enzyme activity of recombinant proteins was confirmed in vitro.
- Protein localization (CotF, CotG) was determined.
Main Results:
- Mutation of cotA caused major structural defects in spore coat assembly.
- Mutation of cotD, cotE, and sodA reduced or abolished enzyme activity but not spore integrity.
- CotD (manganese catalase), SodA (superoxide dismutase), and CotE (peroxiredoxin-chitinase) were confirmed as enzymes.
- CotF and CotG were localized to the spore surface.
Conclusions:
- CotA is essential for stabilizing the C. difficile spore coat.
- Surface-exposed enzymes (CotD, SodA, CotE) likely contribute to spore coat polymerization and detoxification.
- The exosporium may contain redundant structural elements or house these enzymatic proteins.
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