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A Protein Microarray Assay for Serological Determination of Antigen-specific Antibody Responses Following Clostridium difficile Infection
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Small-Molecule Allosteric Triggers of Clostridium difficile Toxin B Auto-proteolysis as a Therapeutic Strategy

Mattias E Ivarsson1, Estelle Durantie1, Corina Huberli1

  • 1Institute of Pharmaceutical Sciences, Department of Chemistry and Applied Biosciences, ETH Zurich, Vladimir-Prelog-Weg 1-5/10, Zurich 8093, Switzerland.

Cell Chemical Biology
|November 29, 2018
PubMed

Insights

Researchers developed novel inositol hexakisphosphate (IP6) analogs to inactivate Clostridium difficile toxin B (TcdB). Oral administration of these IP6 analogs attenuated inflammation and improved survival in mouse models of C. difficile infection (CDI).

Area of Science:

  • Microbiology
  • Biochemistry
  • Pharmacology

Background:

  • Clostridium difficile infection (CDI) presents a growing threat, with symptoms driven by potent protein toxins.
  • The virulence of C. difficile toxins, such as toxin B (TcdB), is regulated by intracellular auto-proteolysis, activated by inositol hexakisphosphate (IP6).

Purpose of the Study:

  • To investigate the potential of small molecules to trigger TcdB auto-proteolysis in the gut lumen, thereby inactivating the toxin before cellular uptake.
  • To design IP6 analogs resistant to calcium chelation in the gut, enabling sustained allosteric activation of TcdB.

Main Methods:

  • Development of novel inositol hexakisphosphate (IP6) analogs with reduced calcium-binding affinity.
  • Assessment of the allosteric activity of IP6 analogs at physiological calcium concentrations.
  • Evaluation of the therapeutic efficacy of oral IP6 analog administration in mouse models of C. difficile infection (CDI).

Main Results:

  • The designed IP6 analogs retained allosteric activity in the presence of physiological calcium concentrations.
  • Oral administration of IP6 analogs significantly attenuated inflammation in CDI mouse models.
  • Treatment with IP6 analogs promoted enhanced survival rates in mice challenged with C. difficile.

Conclusions:

  • Small-molecule allosteric triggers, specifically modified IP6 analogs, represent a promising therapeutic strategy for C. difficile infection (CDI).
  • This approach targets toxin auto-proteolysis in the gut lumen, offering a novel mechanism to combat CDI pathogenesis.
Keywords:
Clostridium difficileallosteric modulatorbacterial toxinsinositol phosphatenon-antibiotic strategysmall-molecule drug

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