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High-throughput Assay to Phenotype Salmonella enterica Typhimurium Association, Invasion, and Replication in Macrophages
Published on: August 11, 2014
Stapled Phd Peptides Inhibit Doc Toxin Induced Growth Arrest in Salmonella
Dennis J Worm1, Grzegorz J Grabe2, Guilherme V de Castro1
1Department of Chemistry, Molecular Sciences Research Hub, Imperial College London, 82 Wood Lane, London W12 0BZ, U.K.
Abstract:
Bacterial toxin inhibition is a promising approach to overcoming antibiotic failure. InSalmonella, knockout of the toxin Doc has been shown to significantly reduce the formation of antibiotic-tolerant persisters. Doc is a kinase that is inhibited in nontolerant cells by its cognate antitoxin, Phd. In this work, we have developed first-in-class stapled peptide antitoxin mimetics based on the Doc inhibitory sequence of Phd. After making a series of substitutions to improve bacterial uptake, we identified a lead stapled Phd peptide that is able to counteract Doc toxicity in Salmonella. This provides an exciting starting point for the further development of therapeutic peptides capable of reducing antibiotic persistence in pathogenic bacteria.
Insights
Researchers developed novel stapled peptide antitoxins to inhibit bacterial toxins, reducing antibiotic persistence in Salmonella. This breakthrough offers a new strategy against antibiotic failure.
Area of Science:
- Microbiology
- Molecular Biology
- Drug Discovery
Background:
- Antibiotic resistance is a growing global health threat, necessitating novel therapeutic strategies.
- Bacterial persister cells contribute to antibiotic treatment failure by exhibiting tolerance to antimicrobial agents.
- The Doc toxin in Salmonella plays a role in the formation of antibiotic-tolerant persister cells.
Purpose of the Study:
- To develop novel therapeutic agents targeting bacterial toxins.
- To create first-in-class stapled peptide antitoxin mimetics based on the Phd antitoxin sequence.
- To evaluate the efficacy of these peptide mimetics in counteracting Doc toxicity and reducing antibiotic persistence in Salmonella.
Main Methods:
- Design and synthesis of stapled peptide mimetics based on the Phd antitoxin.
- Introduction of substitutions to enhance bacterial uptake of the peptides.
- In vitro and in vivo assays to assess the inhibition of Doc toxicity in Salmonella.
- Evaluation of the impact of the lead peptide on antibiotic persistence.
Main Results:
- Successful development of first-in-class stapled peptide antitoxin mimetics.
- Identification of a lead stapled Phd peptide with improved bacterial uptake.
- Demonstration that the lead peptide effectively counteracts Doc toxicity in Salmonella.
- Evidence suggesting the potential of this approach to reduce antibiotic persistence.
Conclusions:
- Stapled peptide antitoxin mimetics represent a promising new class of therapeutics.
- The developed Phd-based stapled peptide is a viable starting point for combating antibiotic persistence.
- This research opens avenues for developing novel peptide-based strategies against pathogenic bacteria and antibiotic failure.
