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Phage-mediated Delivery of Targeted sRNA Constructs to Knock Down Gene Expression in E. coli
Published on: March 20, 2016
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Targeting multidrug-resistant bacteria with genetic-information-free protein-only phages.
Jeanette Batres1, Branden Hunter1, Hyunjin Shim1
1Department of Biology, California State University, Fresno, 5241 N Maple Ave, Fresno, CA 93740, USA.
Biorxiv : the Preprint Server for Biology
|November 24, 2025
Summary
Protein-only phages (POPs) are genome-free particles that deliver antimicrobial proteins into bacteria. This approach offers phage specificity with reduced risks, advancing phage-inspired therapeutics.
Area of Science:
- Microbiology
- Biotechnology
- Protein Engineering
Background:
- Bacteriophages offer targeted bacterial killing but their replication poses risks.
- Genetic-information-free, protein-only phages (POPs) are engineered to retain phage benefits while eliminating replication.
- POPs leverage phage structure for targeted delivery of antimicrobial proteins.
Purpose of the Study:
- To test the hypothesis that POPs can stochastically encapsulate and deliver antimicrobial proteins into bacteria.
- To evaluate the antimicrobial efficacy and safety profile of POPs.
Main Methods:
- Engineered protein-only phages (POPs) using a cell-free protein synthesis system.
- Computational analysis of phage T7 genome for suitable small proteins.
- Antimicrobial susceptibility assays to assess POPs' efficacy over 48-72 hours.
Main Results:
- POPs self-assemble from de novo gene fragments encoding structural and antimicrobial proteins.
- Computational survey identified suitable small proteins and sufficient capsid volume in T7 POPs.
- Antimicrobial assays showed POPs achieved growth inhibition comparable to wild-type T7, with a dose-effect relationship.
Conclusions:
- Demonstrated the feasibility of genetic-information-free POPs as a novel protein-based antimicrobial strategy.
- POPs combine phage receptor specificity with enhanced biosafety and predictability.
- Supports the development of stable and predictable phage-inspired therapeutics.
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