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In Vitro Directed Evolution of a Restriction Endonuclease with More Stringent Specificity
Published on: March 25, 2020
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Directed Evolution of Replication-Competent Double-Stranded DNA Bacteriophage toward New Host Specificity
Jing Liang1, Huibin Zhang2, Yee Ling Tan1
1Strain Engineering, Singapore Institute of Food and Biotechnology Innovation, Singapore 138669, Singapore.
ACS Synthetic Biology
|January 28, 2022
Summary
Bacteriophages offer a promising alternative to antibiotics for combating antimicrobial resistance. This study engineered T7 bacteriophage variants with altered host specificity, demonstrating potential for broader therapeutic applications.
Area of Science:
- Microbiology
- Molecular Biology
- Biotechnology
Background:
- Antimicrobial resistance necessitates novel therapeutic strategies.
- Bacteriophages (phages) show promise as alternatives to antibiotics.
- Phage therapy requires specific host-bacteriophage matching due to narrow host ranges.
Purpose of the Study:
- To engineer bacteriophage specificity and improve therapeutic qualities.
- To develop a method for generating large libraries of phage variants with diverse host specificities.
- To explore directed evolution for enhancing phage characteristics beyond natural selection.
Main Methods:
- Utilized directed evolution to create large libraries of replication-competent phage variants from synthetic DNA.
- Generated a library of over 10^7 T7 bacteriophage tail fiber mutants.
- Screened mutant libraries for altered host specificity and improved lytic efficiency.
Main Results:
- Identified T7 phage mutants with broadened host specificity, including lytic activity against *Yersinia enterocolitica*.
- Discovered mutants exhibiting enhanced lytic efficiency and improved tolerance to lytic conditions.
- Observed limitations in altering host specificity solely through tail fiber mutagenesis, suggesting other factors are critical.
Conclusions:
- Directed evolution of bacteriophages is a viable strategy for engineering host specificity and therapeutic traits.
- Tail fiber modification can broaden phage host range, but other genetic elements may also limit specificity.
- This approach holds potential for developing tailored phage therapies to combat antimicrobial resistance.
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