Systematic strategies for developing phage resistant Escherichia coli strains.

Area of Science:

• Microbiology and Biotechnology
• Bacteriophage Research
• Genetic Engineering

Background:

• Bacteriophages (phages) are significant threats to bacterial cultures in industrial fermentation.
• Existing bacterial defenses against phages are often narrow-spectrum and insufficient.
• Phage contamination can lead to significant losses in bioproduction.

Purpose of the Study:

• To develop robust, phage-resistant Escherichia coli strains for industrial applications.
• To enhance bacterial resilience against diverse phage infections.
• To maintain the productivity of engineered strains under phage challenge.

Main Methods:

• Genomic integration of a DNA phosphorothioation-based Ssp defense module into E. coli.
• Introduction of mutations in essential phage life cycle components.
• Testing engineered E. coli resistance against a panel of diverse phages.
• Assessing the impact of phage resistance on cell growth and recombinant protein production.

Main Results:

• Engineered E. coli strains exhibited strong resistance to a wide range of tested phages.
• The developed phage resistance did not negatively affect bacterial cell growth.
• Engineered strains successfully produced recombinant proteins (D-amino acid oxidase, nsp8) under phage cocktail challenge.

Conclusions:

• Simultaneous genomic modification provides effective, broad-spectrum phage resistance in E. coli.
• This strategy enables the development of robust bacterial strains for industrial fermentation.
• The engineered strains maintain high productivity, crucial for biopharmaceutical and chemical production.