Phage Therapy for Bioreactor Control
A recent podcast explored industrial phage therapy as a precision tool for managing microbial contamination in bioreactors. This approach uses specific viruses (phages) to target and eliminate harmful microbes without affecting desired production strains. Experts suggest the technology is poised to become a critical method for reducing costly downtime in biomanufacturing.
- Phage contamination has been a known threat in industrial fermentation for nearly a century, first identified as a cause of failure in dairy product fermentation in 1935 and later documented as a major problem in the industrial acetone-butanol fermentation processes of the early 20th century. - The primary advantage over chemical biocides or antibiotics is specificity; phages can target a single bacterial strain without affecting the diverse and beneficial microbial communities essential for the fermentation process. This precision reduces the risk of disrupting the production microbiome, a common side effect of broad-spectrum antibiotics. - To combat the potential for bacteria to develop resistance, a common strategy is the use of "phage cocktails," which are mixtures of multiple phage types that can target different receptors on the bacterial cell surface. - Several companies are commercializing this technology, including Locus Biosciences, which is developing CRISPR-enhanced phages for more precise targeting, and Intralytix, which has a history of developing phage products for food safety applications. - The regulatory pathway is becoming clearer; in the U.S., phages are regulated as biological products by the FDA, while in Europe, a new general chapter in the European Pharmacopoeia for phage therapy products came into force in January 2025, establishing harmonized quality standards. - Beyond bioreactors, phage biocontrol is already applied in the food industry to eliminate specific pathogens like *Listeria monocytogenes*, *Salmonella*, and *E. coli* on food products and processing surfaces. - Key technical challenges in manufacturing phage therapeutics at scale include selecting the correct host strain for replication, preventing the phage from entering a dormant (lysogenic) state instead of killing the bacteria, and removing bacterial endotoxins during purification.
