Antibiotic-free Fermentation

Apr 21, 2022

We are excited to announce our new technology for antibiotic-free bacterial fermentation.

This new technology offers a superior alternative to antibiotic-based plasmid maintenance. The use of antibiotic resistance for plasmid maintenance is a standard practice in biotechnology; however, it has drawbacks in terms of costs, regulatory compliance, and productivity.
Antibiotics are expensive for industrial-scale production, and their use in biomanufacturing necessitates additional costly analytical and purification steps to ensure the product is free from residual antibiotics. Antibiotic contaminants are a growing concern from industrial, medical, and regulatory perspectives. As a result, the current trend in biomanufacturing is to forgo use of antibiotics in the fermentation culture, despite the resulting loss in productivity due to enrichment of plasmid-free bacteria.

Furthermore, the presence of an antibiotic resistance gene in the vector backbone is considered undesirable by health authorities due to the associated risk of horizontal gene flow. From a productivity standpoint, the expression of an antibiotic resistance marker poses a metabolic burden on the production strain, depleting resources that could otherwise be channeled into biomanufacturing.

We have developed a plasmid maintenance system that is completely independent of antibiotics: there are no antibiotics needed in the culture and no antibiotic resistance genes in the cells.

This patented technology is based on replacement of an essential endogenous gene of the fermentation strain with an inducible genomic copy of that gene, paired with constitutive expression of the essential gene on a plasmid. In the absence of the inducer, the plasmid is essential for growth, ensuring optimal plasmid maintenance. Importantly, expression of the genomic copy of the essential gene can be induced so that the bacterial strain can be propagated without a plasmid, allowing the strain to be easily transformed with a new plasmid without cumbersome strain modifications or helper plasmids.

Interested? Please contact us for more information.


We have filed two patents for this technology:
EP21174990: Microorganism strain and method for antibiotic-free plasmid-based fermentation, 20 May 2021
EP22160310: Microorganism strain for antibiotic-free plasmid-based fermentation and method for generation thereof, 04 March 2022

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