Scaling to 10,000L: Stability Case Study
From shake flask to industrial fermenter without the performance drop.
Sogand Azadeh
Co-Founder & Research Lead
The Linear Scaling Myth
Every bioprocess engineer knows that what works in a 250mL shake flask rarely behaves the same in a 10,000L steel tank. Shear stress, oxygen gradients, and mixing times introduce new selection pressures that accelerate genetic drift. The extended seed trains required to inoculate a large vessel mean that cells have undergone dozens of doublings before the production phase even begins.
Trial Parameters
| Parameter | Control (Standard BL21) | Catcheater Strain |
|---|---|---|
| Vessel Volume | 500L | 500L |
| Induction Time | OD 0.8 | OD 0.8 |
| Antibiotic | Ampicillin (100ug/mL) | None |
| Duration | 72 Hours | 72 Hours |
Outcomes
1. Plasmid Retention: The Control group dropped to 45% plasmid retention by hour 48. The Catcheater group maintained 99.8% retention through hour 72.
2. Titer: Final protein titer for Catcheater was 3.8 g/L compared to 1.9 g/L for the control.
3. Cost: Eliminating the antibiotic reduced media costs by 12% at this scale, with projected savings of over €50k/run at the 10,000L scale.
Regulatory & Downstream Benefits
Beyond yield, the removal of antibiotics simplifies the entire downstream processing (DSP) workflow.
There is no need to validate the removal of trace antibiotics from the final product, a key requirement for FDA approval of injectables.
Furthermore, the Catcheater system significantly reduces the bioburden of "dead" biomass. While cheaters are lysed, they convert their biomass back into soluble amino acids and nucleotides, which can be scavenged by the productive survivors.
This effectively turns the cheater into feedstock for your product.