The YEG1 Mechanism
Essential Gene Complementation
The yeast strain lacks an essential gene (YEG1). This gene is carried exclusively by the plasmid, making its presence essential for cell survival.
Cell survival therefore depends on plasmid maintenance, creating a powerful self-selecting system that ensures stable expression without requiring antibiotic selection markers.
Advantages
No antibiotic selection
Eliminates the need for antibiotics, reducing costs and regulatory constraints.
Stable expression
No selection pressure required. Enables the use of rich media to increase biomass.
High plasmid copy number
Maintains a high number of copies to achieve high protein production yields.
