Related Experiment Videos
Streptavidin-based containment systems for genetically engineered microorganisms.
1Department of Chemical Engineering and Biotechnology Center, Tufts University, Medford, MA 02155, USA. dkaplan1@tufts.edu
Biomolecular Engineering
|May 5, 2000
Summary
Genetically modified bacteria for environmental cleanup can be controlled using streptavidin-based suicide systems. This method effectively eliminates 99.9% of the bacterial culture when the hydrocarbon substrate is absent.
Area of Science:
- Environmental microbiology
- Biotechnology
- Genetic engineering
Background:
- Genetically modified microorganisms (GMMs) offer potential for environmental remediation but raise safety concerns.
- Conditional lethal systems and regulated gene expression are key to containing GMMs and preventing horizontal gene transfer.
Purpose of the Study:
- To develop and evaluate streptavidin-based suicide systems for controlling GMMs.
- To assess the efficacy of these systems in Pseudomonas putida engineered for aromatic hydrocarbon metabolism.
Main Methods:
- Constructed and tested a conditional lethal system utilizing a truncated streptavidin gene.
- Implemented tight regulation of streptavidin gene expression.
- Induced bacterial elimination by removing the hydrocarbon substrate (3-methyl benzoate).
Main Results:
- Tight regulation of streptavidin expression was crucial to prevent premature toxicity.
- Induction by substrate absence led to 99.9% bacterial culture elimination within eight hours.
- Achieved low mutant escape rates of 10(-7) per cell per generation.
Conclusions:
- Streptavidin-based suicide systems provide effective containment for GMMs used in environmental remediation.
- Regulated gene expression is vital for the safe deployment of engineered microorganisms.
- These systems significantly reduce risks associated with horizontal gene transfer.