M3 Genetic Circuit

Genetic Circuit

Elaboration

This is the genetic circuit for Module 3. Thermally induced genome deletion is kicked off when the temperature is increased to 42°C.

This construct has two main components. The first component controls the production of restriction enzymes DpnII and TaqI. The second component ensures the production of Dam methylase, which protects the DNA.

Protein production and encapsulation occurs at 28°C. In addition, protein cI is produced constitutively at 28°C. It represses the lambda cI promoter, inhibiting restriction enzyme production. The production of Dam methylase protects the E. coli DNA, preventing basal levels of restriction enzyme from causing premature cell death.

When sufficient protein is being produced and encapsulation is complete, the temperature will be increased to 42°C. This results in the de-repression of the pLambda promoter and restriction enzymes DpnII and TaqI will be produced. Dam methylase will be insufficient to protect the E. coli DNA from being cut and genome deletion would occur. This causes cell death and destruction of possible pathogenicity from E. coli.