M2 Genetic Circuit

Video

Genetic circuit

Elaboration

Genes RcsB, YgiV and Rfal control the production of colanic acid. RcsB is concerned with generating colanic acid, YgiV increases the yield and Rfal attaches the colanic acid produced, to the outer membrane of E. coli.

Genes OtsA and OtsB are involved in the production of trehalose.

Encapsulation is induced automatically when the concentration of glucose decreases below threshold. Initially, glucose concentration is high and this represses the CRP promoter. No transcription occurs and encapsulation does not occur. As E. coli grows, it consumes glucose, resulting in a decrease in glucose concentration until the threshold is reached. At this point, glucose will no longer be able to repress the CRP promoter. Colanic acid and trehalose would be produced.