Part:BBa_K3989012

EsaR regulator

EsaR is a regulator protein which regulates the promoter of a bacterial Quorum Sensing system. By interacting with the Quorum Sensing molecules(a class of molecules called AHL.In our project, the molecule is called 3OC6HSL since it shows a higher sensitivity), it can either act as a repressor or an activator depending on the location of the promoter it binds.

How it works

In the P_esa promoter controlled Quorum Sensing system, EsaR acts as a regulator that can bind to a specific site of the promoter P_esa. Depending on the different types of the P_esa(P_esaR and P_esaS), EsaR can be either a repressor(for P_esaR) or an activator(for P_esaR). The detailed mechanism is shown below:

Figure 1. EsaR acts as either an activator or a repressor.

From the figure we can see that, the EsaR protein binds to a specific site called the esa box. This binding site has a different location on P_esaR and P_esaS and the EsaR binds to it when there is no AHL molecules exist. However, when interacting with AHL, the EsaR will perform an allocation change. Subsequently, it will dislocate from the binding site and will either recruit or interfere the RNA polymerase for the transcription.

Characterisation

Previous studies