Summary The idea Promoter calibrator Biological comparator Electronic comparator Biological controller Lab Work Silico Work Results Adversities

During the brainstroming, an idea came up: mimetize an electronic comparator on a biologcal device. It works with repressors, so it may sound familiar to most of us.


Two inputs enter the system, a genetic circuit compares both signals and amplifies the higher one.


So easy, I would be quite surprised if we don't find any drawback.

Two different promoters that act as sensors of different inputs and two repressors that inhibit each other.

  1. We have two promoters that 'sense' something: psensorA and psensorB
  2. We have two promoters repressed: pLacI and ptet
  3. We also have two CDS of the repressors: lacI and tetR
  4. And, finally, we have the outputs: CFP and YFP

The system would be:


So, if we have equal amount of whatever A and B, there will be equal amounts of both repressors and, so, equal amounts of CFP and YFP. If some input A is sensibly higher than the B, we will have more tetR that will inhibit ptet and we will have less YFP

What for:

We would have a device that would clear the noise of a system, (only reducing it to zero at infinite time). It can be used in other projects, as it implies only two genes and 4 promoters...


  • Will a gene driven by two different promoters work well enough?? ETH tried it with some results, why not give it a try?
  • It's a small project, but it can be coupled to some other project...
  • We still have to find some new BioBricks to build, as almost every single construction would be on the iGEM plate

Developed by: Arnau, Pablo and Javi