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Projects

Design: Wet Lab

Design: Printer

Design: Software

Testing

Construction: The Wetlab

Protocols

Final Result of E.co Lisa

Welcome to our Teams wetalab section. Our wetlab entry consists of several different components, which are described in this section. Just click on the compenent you want to learn more about

Logic Circut Our logic circut allows for very high control over expression of a desired gene

Agarase The protein that degrades agar

BioMarkers Ever wanted to draw on bacteria?

Light Sensor The system that allows are bacteria to see

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Logic Circut

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The sucess of our project is dependent on us having very percise control over the expression of our reporter gene. In order to draw a legible picture our system needs to be able to induce very high expression of agarase under the desired conditions and then almost completely stop agarase expression when the activating conditions are removed. This is because an over expression of agarase might just degarde the entire plate leaving nothing visible as a picture. Initially one of our team members, Dave Curran, designed a very slick and complex system to regulate expression. However as we were running out of time we were forced to rely on a more simplified version. The simplified version works as follows.

In the absence of 660nm light and AHL, both promoters in the circuit are repressed. If the bacteria were then to be exposed to light, the protein LuxR would be produced, but would not activate the promoter lux pR. When AHL is added to the cells that are still in the dark, the lux pR promoter would still not be activated, as the protein LuxR would not be present. But if AHL is added to the cells, and they are then exposed to light, both AHL and LuxR will be present, and so the lux pR promoter will be activated. When this occurs the reporter gene is expressed, and more LuxR is produced so that the system will remain on even when the light is then taken away.

The complicated system functions in much the same way, except it contains one additional level of security, to prevent accidental activation of the system. There is an RNA lock covering the ribosome binding site in front of the second luxR in the plasmid. This way, even if the lux pR promoter is a touch leaky, no LuxR will be produced to fully activate the system.

The application below shows the schematics of both the complex and simple systems. Hovering over a part with the mouse will highlight its corresponding description in the table. Clicking on a part in the diagram will open the registry's page that desribes the part.