IGEM:IMPERIAL/2006/project/Oscillator/project browser/Prey Construct/Design
|Super Parts||Molecular Prey-Predator Oscillator|
|Sub Parts||Test Sensing Prey Construct||<bbpart>C0261</bbpart>||<bbpart>I13401</bbpart>|
- The prey part: J37015 @ MIT Parts Registry
- Design must fulfil the specifications for the prey construct.
- Part design will be based on Quorum-sensing/quenching and the availability of BioBricks.
- Research into the registry directed us to use AHL as our prey molecule.
- Design allows for an exponential increase of AHL (to fulfil the Lotka-Volterra model) via a positive feedback loop.
- The prey part can be decoupled into a prey sensing part and a prey producing part.
- Initiation of positive feedback loop depends on leaky expression of the tetR promoter which is a constitutive promoter.
- This leaky expression produces LuxR which can form a dimer with AHL already withing the cell.
- LuxR, AHL and promoter control the expression of LuxI which produces AHL.
- Design allows for assesment of status of positive feedback loop via:
- GFP Production - Linked to LuxI expression
- AHL Production - Can be indirectly assessed according to J37015 protocol.
|AHL||LuxR & pLuxR||To initiate the positive feedback loop, LuxR is produced via leaky expression of the tetR promoter.|
|AHL||LuxI||LuxR, AHL and pLuxR form a complex, activating production of LuxI expression which causes enzymatic generation of AHL|
- We need to consider methods of controlling the positive feedback loop while cells are growing to ensure AHL concentration stays at zero. Possible suggestions are:
- Periodic dilution of culture to allow degradation of LuxI
- Pops blocker