IGEM:IMPERIAL/2006/project/Oscillator/project browser/Prey Construct/Design

Super Parts	Molecular Prey-Predator Oscillator
Actual Part
Sub Parts	Test Sensing Prey Construct	<bbpart>C0261</bbpart>	<bbpart>I13401</bbpart>

• Specifications
• Design
• Modelling
• Implementation
• Testing/Validation

Registry

• The prey part: J37015 @ MIT Parts Registry

Design Choices

• 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.

INPUTS	biological component	comments
AHL	LuxR & pLuxR	To initiate the positive feedback loop, LuxR is produced via leaky expression of the tetR promoter.
OUTPUTS	biological component	comments
AHL	LuxI	LuxR, AHL and pLuxR form a complex, activating production of LuxI expression which causes enzymatic generation of AHL