Designed by: M. Hesselman   Group: iGEM11_Wageningen_UR   (2011-09-14)

Lux pL controlled LuxR with lux pR autoinducing LuxI(lva tag)- AHL.

This device has two protein generators:

lux pl-RBS-C0062-B0015 produces LuxR. LuxR forms a complex with the quorum sensing molecule AHL and this complex subsequently increases the transcriptional rate of the lux pR promoter while also decreasing the transcriptional rate of the lux pL promoter.

The quorum sensing molecule AHL is produced by LuxI which is under the control of the lux pR promoter. In combination with LuxR, AHL thus increases the production of AHL, a positive feedback loop.

Experimental data

For determining the experimental data this part was combined with K546002, together K546005. Fluorescence of a culture with OD600 of 0.6 was monitored over time in a plate reader:

The GFP expression rapidly increases, indicating functionality of this part. The formed AHL from LuxI forms a complex with LuxR and induces pR, that controls GFP expression. As a result, a positive feedback loop is initiated.

Safety Aspects

There's a small note regarding the biosafety of this BioBrick composite part. Upon release into the environment (this includes infection of a laboratory worker) this BioBrick composite part might alter the pathogenicity of pathogens that rely on quorum sensing to infect hosts. Pathogenic species that might be involved can be found on the following external biological safety page.

Sequence and Features

[edit]

Categories

Twins More...

control	(1) R0063 & (2) R0062
device_type	feedback
direction	Forward
latency	Seconds
protein	(1) LuxR & (2) luxI-LVA
signalling_molecule	3OC6HSL (AHL)
switch_point	(1) 2nM