Part:BBa_K1960004
Low-level expression of LuxR and the lux pR promoter
BBa_A340620 with constant promoter. This part is based on the quorum sensing system of Gram-negative bacterium.
Usage and Biology
Research shows that quorum sensing plays an important role in the communication between bacteria. Quorum-sensing bacteria can express and release some small chemical signal molecules called autoinducers. The concentration of the autoinducers increases as a function of cell density. The bacteria can detect a minimal threshold stimulatory concentration of autoinducers, then it will lead to the relevant gene expression. In this case, we designed our sensor based on it.
One quorum sensing system in Gram-negative bacteria is LuxI-LuxR type. LuxI is the autoinducer synthase to produce the acyl-homoserine lactone (AHL) autoinducer, and LuxR is a protein which can bind AHL autoinducer and then activate transcription .In our sensor, the right hand lux promoter (pLuxR) can be activated by LuxR-AHL component
Figure. The diagram of the mechanism that the AHL is sensed by the Lux system sensor part.
Our sensor consists of a promoter BBa_J23100 and LuxR gene and Lux pR BBa_A340620. The BBa_J23100 is a strong promoter that is on in strains without any inducer, so LuxR gene can express constantly. The concentration of the AHL up to the threshold, the autoinducer AHL binds LuxR. Then the promoter lux pR will be activated, the responder starts to express.
Sequence and Features
- 10COMPATIBLE WITH RFC[10]
- 12INCOMPATIBLE WITH RFC[12]Illegal NheI site found at 7
Illegal NheI site found at 30 - 21COMPATIBLE WITH RFC[21]
- 23COMPATIBLE WITH RFC[23]
- 25COMPATIBLE WITH RFC[25]
- 1000INCOMPATIBLE WITH RFC[1000]Illegal BsaI.rc site found at 985
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