Types | DnaRegion
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Roles | Signalling
engineered_region
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Sequences | BBa_K658014_sequence (Version 1)
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Description
Quorum sensing is used by a number of gram-negative bacterial genera to regulate expression of specific sets of genes in a cell density-dependent fashion. We constructed the part which expresses LuxI and LuxR upon induction by isopropyl-b-D-thiogalactopyranoside (IPTG). There are two regulatory genes involved in quorum sensing, the I and R genes. The I gene directs the synthesis of an acyl-homoserine lactone (AHL) signal molecule termed the autoinducer. The R gene codes for a transcription factor that is responsive to the N-acyl HSL signal. Cells are permeable to this signal, and thus high cell densities are required to achieve a critical concentration of the autoinducer required to bind the luxR product, which will be combined with lux pR and then the expression downstream genes could be started. Site-directed mutagenesis has been used to modify the promoter lux pR in this signalling device. We have generated three point mutants by site-directed mutagenesis, designated lux pR-3 (BBa_K658006), lux pR-5(BBa_K658007) and lux pR-3/5(BBa_K658008). This signalling device is usually used to connected with some protein coding sequence,The promoter lux pR-5 (BBa_K658007) at the end of this sequence regulates the expression of downstream genes.
Notes
This signalling device is based on the quorum sensing system in V. Fischri. Different from an autoinduction system, this signalling circuit starts only at the presence of inducer IPTG which does not exist in the natural QS system.
Source
F1610
K658000