Types | DnaRegion
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Roles | Composite
engineered_region
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Sequences | BBa_K1840008_sequence (Version 1)
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Description
This device acts as a detector for glucose (and certain derivatives of it). The double transcription terminator ensures, that only the gene downstream of the gad promotor is influenced by it. The promotor (BBa_K1840003) is contained in the genome of Pseudomonas putida and is situated in front of the enzyme gad (gluconate oxidase). The repressor PtxS can bind the gad promotor sequence and thus prevent the transcription of the gad gene. In case the glucose derivative 2-ketogluconate is present, it binds the promotor and leads to a subsequent conformational change. Hence, the repressor can no longer bind and the gene downstream can be transcribed. In our device, the downstream gene is mCherry, codon optimized for Pseudomonas (BBa_K1840004). Therefore, in the presence of glucose, mCherry is expressed. In various experiments, we could see that this device is in deed working.
Notes
Considerations were made regarding the actual start of the promotor. As promotor sequence we assumed all DNA between the gad gene and the previous gene (upstream). Since this gene is encoded on the opposite strand, the terminator was needed.
Source
The double terminator was already registered in the iGEM catalogue. The kgu promotor comes from the genome of Pseudomonas putida. The mCherry is codon optimized for expression in Pseudomonas. The whole device was synthesized by IDT.