DNA

Part:BBa_K3805209

Designed by: Lijuan Wang   Group: iGEM21_BNU-China   (2021-09-30)


Bi-stable Switch

(Toggle Switch)

This part is a Bi-stable switch(toggle switch).It is composed of trc promoter(BBa_K3805208))[1], P2 promoter(BBa_I746104))[2], lacI- LVA (BBa_C0012))[3]and ompT-mcherry(BBa_K3805886))[4].


Usage and Biology

At the presence of autoinducing peptides(AIPs), P2 promoter will be activated by phosphorylated AgrA (BBa_K38055))[5]and initiate the expression of downstrem lacI-LVA and ompT. LacI-LVA inhibits trc promoter.As the concentration of AIP decreases, the downstream transcription of P2 promoter will be down-regulated and the inhibition of lacI-LVA on the trc promoter will thus be lifted.The trc promoter then initiates the its downstream expression.


Figure 1 Images under fluorescence microscope.(A)Before putting into AIPs, red fluorescence was observed.(B).After putting into AIP, red fluorescence disappeared,green fluorescence was observed. (fluorescence microscope 10x100)



Sequence and Features


Assembly Compatibility:
  • 10
    COMPATIBLE WITH RFC[10]
  • 12
    COMPATIBLE WITH RFC[12]
  • 21
    INCOMPATIBLE WITH RFC[21]
    Illegal BglII site found at 1287
  • 23
    COMPATIBLE WITH RFC[23]
  • 25
    COMPATIBLE WITH RFC[25]
  • 1000
    COMPATIBLE WITH RFC[1000]


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Parameters
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