Regulatory

Part:BBa_K1214007

Designed by: Alec Spinhirne   Group: iGEM13_UT_Dallas   (2013-09-16)

pFru

Fructose operon promoter. Regulated by fructose operon repressor Cra (BBa_K1214008). Also used in parts BBa_K1214011 and BBa_K1214013.

Usage and Biology

Sequence and Features


Assembly Compatibility:
  • 10
    COMPATIBLE WITH RFC[10]
  • 12
    COMPATIBLE WITH RFC[12]
  • 21
    COMPATIBLE WITH RFC[21]
  • 23
    COMPATIBLE WITH RFC[23]
  • 25
    COMPATIBLE WITH RFC[25]
  • 1000
    COMPATIBLE WITH RFC[1000]


Biology

The FruR gene encodes a protein which normally binds to and represses pFru promoter. When fructose is present in the system, it binds to the FruR protein and prevents it from repressing the operon promoter.
http://i826.photobucket.com/albums/zz188/lana_khazma/fancy%20stuff/fruRstuff_zpsaf5e8f5b.png

Testing

Promoter Strength


Promotion was tested against pScr (BBa_K1214006) and the medium constitutive promoter (BBa_K823014) using Flow cytometry. All three promoters were ligated in front of RBS-GFP to constitutively express GFP. The cells were inoculated for 18 hours at 37 C in 3 mL of chloramphenicol broth and then examined under fluorescent microscopy.

Comparison of microscope images for these promoters:
FDcpGFP.jpg
FDpFruGFP.jpg
FDpScrGFP.jpg

The expression of GFP under control of pFru is visibly greater than that of either other promoter.

Flow cytometry was then completed to determine Mean GFP. FlowPromoters.png
This shows that the pFru promoter strength is 249% greater than the medium constitutive promoter in this reporter system.




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Categories
Parameters
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