Composite

Part:BBa_K2176001:Design

Designed by: Miranda Halle   Group: iGEM16_UChicago   (2016-07-19)


Cassette for the constitutive production of GAL4-KaiCp and LexA-SasA, linked by a self-cleaving P2A


Assembly Compatibility:
  • 10
    INCOMPATIBLE WITH RFC[10]
    Illegal prefix found in sequence at 6
    Illegal SpeI site found at 4479
    Illegal PstI site found at 4465
  • 12
    INCOMPATIBLE WITH RFC[12]
    Illegal EcoRI site found at 6
    Illegal SpeI site found at 4479
    Illegal PstI site found at 4465
    Illegal NotI site found at 12
    Illegal NotI site found at 4470
  • 21
    INCOMPATIBLE WITH RFC[21]
    Illegal EcoRI site found at 6
  • 23
    INCOMPATIBLE WITH RFC[23]
    Illegal prefix found in sequence at 6
    Illegal SpeI site found at 4479
    Illegal PstI site found at 4465
  • 25
    INCOMPATIBLE WITH RFC[25]
    Illegal prefix found in sequence at 6
    Illegal XbaI site found at 21
    Illegal SpeI site found at 4479
    Illegal PstI site found at 4465
  • 1000
    INCOMPATIBLE WITH RFC[1000]
    Illegal BsaI.rc site found at 206
    Illegal BsaI.rc site found at 3479


Design Notes

We chose to express both fusion proteins in one cassette, joined by a self-cleaving linker, in order to obtain equal stoichiometric amounts in the cell.

In order to join the promoter and terminator to the protein coding sequence, we used two restriction enzymes, BamHI and BglII, which produce the same sticky ends when cut but have different recognition sites due to differences in the base pairs flanking the sticky ends. The promoter was cut with BamHI, while the side of the protein coding sequence it was to be joined to was cut with BglII. These two were then able to ligate together, which produced a novel 6bp sequence that is half-BamHI site, half-BglII site, and as a result is a recognizable cut site to neither. The same procedure was used to join the protein coding sequence and the terminator.


Source

The promoter and terminator in this cassette were amplified from the yeast genome, using primers that added extra overhangs with novel restriction enzyme cut sites on either end: the BioBrick prefix (for the promoter) or suffix (for the terminator) on one side, and an overhang with a cut site for ligating the part to the protein coding sequence on the other side. The protein coding domain was synthesized in G-blocks and constructed via Gibson assembly. None of these components came from their own BioBricks, which is why we've entered the composite as a single "Basic" part.

References