Coding

Part:BBa_K4249002:Design

Designed by: Wenxin Wang   Group: iGEM22_HBUT-China   (2022-09-18)


The expression cassette carrying an ADH1 promoter, NcEgt1 coding sequence and an CYC1 terminator


Assembly Compatibility:
  • 10
    INCOMPATIBLE WITH RFC[10]
    Illegal EcoRI site found at 1461
    Illegal EcoRI site found at 2788
    Illegal XbaI site found at 2145
    Illegal XbaI site found at 3375
  • 12
    INCOMPATIBLE WITH RFC[12]
    Illegal EcoRI site found at 1461
    Illegal EcoRI site found at 2788
    Illegal NotI site found at 3362
  • 21
    INCOMPATIBLE WITH RFC[21]
    Illegal EcoRI site found at 1461
    Illegal EcoRI site found at 2788
    Illegal BglII site found at 1323
    Illegal BglII site found at 1809
    Illegal BglII site found at 2142
    Illegal BglII site found at 2811
  • 23
    INCOMPATIBLE WITH RFC[23]
    Illegal EcoRI site found at 1461
    Illegal EcoRI site found at 2788
    Illegal XbaI site found at 2145
    Illegal XbaI site found at 3375
  • 25
    INCOMPATIBLE WITH RFC[25]
    Illegal EcoRI site found at 1461
    Illegal EcoRI site found at 2788
    Illegal XbaI site found at 2145
    Illegal XbaI site found at 3375
  • 1000
    INCOMPATIBLE WITH RFC[1000]
    Illegal BsaI site found at 90


Design Notes

During the experiment, we found that some regions of the promoter sequence templates are rich in GC residues, which tend to fold into complex secondary structures and might not melt during the annealing phase of the PCR cycle. Also, the primers used to amplify GC-rich regions often have a high capacity to form self- and cross-dimers and a strong tendency to fold into stem-loop structures that can impede the progress of the DNA polymerase along the template molecule. Therefore, instead of PCR method, we obtained the gene expression cassettes by enzyme digestion.



Source

These two gene were codon-optimized for S. cerevisiae, the genes were then ordered as synthetic gene strings from Sangon Biotech (Shanghai). For the acquisition of the gene expression cassettes, taking Ba_K4249001(pTEF1-CpEgt2-tCYC) as an example, the complete coding sequence was amplified by primer pairs, and the obtained fragment was inserted into the plasmid pTEF2, which was double digested by BamHI and EcoRI. Then, the complete gene expression cassette was gained by enzyme digestion.


References