Part:BBa_M50499:Design
Catabolite Activator Protein (CAP) Repressed Promoter
We placed the constitutive promoter (BBa_S05450, iGEM) immediately upstream from a catabolite activator protein (CAP) binding site (BBa_M36547, iGEM). When CAP binds to the binding site, expression will be repressed.
- 10INCOMPATIBLE WITH RFC[10]Illegal XbaI site found at 1059
Illegal PstI site found at 688
Illegal PstI site found at 849 - 12INCOMPATIBLE WITH RFC[12]Illegal NheI site found at 144
Illegal NheI site found at 167
Illegal PstI site found at 688
Illegal PstI site found at 849 - 21COMPATIBLE WITH RFC[21]
- 23INCOMPATIBLE WITH RFC[23]Illegal XbaI site found at 1059
Illegal PstI site found at 688
Illegal PstI site found at 849 - 25INCOMPATIBLE WITH RFC[25]Illegal XbaI site found at 1059
Illegal PstI site found at 688
Illegal PstI site found at 849 - 1000COMPATIBLE WITH RFC[1000]
This construct is an adaption of the natural lac operon, which is positively regulated by CAP, since the CAP binding site is naturally upstream of the RNA polymerase binding site. In this construct, we put the CAP binding site downstream in order to repress transcription due to steric hindrance when CAP binds.
Design Notes
This construct is an adaption of the natural lac operon, which is positively regulated by CAP, since the CAP binding site is naturally upstream of the RNA polymerase binding site. In this construct, we put the CAP binding site downstream in order to repress transcription due to steric hindrance when CAP binds.
Since CAP binding is inversely correlated to glucose concentrations (and positively correlated with cyclic AMP (cAMP) levels), this promoter exhibits glucose-inducibility and cAMP-repressibility. We employed this construct as a potential DNA-based glucose biosensor in E coli.
Source
We used only pre-existing iGEM parts: the constitutive promoter (IGEM part: BBa_S05450) and the CAP binding site (IGEM part: BBa_M36547). The CAP binding site was actually from a previous BioE44 project! We confirmed the CAP sequence from a paper as well (www.ncbi.nlm.nih.gov/pmc/articles/PMC338411).
References
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