Team:Johns Hopkins/YT/Future


VitaYeast - Johns Hopkins University, iGEM 2011

Promoter/Terminator Library

We plan to continue working on expanding our promoter and terminator library. This will include and surpass the original 21 parts proposed.

Characterizing the Promoters

We plan to proceed to flow cytometry analysis in the near future in order to give future teams detailed data on the expression levels that can be expected from each. We also plan to transform our other promoters into yeast. We hope to conclude this part of the project before the Americas Regional.


We plan to finish ligating the 5 violacein expression cassettes into the PRS416 Vector with a URA3 selectable marker & transform it into a uracil auxotrophic yeast strain. Our library of Golden Gate assembly compatible yeast promoters and terminators will then include the entire violacein pathway (via BsmBI digestion). In the future, this pathway can be used to test novel neochromosomes & complex DNA structures in yeast by selecting for purple colonies.

We plan to finish the violacein loxPsym integration project. We will transform the RPS2 3'UTR into E. coli, thus completing our library of Golden Gate Assembly-compatible yeast promoters and 3'UTRs. We will then combine our promoter/3'UTR library with the violacein genes and a loxPsym linker in a single ligation reaction, where the promoters, 3'UTRs, and violacein ORFs will randomly combine into expression circles with loxPsym sites. The expression circles will then be transformed into the yeast strain containing synIXR, which will be grown up in the presence of estradiol. Estradiol will induce expression of the Cre-EBD fusion protein, which will catalyze loxP recombination, allowing some yeast cells to take up all five violacein genes and begin synthesizing violacein in various amounts depending on the promoters and 3'UTRs that were attached to the violacein ORFs in the random ligation.