Difference between revisions of "Team:UofC Calgary/Composite Part"

The backbone of the U of Calgary project are the composite parts. Our composite parts are an amalgamation of different registry parts which act together to provide a novel function. The composite parts designed for this project are based around the modified Bowman-Birk Protease Inhibitor (mBBI) and the competency-inducing ComK part that was submitted to the registry by the 2014 UofC_Calgary team.

A variety of different parts were used across all of the mBBI composite constructs. We used Pveg, a constitutive E. coli and B. subtilis promoter, and double terminators to book-end internal genes upon chromosomal integration. To improve secretion and transdermal delivery of mBBI from B. subtilis, we added a secretion (sec) tag as well as a transdermal (TD1) tag. The secretion tag is a localization tag for the Sec pathway in B. subtilis (Ruan et al., 2013). TD1 is a part previously developed by the USTC_China 2013 iGEM team, and it is designed to allow for the trafficking of peptides across the skin.

The second major composite part was the ComK construct. ComK is a transcription factor and master regulator for competency in B. subtilis. We modified the original ComK sequence, which was first submitted by the 2014 UofC_Calgary team, to remove unwanted restriction sites from within the comK gene itself. The comK gene and xylose-inducible promoter were then flanked with sequences homologous to the amyE locus in B. subtilis, a non-essential gene responsible for the degradation of starch. These flanking sequences were added to allow for the integration of a controllable ComK into the B. subtilis genome. The integration of a xylose-inducible ComK allows for the transformation of B. subtilis to be more time-efficient and less resource-intensive.

Our last construct does not fall into either of the two previous categories. The construct is an integration cassette, which is a mix of both the mBBI and Comk constructs. Our cassette contains thrC integration sequences which flank the sec and TD1 tag. However, the mBBI sequence is replaced with the restriction sites for BamHI and XmaI restriction enzymes. Addition of the restriction sites allows for directional cloning of any desired insert, allowing B. subtilis to be used as a platform for future biotherapeutics, creating a mini-pharmacy.