The first DNA construction our team used, was called “Construct ompA+GFP” this assembly was made in order to obtain data from our araC-PBAD promoter. Our team worked with parts from British Columbia 09 team. Part BBa_K206000, PBAD, is an E.coli promoter that is induced by L-arabinose. In the absence of arabinose, the repressor protein AraC, BBa_I13458 , binds to the AraI1 operator site of PBAD and the upstream operator site AraO2, blocking transcription [1]. In the presence of arabinose, AraC binds to it and changes its conformation such that it interacts with the AraI1 and AraI2 operator sites, permitting transcription.
BBa_K206000 is a variant pBAD promoter with a modified AraI1 site that has been shown both to be responsive to lower concentrations of arabinose and to exhibit a higher maximum expression than the wild type (BBa_I13453), as measured by coupling to a fluorescent reporter by iGEM09 British Columbia Team.
We aslo used as a RBS the Kozak sequence used normally on most constructs, part BBa_B0034, followed by a Green Fluorecent Protein (BBa_b0040), supposed to act as a reporter in order to meassure effectivness of the arabinose promoter. This construct was meassured in E. coli strain BW27783, which is unable to metabolize arabinose, (our inductor).
Schlief, R. (2000). Regulation of the L-arabinose operon of
Escherichia coli. Trends in Genetics. 16(12):559-565.