Team:Tec-Monterrey/projectmodeling

The first DNA construction our team used, was called “Construct ompA+GFP” this assembly was made in order to obtain data from our araC-P_BAD promoter. Our team worked with parts from British Columbia 09 team. Part BBa_K206000, P_BAD, is an Escherichia 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 P_BAD 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 L-arabinose (our inductor).

Schlief, R. (2000). Regulation of the L-arabinose operon of Escherichia coli. Trends in Genetics. 16(12):559-565.