Team:Northwestern/Improve
IMPROVE A PART
EXISTING PART
The part we are improving is BBa_K079050, a DNA damage sensor originally used by the 2008 Bologna Team. It contains a reporter gene, GFP, downstream of a constitutive promoter and a LexA operator. The LexA operator used in this part is the LexA 2 operator in the iGEM LexA operator library. The Bologna team was unable to induce significant fluorescence by just UV induction, so the goal for our improvement was to modify the design of their part in order to reach obtain Fluorescence induction via UV exposure. For more information about this existing part, here.
Part BBa_K079050
OUR IMPROVEMENT
We are switching the LexA 2 operator with the LexA 1 operator from the iGEM library, part BBa_K079039.
Improved Part
RESULTS
This experiment was run in parallel with our Part Validation assay (See Part validation on our experiments page for our Methods). Unfortunately, no fluorescence was observed from our newly designed part (Figure 1). However, the readout for the original part was successful, as seen below in Figure 1, resulting in a novel characterization of the part. This discrepancy between our results and the previously reported data could be due to several factors such as different UV exposure methods used and different cell strains used. Although there is no difference in initial induction, there is a significant difference between the dilution of GFP as the cells continue to grow between each exposure time for the LexA2 cells.
Figure 1. Fluorescence/OD600 for parts BBa_K3269004 (LexA1) and BBa_K079050 (LexA2). The time value next to each title is the exposure time for each sample
Figure 1. Fluorescence/OD600 for parts BBa_K3269004 (LexA1) and BBa_K079050 (LexA2). The time value next to each title is the exposure time for each sample