Difference between revisions of "Part:BBa K584001"

Revision as of 07:03, 21 September 2011

Constitutive promoter + GFP generator

This part was designed to test the functionality of the constitutive promotor region.

Characterization

We fused the constitutive promoter to a GFP reporter, and assayed the promoter’s activity after addition of different amounts of arabinose and IPTG. As such these results can serve as a control for the results obtained for the arabinose-inducible BBa_K584000 and IPTG-inducible BBa_K584002 bricks. We tested the activity both in a TOP10F’ (figure 1 & 3) as well as a MG1655 (figure 2 & 4) E.coli strain background. For more information on E.coli strain descriptions, we recommend the following website: [http://openwetware.org/wiki/E._coli_genotypes E.Coli_Genotypes].

Figure1

Figure2

Apart from a small growth defect and somewhat lower fluorescence at the 8 hour time point after the addition of 2% arabinose, the activity of the constitutive promoter in TOP10F’ cells is unaffected by arabinose addition, as seen in Figure1. For the MG1655 cells (Figure 2), however, we see clear effects of adding arabinose at concentrations of 0.2% or 2%, with promoter activities significantly lower than the control condition. This points to interference of high inducer levels with the activity of the promoter and the importance of metabolism of the inducer, as arabinose can be metabolized by MG1655 cells, but not by TOP10F’ cells.

Figure3

Figure3

For both TOP10F’ and MG1655 cells, the activity of the constitutive promoter is unaffected by the addition of IPTG (Figures 3 and 4).

Figure4

Sequence and Features