Difference between revisions of "Part:BBa K2610034"

Revision as of 09:08, 11 October 2018

pSoxS-GFP-pSoxS-GFP

This composite part features twice the regulatory part promoter SoxS (BBa_K2610030) and the fluorescent protein GFP (BBa_E0040). It can be used to visualize upregulation of SoxS as a result of superoxide stress.

Regulatory protein SoxS is involved in the superoxide pathway in Escherichia coli. It acts as a superactivator of downstream stress genes.

Usage and Biology

We, iGEM Leiden 2018, have designed this composite part as part of our project Fifty Shades of Stress. This reporter part allowed us to detect stress-induced changes in SoxS transcription. We have created this part in order to amplify the fluorescent signal measured after pSoxS-GFP activation.

As can be observed in Figure 1 the double promoter and GFP construct leads to an increased median fluorescence intensity compared to pSoxS-GFP. This activation was demonstrated through treatment of the transformed E.coli cells with nalidixic acid.

Figure 1. Median fluorescence intensity (MFI) as a result of treatment with nalidixic acid for three promoter-GFP constructs.

Moreover, we have demonstrated that our part is responsive to nalidixic acid in a dose-response manner (Figure 2). Concentrations higher than 1 ug/mL lead to death of the bacterial cells. Just before cell death occurs the fluorescence peaks.

Figure 2. Dose-response curve as a result of treatment with nalidixic acid.

Sequence and Features