Difference between revisions of "Part:BBa K2610035"

Revision as of 02:21, 18 October 2018

pSoxS-GFP-GFP-pSoxS-GFP-GFP

This composite part features twice the regulatory part promoter SoxS (BBa_K2610030) and two times 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 oxidative stress signaling pathway in Escherichia coli . Intracellular superoxide-generating compounds cause the SoxR to activate transcription of SoxS, which then triggers a set of defense and repair genes that form the oxidative response system.

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 pSoxS-GFP-pSoxS-GFP construct leads to an increased mean fluorescence intensity compared to pSoxS-GFP (BBa_K2610031), but not compared to pSoXS-GFP-pSoxS-GFP (BBa_K2610034).

We also assessed the dose-dependency of this reporter. We found that an increase in nalidixic acid concentration of nalidixic acid leads to an increasing mean fluorescence intensity (MFI). A decrease in detected GFP expression at higher concentrations can be attributed to the lethality of the stressor.

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Figure 1. Median fluorescence intensity (MFI) as a result of treatment with nalidixic acid for pSoxS-GFP-GFP-pSoxS-GFP-GFP compared to pSoxS-GFP-pSoxS-GFP and pSoxS-GFP . It can also be seen that there is a dose response curve to nalidixic acid. The decrease in detected GFP expression at higher concentrations can be attributed to lethality of the stressor.

Sequence and Features