Difference between revisions of "Part:BBa K2610034"

(Usage and Biology)
 
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<partinfo>BBa_K2610034 short</partinfo>
 
<partinfo>BBa_K2610034 short</partinfo>
  
This composite part features twice the regulatory part promoter SoxS (BBa_) and the fluorescent protein GFP (BBa_E0040). It can be used to visualize upregulation of SoxS as a result of superoxide stress.  
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This composite part features twice the regulatory part promoter pSoxS ([https://parts.igem.org/Part:BBa_K2610030 BBa_K2610030]) and the fluorescent protein GFP ([https://parts.igem.org/Part:BBa_E0040 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 a superactivator of downstream stress genes.
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Regulatory protein SoxS is involved in the oxidative stress signaling pathway in <i> Escherichia coli </i>. 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===
 
===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.  
 
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.
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As can be observed in Figure 1 the pSoxS-GFP-pSoxS-GFP construct leads to an increased mean fluorescence intensity compared to pSoxS-GFP. This activation was demonstrated through treatment of the transformed <i> E.coli </i> cells with nalidixic acid. We successfully thus amplified the pSoxS-GFP stress reporter strain by increasing the number of promoters and GFP genes in the plasmid. This enables detection of even lower concentrations of stressful substances, allows signals to be detected by less sensitive detection devices and facilitates faster signal detection.
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In addition, we 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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[[File:T--Leiden--amplificA.png|300px]] [[File:T--Leiden--amplificB.jpeg|300px]]<br><br>
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<span style="font-size:1em"><b>Figure 1.</b> Mean fluorescence intensity (MFI) as a result of treatment with nalidixic acid for pSoxS-GFP compared to pSoxS-GFP-pSoxS-GFP. It can also be seen that there is a dose response curve to nalidixic acid. The decrease in GFP expression at higher concentrations of nalidixic acid can be attributed to lethality of the compound. </span>
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[[File:T--Leiden--amplification.png|750px]] <br>
 
<span style="font-size:1em"><b>Figure 1.</b> Median fluorescence intensity (MFI) as a result of treatment with nalidixic acid for three promoter-GFP constructs. </span>
 
  
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.
 
  
[[File:T--Leiden--amplification2.png|750px]] <br>
 
<span style="font-size:1em"><b>Figure 2.</b>  Dose-response curve as a result of treatment with nalidixic acid. </span>
 
  
 
<!-- Add more about the biology of this part here
 
<!-- Add more about the biology of this part here

Latest revision as of 02:26, 18 October 2018


pSoxS-GFP-pSoxS-GFP

This composite part features twice the regulatory part promoter pSoxS (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 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. This activation was demonstrated through treatment of the transformed E.coli cells with nalidixic acid. We successfully thus amplified the pSoxS-GFP stress reporter strain by increasing the number of promoters and GFP genes in the plasmid. This enables detection of even lower concentrations of stressful substances, allows signals to be detected by less sensitive detection devices and facilitates faster signal detection.

In addition, we 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.

T--Leiden--amplificA.png T--Leiden--amplificB.jpeg

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



Sequence and Features


Assembly Compatibility:
  • 10
    COMPATIBLE WITH RFC[10]
  • 12
    COMPATIBLE WITH RFC[12]
  • 21
    COMPATIBLE WITH RFC[21]
  • 23
    COMPATIBLE WITH RFC[23]
  • 25
    COMPATIBLE WITH RFC[25]
  • 1000
    INCOMPATIBLE WITH RFC[1000]
    Illegal BsaI.rc site found at 947
    Illegal BsaI.rc site found at 1978