Difference between revisions of "Part:BBa K3771100"

Latest revision as of 18:32, 19 October 2021

SoxR

Description

SoxR is a 17 kDa transcription factor of the MerR family. The normal in vivo level of SoxR protein is maintained at a low level of 50-100 molecules per cell, forming a dimer in solution. It contains a [2Fe–2S] cluster, which is essential for reversible one-electron oxidation and reduction to regulate its activity. Only when the [2Fe–2S] cluster is fully oxidized (Fe³⁺-Fe³⁺), SoxR becomes a powerful transcription activator of soxS promoter (up to 100-fold). Reducing the SoxR [2Fe–2S] cluster by one electron (Fe²⁺-Fe³⁺) can eliminate the ability to stimulate SoxS expression^[1]. In response to superoxide-generating agents, SoxR is oxidized and activated, therefore increasing the synthesis of SoxS, which then activates its target gene expression^[2].

Fig.1. The soxRS regulon. The soxRS regulon includes soxR and soxS genes. The soxR gene is expressed innately in cells and SoxR is activated in response to superoxide-generating agents and nitric oxide (NO). Oxidized SoxR acts as a transcriptional activator of soxS gene; SoxS, afterward, enhances the expression of antioxidant genes. Abbreviation: G6PD, glucose-6-P-dehydrogenase^[1].

Usage and Biology

SoxR protein was used to regulate the expression of taurine-producing enzymes. When the [2Fe–2S] cluster is fully oxidized, SoxR acts as a strong transcription activator of soxS promoter^[1]. The sequence of this basic part is the reverse complement of soxR gene from E. coli.

References

1. Pomposiello PJ, Demple B. Redox-operated genetic switches: the SoxR and OxyR transcription factors. Trends Biotechnol. 2001;19(3):109-114. doi:10.1016/s0167-7799(00)01542-0

2. Koo MS, Lee JH, Rah SY, et al. A reducing system of the superoxide sensor SoxR in Escherichia coli. EMBO J. 2003;22(11):2614-2622. doi:10.1093/emboj/cdg252

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
COMPATIBLE WITH RFC[1000]

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 <partinfo>BBa_K3771100 short</partinfo>
 <br><b style="font-size:1.3rem">Description</b>
 <br>
-<br>SoxR is a 17 kDa transcription factor of the MerR family. The normal in vivo level of SoxR protein is maintained at a low level of 50-100 molecules per cell, forming a dimer in solution. It contains a [2Fe–2S] cluster, which is essential for reversible one-electron oxidation and reduction to regulate its activity. Only when the [2Fe–2S] cluster is fully oxidized (Fe<sup>3+</sup>-Fe<sup>3+</sup>), SoxR becomes a powerful transcription activator of soxS promoter (up to 100-fold). Reducing the SoxR [2Fe–2S] cluster by one electron (Fe<sup>2+</sup>-Fe<sup>3+</sup>) can eliminate the ability to stimulate soxS expression<sup>[1]</sup>. In response to superoxide-generating agents, SoxR is oxidized and activated, therefore increasing the synthesis of SoxS, which then activates its target gene expression<sup>[2]</sup>.
+<br>SoxR is a 17 kDa transcription factor of the MerR family. The normal <i>in vivo</i> level of SoxR protein is maintained at a low level of 50-100 molecules per cell, forming a dimer in solution. It contains a [2Fe–2S] cluster, which is essential for reversible one-electron oxidation and reduction to regulate its activity. Only when the [2Fe–2S] cluster is fully oxidized (Fe<sup>3+</sup>-Fe<sup>3+</sup>), SoxR becomes a powerful transcription activator of <i>soxS</i> promoter (up to 100-fold). Reducing the SoxR [2Fe–2S] cluster by one electron (Fe<sup>2+</sup>-Fe<sup>3+</sup>) can eliminate the ability to stimulate SoxS expression<sup>[1]</sup>. In response to superoxide-generating agents, SoxR is oxidized and activated, therefore increasing the synthesis of SoxS, which then activates its target gene expression<sup>[2]</sup>.
 <br>
 <html><div style="width=100%; display:flex; align-items: center; justify-content: center;">
-<img src="https://static.igem.org/mediawiki/parts/3/37/T--NCKU_Tainan--oxidative_stress%28csad%29.gif" style="width:50%;">
+<img src="https://2021.igem.org/wiki/images/b/b8/T--NCKU_Tainan--soxRS_regulon.png" style="width:50%;">
 </div></html>
 <p align="center">Fig.1. The <i>soxRS</i> regulon. The <i>soxRS</i> regulon includes <i>soxR</i> and <i>soxS</i> genes. The <i>soxR</i> gene is expressed innately in cells and SoxR is activated in response to superoxide-generating agents and nitric oxide (NO). Oxidized SoxR acts as a transcriptional activator of <i>soxS</i> gene; SoxS, afterward, enhances the expression of antioxidant genes. Abbreviation: G6PD, glucose-6-P-dehydrogenase<sup>[1]</sup>.
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 <br>
-<br>SoxR protein was used to regulate the expression of taurine-producing enzymes. When the [2Fe–2S] cluster is fully oxidized, SoxR acts as a strong transcription activator of soxS promoter<sup>[1]</sup>. The sequence of this basic part is the reverse complement of <i>soxR</i> gene from <i>E. coli</i>.
+<br>SoxR protein was used to regulate the expression of taurine-producing enzymes. When the [2Fe–2S] cluster is fully oxidized, SoxR acts as a strong transcription activator of <i>soxS</i> promoter<sup>[1]</sup>. The sequence of this basic part is the reverse complement of <i>soxR</i> gene from <i>E. coli</i>.
 <br>