Difference between revisions of "Part:BBa K5152006"
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We co-expressed the modified MerR under a medium-strength promoter to enhance sensitivity. The cell strain we used was TOP10 <i>E. coli</i>. | We co-expressed the modified MerR under a medium-strength promoter to enhance sensitivity. The cell strain we used was TOP10 <i>E. coli</i>. | ||
− | Our goal is to develop biosensors for heavy metals that don't require special techniques or expensive equipment. Therefore, we used chromoproteins for their visible | + | Our goal is to develop biosensors for heavy metals that don't require special techniques or expensive equipment. Therefore, we used chromoproteins for their visible colours. This biosensor uses the amilCP chromoprotein, which turns cells blue in the presence of cadmium. |
Our project also examined several chromoproteins, including amilCP, cjBlue, tsPurple, eforRed, and dTomato. For more details, please refer to our wiki page. | Our project also examined several chromoproteins, including amilCP, cjBlue, tsPurple, eforRed, and dTomato. For more details, please refer to our wiki page. | ||
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<b>Cadmium Detection Functional Assay</b> | <b>Cadmium Detection Functional Assay</b> | ||
− | Our biosensor design effectively detected cadmium. After adding 200 µM cadmium (II) chloride to the culture, the cells showed visible blue | + | Our biosensor design effectively detected cadmium. After adding 200 µM cadmium (II) chloride to the culture, the cells showed visible blue colouration in the pellet after 12 hours. However, we consistently observed that extending the incubation time caused the negative control to also turn blue, indicating leaky expression. Therefore, it's important to carefully choose specific timing and conditions to avoid false positives. |
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<img src="https://static.igem.wiki/teams/5152/part-registry/17ab-merr-pcada-functional.webp" alt="100 uM Pb 12 hours" width="600"> | <img src="https://static.igem.wiki/teams/5152/part-registry/17ab-merr-pcada-functional.webp" alt="100 uM Pb 12 hours" width="600"> | ||
− | <figcaption><u>Fig. 1: Biosensor cells exposed to 200 µM cadmium (II) chloride displayed an observable blue | + | <figcaption><u>Fig. 1: Biosensor cells exposed to 200 µM cadmium (II) chloride displayed an observable blue colour in the pellets. While there's a noticeable difference, the blue colouration in the culture is less distinct.</u> </figcaption> |
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</html> | </html> |
Revision as of 00:03, 27 September 2024
MerR-pCadA cadmium sensing chromoprotein reporter device
This part was used to create a cadmium-sensing biosensor for our project, inspired by iGEM 2015 Team SCUT (BBa_K1724000).
The pCadA promoter is cadmium-activated and normally repressed by MerR, which binds mercury. In our design, we used a modified MerR (BBa_K1724001) that binds to cadmium, making the system sensitive to cadmium.
We co-expressed the modified MerR under a medium-strength promoter to enhance sensitivity. The cell strain we used was TOP10 E. coli.
Our goal is to develop biosensors for heavy metals that don't require special techniques or expensive equipment. Therefore, we used chromoproteins for their visible colours. This biosensor uses the amilCP chromoprotein, which turns cells blue in the presence of cadmium.
Our project also examined several chromoproteins, including amilCP, cjBlue, tsPurple, eforRed, and dTomato. For more details, please refer to our wiki page.
Usage and Biology
Cadmium Detection Functional Assay
Our biosensor design effectively detected cadmium. After adding 200 µM cadmium (II) chloride to the culture, the cells showed visible blue colouration in the pellet after 12 hours. However, we consistently observed that extending the incubation time caused the negative control to also turn blue, indicating leaky expression. Therefore, it's important to carefully choose specific timing and conditions to avoid false positives.
Sequence and Features
- 10COMPATIBLE WITH RFC[10]
- 12INCOMPATIBLE WITH RFC[12]Illegal NheI site found at 35
Illegal NheI site found at 58 - 21COMPATIBLE WITH RFC[21]
- 23COMPATIBLE WITH RFC[23]
- 25INCOMPATIBLE WITH RFC[25]Illegal AgeI site found at 350
Illegal AgeI site found at 452 - 1000COMPATIBLE WITH RFC[1000]