Team:Nanjing-China/Demonstrate
Overview
At the very beginning of our project, we expected to design three novel gas sensing pathways and develop these pathways further into portable biosensors. Now we have successfully constructed and tested our novel pathways under real conditions. Our key achievements are exhibited in the following list:
• Each pathway has showed significant fluoresence, induced by corresponding gas molecules
• Each pathway has demonstrated good selectivity among a series analogs
• The recombinant E. coli for formaldehyde detection has successfully expressed visible fluoresence proteins, which exhibits apparent redness compared to the blank control
• We have designed a portable device to hold our recombinant E. coli, which is suitable for on-site detection and monitoring. Click the link to see more information about our device.
We have designed a formaldehyde sensor sequence, which is a new part of our team . The part works as expected and apparent redness is shown. The fluoresence intensity increas with the concentration of formaldehyde in a linear model from 300mmol to 600mmol. |
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Figure 1.Fluorescence measurement of E.coli cells containing the formaldehyde-induced RFP expression plasmid after gradient concentrations of formaldehyde induction and re-suspended in PBS buffer(pH7.4) |
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| It is worth to be mentioned that the team OUC help us demonstrate the result. | ||
 Figure 2. Influence of Formaldehyde Induce Time on Fluorescence Expression |
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As to the hydrogen sulfide sensor, we also designed a whole-cell biocatalytic system, displaying the concentration of hydrogen sulfide by the compound’s influence on specific genes’ expression in modified E.coli. In our design, we use red fluorescent protein as the indicator.When hydrogen sulfide exits, the gene transcription is activated, and the bacteria turns red. In the experiment, we proved that the sequence worked well and was useful to detect hydrogen sulfide |
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Figure 3.a)RFP responsiveness of the detector system. |
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We have designed and constructed a composite hydrogen-sensing full length sequence and added gfp at the end to indicate the presence of hydrogen. When the amount of hydrogen goes to a higher level, Fluorescence intensity increases apparently. The sequence was a good detecter in the lab work. | |
Figure 4. Influence of H2 concentration on fluorescence expression |
Address
Life Science Department
#163 Xianlin Blvd, Qixia District
Nanjing University
Nanjing, Jiangsu Province
P.R. of China
Zip: 210046
nanjing_china@163.com
Social media
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iGEM Nanjing-China@nanjing_china
