Team:CSU CHINA/Poster
Poster: CSU_CHINA
Poster Template
This poster template will let you create an interactive poster! The poster is divided in two parts: the visual overview on the left and the documentation on the right. The visual overview is broken down into sections that the user can click on. When a user clicks on a poster section in the visual overview, the documentation on the right will display the text and graphics associated with this section of the poster. You can find the documentation on how to use this template, as well as an example here: https://2020.igem.org/Competition/Deliverables/Poster
Cadmium contamination of water worldwide is already having a severe environmental impact, especially on crops, such as cadmium rice. In addition, cadmium contamination is likely to cause itai-itai disease and renal tubular injury, after prolonged and/or high exposure may eventually to renal failure, thus, the problem of cadmium pollution of water needs to be solved urgently. We adopt an environmentally friendly biological approach——use Synechocystis sp. PCC6803 with a clear genetic background and a certain degree of tolerance to cadmium as a chassis organism for transformation.
First of all, we translate cadmium, which is enriched on the cell wall through transporter proteins. However, this may cause photosynthesis failure, protein inactivation or oxidative stress in Synechocystis and lead to cell death, making it difficult to achieve high tolerance rate. Therefore, after transporting large amounts of cadmium ions into the cells, we accumulate heavy metal ions and prevent them from being transported out of the cells by chelating proteins. At the same time, we increase the expression of oxidoreductase to remove reactive oxygen clusters in the cells, thus increasing the growth rate of algae under cadmium ion stress. Besides, for high expression of functional proteins, We optimized the codon preferences of the algae, and analyzed the protein expression results.(Figure 1)
Cadmium contamination of water worldwide is already having a severe environmental impact, especially on crops, such as cadmium rice. In addition, cadmium contamination is likely to cause itai-itai disease and renal tubular injury, after prolonged and/or high exposure may eventually to renal failure, thus, the problem of cadmium pollution of water needs to be solved urgently. We adopt an environmentally friendly biological approach——use Synechocystis sp. PCC6803 with a clear genetic background and a certain degree of tolerance to cadmium as a chassis organism for transformation.
First of all, we translate cadmium, which is enriched on the cell wall through transporter proteins. However, this may cause photosynthesis failure, protein inactivation or oxidative stress in Synechocystis and lead to cell death, making it difficult to achieve high tolerance rate. Therefore, after transporting large amounts of cadmium ions into the cells, we accumulate heavy metal ions and prevent them from being transported out of the cells by chelating proteins. At the same time, we increase the expression of oxidoreductase to remove reactive oxygen clusters in the cells, thus increasing the growth rate of algae under cadmium ion stress. Besides, for high expression of functional proteins, We optimized the codon preferences of the algae, and analyzed the protein expression results.(Figure 1)
We extended module level from cell into the real world through this model. Based on We extended module level from cell into the real world through this model. Based on element analysis, we rebuilt the microbead and cells virtually, and predict its reaction, then get the module optimized.
Model 1: flow between environment and microbead
Model 2: flow between algae and microbead
The escape of engineered synechocystis is one of the major hazards of genetically modified organism, which may lead to different adverse effects such as water bloom and reduction of water polymorphism. Considering these risks, we designed a blue-light-controlled "toxin-antitoxin" suicide system. (Figure 2) In this system we use the RelE/RelB-toxin/antitoxin system and regulate the expression of the toxin RelE through the blue light-regulated promoter. In the presence of blue light, the regularly expressed HTH-LOV-REP blue-regulated protein will homodimerize and specifically recognize the (c120)5 sequence upstream of the blue-regulated promoter via HTH, while inhibiting the expression of toxin RelE via the REP domain. When synechocystis escaped from the blue light environment we have set up, the uninhibited blue light regulatory promoter will initiate the expression of RelE and under the effect of our amplification system, the content of RelE will increase rapidly, as a result the escaped algae will be killed. Meanwhile in order to prevent the small amount of RelE that is still expressed in the presence of blue light from harming the algae, we regularly express the antitoxin RelB to neutralize its toxin to ensure that the toxin RelE does not harm the unescaped Synechocystis sp.PCC6803.
Figure 2:Third-generation system the Blue light regulated suicide system
