Difference between revisions of "Team:UCAS-China/Description"

 
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<h1>DESCRIPTION:</h1>
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<h1>DESCRIPTION</h1>
  
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<img class="img-responsive img-center" width="400px;" src="https://static.igem.org/mediawiki/2018/6/64/T--UCAS-China--rose_forest.jpg">
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<p> One hundred years ago, there was a young boy who was seeking a unique rose for his beloved girl. It was a freezing winter night, and all roses had died. After a long time searching in the withered rose bush, the young boy was desperate. Touched by his true love, a nightingale, who heard and understood his wish, sang all night under the cold moonlight. Just before dawn, a rose stained with the blood of the nightingale, bloomed, bright and fragrant.
  
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<p>One hundred years ago, there was a young boy who was seeking a unique rose for his behaved girl. That was freezing winter night, all roes had died. After a long time searching in the withered rose bushed fruitlessly, the young boy was almost desperate. Touched by his true love, a nightingale, who understood his wish, sung all night under the cold moonlight. Just before dawn, a rose stained with blood of the nightingale, bloomed, bright and fragrant.
 
 
</p>
 
</p>
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<p>The nightingale, created by Oscar Wilde, built a red rose for true love out of her song under moonlight. To Wilde, the unique rose stained with blood of the nightingale is the symbol of love and true art. To us UCAS-China team, the touching story should be passed down to our generation and explained in a more scientific and interesting way with the tools of synthetic biology. Furthermore, as Wilde conveyed in the story, the barrier and combination of art and science still remain worth discussing, so we also explore in depth the relationship of art and science in the <a href= "https://2018.igem.org/Team:UCAS-China/Human_Practices
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<p>The writer Oscar Wilde, created a red rose for true love out of the nightingale’s song under moonlight.[1] To Wilde, the unique rose stained with blood of the nightingale is the symbol of love and true art. To us UCAS-China iGEM team, the touching story should be passed down to our generation and explained in a scientific and creative way using the tools of synthetic biology. Furthermore, as Wilde conveyed in the story, the barrier and combination of art and science still remain worthy of discussion, so we also explored in depth the relationship of art and science in the <a href= "https://2018.igem.org/Team:UCAS-China/Human_Practices">Human Practices section</a>.</p><br>.     
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">Human Practices section</a>.</p><br>.     
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<img class="img-responsive img-center" width="400px;" src="https://static.igem.org/mediawiki/2018/d/d4/T--UCAS-China--description2.jpg">
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<p>In our project which combining the four elements-music (the song of the nightingale), light (the moonlight), color (the stained rose) and odor (the rose fragrance), everyone is able to create his/her own with unique soul, together forming our rose forest in the junction of art and science!
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<p> Our project combines the four elements - music (the song of the nightingale), light (the moonlight), color (the stained rose) and odor (the rose fragrance). In our project every iGEMer is able to create his/her own rose with unique soul, together to form our rose forest in the junction of art and science!
 
</p>
 
</p>
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<h2>DESIGN:</h2>
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<h2>DESIGN</h2>
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<p> In our work, the E. coli need light and sound as inputs to produce color and odor as outputs. The process is mainly divided into three parts: sound to light, light to color, and light to odor. The light-color and light-odor conversions are achieved with the RGB vision system which is based on the phage RNAP system as a resource allocator. As for the sound-light conversion, we develop a software that allows users to upload their own music to generate their unique dynamic pictures, with which people can color and ensoul their own roses.
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<img class="img-responsive img-center" style="width:calc(35vw);" src="https://static.igem.org/mediawiki/2018/f/fa/T--UCAS-China--description3.jpg">
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<p>   In our project, E. coli needed light and sound as inputs to produce color and odor as outputs. The process was mainly divided into three parts: sound to light, light to color, and light to odor. The light-color and light-odor conversions were achieved with the RGB system[2] which was based on the phage RNAP system as a resource allocator. As for the sound-light conversion, we developed a software that allowed users to upload their own music to generate their unique dynamic pictures, with which people could color and ‘ensoul’ their own roses.
 
</p><br>
 
</p><br>
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<h2>LIGHT TO COLOR</h2>
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<img class="img-responsive img-center" style="width:calc(35vw);" src="https://static.igem.org/mediawiki/2018/a/ab/T--UCAS-China--description4.jpg">
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<p> Firstly, we introduced the RGB system to stain our rose using light. The RGB system mainly consists of four modules: a sensor array, circuits, a resource allocator and  actuators. The sensor array combines 3 light sensors, Cph8*, YF1 and CcasR, which can respond to lights of different wavelengths. CcasR can sense and be switched on by green (535nm) light. Cph8* is switched off by red (650nm) light, while YF1 is switched off by blue (470nm) light. </p><br>
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<img class="img-responsive img-center" style="width:calc(45vw);" src="https://static.igem.org/mediawiki/2018/2/2b/T--UCAS-China--description5.jpg">
  
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<p>The light control system mainly consists of 3 subsystems, a “sensor array”, an “output array” and a “signal transit”.</p><br>
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<p> To activate gene expression, the signals from the red- and blue- light sensors need to be inverted, which is done by connecting them to NOT gates in circuits.
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<p>Firstly, the “sensor array” combines 3 sensors, Cph8* (asterisk), YF1 and CcaSR, which could be activated predominantly by red, blue and green light. These optogenetic tools enables our E. coli to response to light of different wavelengths respectively.</p><br>
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<p> The resource allocator which connects the circuits and actuators, is based on a split-RNA polymerase system. In the system, the sigma fragments activated by light sensors can combine with the constitutively expressed non-active ‘core’ fragment to form complete RNA polymerases, then activates the expression of actuators accordingly. For more information on the circuit design, see <a href= "https://2018.igem.org/Team:UCAS-China/LightToColor"> LIGHT TO COLOR  </a>.</p><br>. 
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<h2>Why did we focus on diagnostics?</h2>
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<p>The actuators we chose were three kinds of color protein: fluorescent protein, chromoprotein and enzyme which can produce colorful products. Although more and more fluorescent proteins and chromoproteins are edited to generate more and more colors, the number of colors produced by organisms is still limited by the number of the kinds of proteins. Once a new color is needed, researchers have to modify the chromophores of the proteins, which takes much time and effort.
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</p><br>
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<p>So how do we create more colors in a reasonable and convenient way? Here, we put forward a new concept—mixing color into bacterial cells! Unlike the mix of different bacterial cells which produce different colors as the previous iGEM teams have done[4], we used tandem expression and RGB system to control the ratios of the expression of different colors in bacterial cells, to achieve mixing color in bacterial cells, and stain our roses with more bright colors.  
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</p><br>
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<p> We built hardware to generate lights with smooth distribution on the plates and controlled intensity, to activate our system to produce predictable colors. Our final hardware is designed and built to illuminate our bacteria on the plates, with the help of a projector, to achieve the interaction between users and our E.coli. More information see <a href= "https://2018.igem.org/Team:UCAS-China/Hardware"> HARDWARE</a>.</p><br>.
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<h2>LIGHT TO ODOR</h2>
  
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<p>Very early on, we each came up with an idea for our iGEM project and presented it to the group. You can see some of these on our <a href= "https://2017.igem.org/Team:Oxford/InitialIdeas">Initial Ideas page</a>.</p><br>
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<p> Our roses are colorful now, but only with added fragrance can the rose bloom  more vivid, appealing and with a soul as a real rose. So this is our second part, light to odor, making our roses more soulful and real. We first tried to use CRISPR/Cas9 gene-editing system[5] to knock out the original gene of E. coli producing smell to prevent E. coli from giving off a nasty and unpleasant smell. Then based on the light-control system, we changed the actuators with genes which could produce various kinds of odors.</p><br>
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<p>We carried out a public survey in the UK, where more than half of the 200 surveyed wanted a synthetic biology solution for disease diagnosis. You can read more about our surveys on our <a href= "https://2017.igem.org/Team:Oxford/HP/Silver">Silver Human Practices page</a>.<br>
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<br><p>We identified a gap in the field of rapid, point-of-care diagnostics which arises when antibody-based technologies cannot be used, for example diagnosis of diseases in infants or immunocompromised patients. As a result, we decided to use the flexibility and versatility of synthetic biology to design a platform technology which addresses these issues.
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<p>The inherent unpleasant odor of E. coli comes from indole produced naturally in the cells’ metabolic process. In the L-tryptophan degradation pathway, Tryptophanase, encoded by tnaA gene[6], degraded L-tryptophan of indole, which produces the odor in high concentration.</p><br>
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<p>L-tryptophan + H2O = indole + pyruvate + NH3. (The enzyme needs Co-factor: pyridoxal 5'-phosphate)
 
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</p><br>
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<p>We first tried to knock out the tnaA gene in the genome of E. coli, then we replaced the actuators in the RGB system with genes which could produce various kinds of fragrance. We devoted ourselves to introducing diversified odor to make our roses not only vivid ones with traditional flower fragrance, but unique ones with more kinds of odor like lemon and rain[7]. Thus we can use light to control the fragrance of E.coli, and the function of our system was tested by HPLC. (See <a href= "https://2018.igem.org/Team:UCAS-China/LightToOdor">LIGHT TO ODOR</a>).</p><br>
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<h2>SOUND TO LIGHT</h2>
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<img class="img-responsive img-center" style="width:calc(35vw);" src="https://static.igem.org/mediawiki/2018/7/7b/T--UCAS-China--description7.jpg">
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<p>We could paint a colorful and fragrant rose with light , but it was sound that brought a unique soul to the rose.  To create his/her rose with a unique soul, we developed an online software—Orpheus—to convert music into unique colorful pictures. The users could choose their music or their own voice, and the pictures that they want to ensoul, to color the pictures with random colorful dots. When the music is input, after a specified time, the sound waves will be read and the amplitude and frequency of the music will be extracted. The diameter and the color of the dots vary with the amplitude and frequency of the music, and the pictures thus they are painted with beautiful colors. (see <a href= "https://2018.igem.org/Team:UCAS-China/Software">SOUND TO LIGHT</a>).</p><br>
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<img class="img-responsive img-center" style="width:calc(35vw);" src="https://static.igem.org/mediawiki/2018/c/ce/T--UCAS-China--description8.jpg">
  
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<h2>What is Chagas disease?</h2>
 
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<p>Our cell-free diagnosis kit is designed to diagnose Chagas disease in its acute phase using a simple blood test. Chagas disease is a neglected tropical disease endemic to Latin America that impacts 6-7 million people, of whom 95% lack sufficient diagnosis or treatment. We decided to focus our efforts on designing a diagnostic for congenital Chagas disease, since current point-of-care diagnostics cannot be used to detect Chagas disease in infants. Current treatments using benznidazole and nifurtimox are almost 100% effective if given shortly after the onset of the acute phase. However, lack of diagnosis leads to the onset of the chronic phase, which causes irreversible pathological consequences to the heart, digestive system, and nervous system. We hope to make a positive contribution towards this cause with our project. </p><br>
 
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<p> You can read more about this on our <a href= "https://2017.igem.org/Team:Oxford/Chagas_Disease">Chagas disease page</a>.</p><br>
 
  
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<h2>THE COMBINATION OF ART & SCIENCE!</h2>
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<p> As Wilde conveyed in his story, the barrier and combination of art and science still remain worth discussing, so we explored in depth the relationship of art and science in the Human Practices section. One prime barrier of outstanding art and science is the stereotype of defining art as being too selfish and far from the public and science as only about reality with no emotion. We surveyed university students from science and art backgrounds, and to our surprise we found the unconventional idea that the integration of art and science has been well-accepted among the younger generation.</p><br>
  
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<h2>What is our solution?</h2>
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<p> Encouraged by our survey , we interviewed many university professors who are experienced in popularization of both art and science, and also communicated with artists in the AS Research Center. During this investigative interview process we gradually got motivated and had a clearer idea of our story to explore the junction of art and science.(see <a href= "https://2018.igem.org/Team:UCAS-China/Human_Practices">HUMAN PRACTICES</a>).</p><br>
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<p>We have designed two systems - one DNA based and one protein-based - to detect a protease, cruzipain. Cruzipain is produced and secreted  by <em>T. cruzi</em>  in the blood and has a specific cleavage sequence, which is ideal for the input. Our systems have bivalirudin as the output for both methods. Bivalirudin is a small peptide that acts as an anticoagulant. Therefore if bivalrirudin were produced in response to the presence of cruzipain, the blood would be inhibited from clotting. These systems are designed to be cell-free and freeze-dried to ensure safety and ease of transport, before being added to a sample of blood.</p><br>
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<p>For our DNA-based system, we have designed a TetR molecule with a cleavage site for TEV protease. Our TetR will start bound to its DNA operator, repressing the production of an output protein. When it is cleaved by TEV, repression is relieved, and the reporter produced.</p><br>
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<p>More than a hundred years ago, in Wilde’s story, the rose was thrown into the gutter. But today, we UCAS-China iGEMers have picked the rose back up from the gutter, to offer everyone the chance to create their own rose. Inspired by idealism and stirred by imagination, facilitated by scientific gene circuits we develop a practical kit expecting that our work will inaugurate a new era of art and science further inspiring young scientists for future generations. </p><br>
  
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<p>For our protein-based system, we have designed an amplificatory protein circuit encased in outer membrane vesicles (OMVs). Both our input (cruzipain) and our intermediate output (TEV protease) are proteases. The amplification components of our system is a split TEV protease, the two halves of which are made accessible to dimerise in the presence of cruzipain. Upon dimerisation, the protease is activated and can go on to activate more of itself in an amplificatory positive feedback loop. Active TEV protease can then cleave and release bivalirudin, which acts as the <a href = "https://2017.igem.org/Team:Oxford/Design#C3">reporter</a> of our system by inhibiting blood clotting.</p><br>
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<h2>References</h2>
  
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<p>[1]Oscar Wilde, 1995, Happy Prince and Other Tales. Everyman's Library, 96</p>
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<p> You can read more about this on our <a href= "https://2017.igem.org/Team:Oxford/Design">Design page</a>.</p>
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<h2>What is our strategy?</h2>
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<h3>Wet Lab</h3>
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<p>For our DNA-based system, we characterised the pTet + eYFP part using fluorescence microscopy and plate reading, which showed that TetR can bind to the pTet and repress the output fluorescence significantly. This part has a carefully picked ribosome binding site and promoter strength to optimise our system for minimal false positives and negatives when eYFP is replaced with TEV protease production. Hence it was highly important to detect how repression was relieved when Anydrotetracyline(ATC) was introduced, which acts on TetR.</p><br>
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<p>The sfGFP+Quencher was characterised for our OMV system. This part was critical to identify if sfGFP (GFP modified to fold in the periplasm) can be quenched by a quenching peptide linked with a protease specific cleavage sequence. We tested the functionality and sensitivity of the part to TEV protease through a double transformation of the part and TEV plasmids. Plate reader and fluorescence microscopy on this part identified that the Quencher can quench sfGFP fluorescence and that quenching can be relieved by introducing the TEV protease.</p><br>
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<p> You can read more about this in our <a href= "https://2017.igem.org/Team:Oxford/Overview_Wet_Lab">Wet Lab section</a>.</p>
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<h3>Real-world perspectives</h3>
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<p>Our project has been guided throughout by input from experts in Latin America and medical professionals in the UK. Conversations with the public during our outreach activities also helped us to consider perspectives around synthetic biology outside the lab. You can read more about this on our <a href= "https://2017.igem.org/Team:Oxford/HP/Gold_Integrated">Gold & Integrated Human Practices page</a> and <a href= "https://2017.igem.org/Team:Oxford/Engagement">Education & Public Engagement page</a>.</p><br>
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<p>Consultation with relevant stakeholders, including HeLEX (Centre for Health, Law and Emerging Technologies), InSIS (Institute for Science Innovation and Society) and numerous experts worldwide, has helped to inform ethical and social considerations relevant to our project. These consultations have directly fed back into our applied design to enable a bedside-to-bench approach helping us to design and prototype a diagnostic kit for Chagas disease which is easy-to-use, cheap to manufacture and has minimal risk to the environment. <a href= "https://2017.igem.org/Team:Oxford/Applied_Design">You can read more about this on our Applied Design page</a>.</p><br>
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<p>To support the integration of our device into existing healthcare systems, our dialogue with HeLEX inspired us to create a policy proposal to address gaps in regulation present in current infrastructure.</p><br>
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<a href="https://2017.igem.org/Team:Oxford/Chagas_Public_Policy"><img class="img-responsive img-center" width="200px;" src="https://static.igem.org/mediawiki/2017/9/98/T--oxford--chagas_disease--button.png"></a><br>
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<p>Our cell-free design has been inspired by consultation with Dr Keith Pardee. Combining this with our discussions about safety with Piers Millet and HeLEX, we designed our parts for the wet lab with this in mind and produced a report outlining the barriers faced by cell-free technology. We hope this will prove useful for future iGEM teams using cell-free technology.</p><br>
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<a href="https://2017.igem.org/Team:Oxford/Cell_Free_Report"><img class="img-responsive img-center" width="200px;" src="https://static.igem.org/mediawiki/2017/c/ca/T--oxford--cellfreereport.png"></a>
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<p> Modelling was an inseparable part of our design process: it allowed us to quickly test our theoretical designs and identify key design parameters that could improve our design. We worked closely with experts throughout developing our models. Collaborations have allowed us to refine our methodology by applying it to the different systems of other teams, inspiring us to document it to help future teams. <a href= "https://2017.igem.org/Team:Oxford/Model">You can read more about this in our Modelling section</a>.</p><br>
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<p>We were able to model the impact our diagnostic would have on the epidemiology of Chagas disease in Bolivia by working closely with Professor Michael Bonsall (a mathematical biologist) and Dr Yves Carlier (a Chagas epidemiologist) to create a disease model that we hope to publish later this year. <a href= "https://2017.igem.org/Team:Oxford/Disease_Model">You can read more about this on our Disease Modelling page</a>.</p><br>
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<p>To develop our system into something which can undergo clinical trials and hopefully become a successful product, we have a vision for the experiments that need to be performed. These are detailed at the end of our Results pages - <a href= "https://2017.igem.org/Team:Oxford/Results_DNA">DNA-based</a> and <a href= "https://2017.igem.org/Team:Oxford/Results_Protein">Protein-based</a>.</p><br>
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<p>For our DNA-based system, we envision the progression from a proof-of-concept system to gradually introducing each ‘real’ components, and testing that this does not perturb our system and corroborates our modelling. Additionally, we wish to check the efficacy of different lysates and the freeze-drying process.</p><br>
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<p>For our protein-based system, the aim is to first express our components in outer membrane vesicles, before trialing methods of lysing the OMVs and assaying the efficacy of the split-TEV protease molecule.</p><br>
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<h3>Future visions for our kit</h3>
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<p>We have designed a software tool to facilitate further applications of our project, as our system may be applied to a range of diseases. This is an open-source tool so that researchers may add to a growing database of pathogens and specific protease cleavage sites.</p><br>
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<p>As our kit is modular, it can be easily and cheaply adapted to diagnose different diseases: the cost of changing the disease is then only the input block, not also the output block. Our vision for the future is that a streamlined manufacturing process can be established for rapid development of new diagnostic modules as more specific proteases are characterised and validated as biomarkers.</p><br>
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<h2>References</h2>
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<p>Courbet A., Renard E., and Molina F. 2016 Bringing next‐generation diagnostics to the clinic through synthetic biology. EMBO Mol Med 8: 987–991</p>
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<p>[2] Fernandez-Rodriguez J, Moser F, Song M, et al. Engineering RGB color vision into Escherichia coli[J]. Nature Chemical Biology, 2017, 13(7):706-708.</p>
  
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<p>Slomovic S., Pardee K., and Collins J.J. 2015 Synthetic biology devices for in vitro and in vivo diagnostics. Proc Natl Acad Sci USA 112: 14429–14435.</p>
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<p>[3] Segallshapiro T H, Meyer A J, Ellington A D, et al. A 'resource allocator' for transcription based on a highly fragmented T7 RNA polymerase.[J]. Molecular Systems Biology, 2014, 10(7):742.</p>
  
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<p>Wehr, M. C. et al. 2006 ‘Monitoring regulated protein-protein interactions using split TEV’, Nat Meth, 3(12), pp. 985–993. Available at: http://dx.doi.org/10.1038/nmeth967.</p>
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<p>[4] https://2010.igem.org/Team:KIT-Kyoto</p>
  
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<p>Alves, N. J. et al. 2016 ‘Protecting enzymatic function through directed packaging into bacterial outer membrane vesicles’, Scientific Reports. Nature Publishing Group, 6(1), p. 24866. doi: 10.1038/srep24866.</p>
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<p>[5] Cong L, Zhang F. Genome Engineering Using CRISPR-Cas9 System[J]. Methods in Molecular Biology, 2015, 1239(11):197.</p>
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<p>[6]Li G, Young K D. Indole production by the tryptophanase TnaA in Escherichia coli is determined by the amount of exogenous tryptophan[J]. Microbiology-sgm, 2013, 159(2):402-410.</p>
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<p>[7] https://2014.igem.org/Team:Paris_Bettencourt</p>
  
  

Latest revision as of 07:27, 3 December 2018

DESCRIPTION

One hundred years ago, there was a young boy who was seeking a unique rose for his beloved girl. It was a freezing winter night, and all roses had died. After a long time searching in the withered rose bush, the young boy was desperate. Touched by his true love, a nightingale, who heard and understood his wish, sang all night under the cold moonlight. Just before dawn, a rose stained with the blood of the nightingale, bloomed, bright and fragrant.

The writer Oscar Wilde, created a red rose for true love out of the nightingale’s song under moonlight.[1] To Wilde, the unique rose stained with blood of the nightingale is the symbol of love and true art. To us UCAS-China iGEM team, the touching story should be passed down to our generation and explained in a scientific and creative way using the tools of synthetic biology. Furthermore, as Wilde conveyed in the story, the barrier and combination of art and science still remain worthy of discussion, so we also explored in depth the relationship of art and science in the Human Practices section.


.

Our project combines the four elements - music (the song of the nightingale), light (the moonlight), color (the stained rose) and odor (the rose fragrance). In our project every iGEMer is able to create his/her own rose with unique soul, together to form our rose forest in the junction of art and science!

DESIGN

In our project, E. coli needed light and sound as inputs to produce color and odor as outputs. The process was mainly divided into three parts: sound to light, light to color, and light to odor. The light-color and light-odor conversions were achieved with the RGB system[2] which was based on the phage RNAP system as a resource allocator. As for the sound-light conversion, we developed a software that allowed users to upload their own music to generate their unique dynamic pictures, with which people could color and ‘ensoul’ their own roses.


LIGHT TO COLOR

Firstly, we introduced the RGB system to stain our rose using light. The RGB system mainly consists of four modules: a sensor array, circuits, a resource allocator and actuators. The sensor array combines 3 light sensors, Cph8*, YF1 and CcasR, which can respond to lights of different wavelengths. CcasR can sense and be switched on by green (535nm) light. Cph8* is switched off by red (650nm) light, while YF1 is switched off by blue (470nm) light.


To activate gene expression, the signals from the red- and blue- light sensors need to be inverted, which is done by connecting them to NOT gates in circuits.


The resource allocator which connects the circuits and actuators, is based on a split-RNA polymerase system. In the system, the sigma fragments activated by light sensors can combine with the constitutively expressed non-active ‘core’ fragment to form complete RNA polymerases, then activates the expression of actuators accordingly. For more information on the circuit design, see LIGHT TO COLOR .


.


The actuators we chose were three kinds of color protein: fluorescent protein, chromoprotein and enzyme which can produce colorful products. Although more and more fluorescent proteins and chromoproteins are edited to generate more and more colors, the number of colors produced by organisms is still limited by the number of the kinds of proteins. Once a new color is needed, researchers have to modify the chromophores of the proteins, which takes much time and effort.


So how do we create more colors in a reasonable and convenient way? Here, we put forward a new concept—mixing color into bacterial cells! Unlike the mix of different bacterial cells which produce different colors as the previous iGEM teams have done[4], we used tandem expression and RGB system to control the ratios of the expression of different colors in bacterial cells, to achieve mixing color in bacterial cells, and stain our roses with more bright colors.


We built hardware to generate lights with smooth distribution on the plates and controlled intensity, to activate our system to produce predictable colors. Our final hardware is designed and built to illuminate our bacteria on the plates, with the help of a projector, to achieve the interaction between users and our E.coli. More information see HARDWARE.


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LIGHT TO ODOR

Our roses are colorful now, but only with added fragrance can the rose bloom more vivid, appealing and with a soul as a real rose. So this is our second part, light to odor, making our roses more soulful and real. We first tried to use CRISPR/Cas9 gene-editing system[5] to knock out the original gene of E. coli producing smell to prevent E. coli from giving off a nasty and unpleasant smell. Then based on the light-control system, we changed the actuators with genes which could produce various kinds of odors.


The inherent unpleasant odor of E. coli comes from indole produced naturally in the cells’ metabolic process. In the L-tryptophan degradation pathway, Tryptophanase, encoded by tnaA gene[6], degraded L-tryptophan of indole, which produces the odor in high concentration.


L-tryptophan + H2O = indole + pyruvate + NH3. (The enzyme needs Co-factor: pyridoxal 5'-phosphate)


We first tried to knock out the tnaA gene in the genome of E. coli, then we replaced the actuators in the RGB system with genes which could produce various kinds of fragrance. We devoted ourselves to introducing diversified odor to make our roses not only vivid ones with traditional flower fragrance, but unique ones with more kinds of odor like lemon and rain[7]. Thus we can use light to control the fragrance of E.coli, and the function of our system was tested by HPLC. (See LIGHT TO ODOR).


SOUND TO LIGHT

We could paint a colorful and fragrant rose with light , but it was sound that brought a unique soul to the rose. To create his/her rose with a unique soul, we developed an online software—Orpheus—to convert music into unique colorful pictures. The users could choose their music or their own voice, and the pictures that they want to ensoul, to color the pictures with random colorful dots. When the music is input, after a specified time, the sound waves will be read and the amplitude and frequency of the music will be extracted. The diameter and the color of the dots vary with the amplitude and frequency of the music, and the pictures thus they are painted with beautiful colors. (see SOUND TO LIGHT).


THE COMBINATION OF ART & SCIENCE!

As Wilde conveyed in his story, the barrier and combination of art and science still remain worth discussing, so we explored in depth the relationship of art and science in the Human Practices section. One prime barrier of outstanding art and science is the stereotype of defining art as being too selfish and far from the public and science as only about reality with no emotion. We surveyed university students from science and art backgrounds, and to our surprise we found the unconventional idea that the integration of art and science has been well-accepted among the younger generation.


Encouraged by our survey , we interviewed many university professors who are experienced in popularization of both art and science, and also communicated with artists in the AS Research Center. During this investigative interview process we gradually got motivated and had a clearer idea of our story to explore the junction of art and science.(see HUMAN PRACTICES).


More than a hundred years ago, in Wilde’s story, the rose was thrown into the gutter. But today, we UCAS-China iGEMers have picked the rose back up from the gutter, to offer everyone the chance to create their own rose. Inspired by idealism and stirred by imagination, facilitated by scientific gene circuits we develop a practical kit expecting that our work will inaugurate a new era of art and science further inspiring young scientists for future generations.


References

[1]Oscar Wilde, 1995, Happy Prince and Other Tales. Everyman's Library, 96

[2] Fernandez-Rodriguez J, Moser F, Song M, et al. Engineering RGB color vision into Escherichia coli[J]. Nature Chemical Biology, 2017, 13(7):706-708.

[3] Segallshapiro T H, Meyer A J, Ellington A D, et al. A 'resource allocator' for transcription based on a highly fragmented T7 RNA polymerase.[J]. Molecular Systems Biology, 2014, 10(7):742.

[4] https://2010.igem.org/Team:KIT-Kyoto

[5] Cong L, Zhang F. Genome Engineering Using CRISPR-Cas9 System[J]. Methods in Molecular Biology, 2015, 1239(11):197.

[6]Li G, Young K D. Indole production by the tryptophanase TnaA in Escherichia coli is determined by the amount of exogenous tryptophan[J]. Microbiology-sgm, 2013, 159(2):402-410.

[7] https://2014.igem.org/Team:Paris_Bettencourt