Difference between revisions of "Template:UCAS-China"

DESCRIPTION

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.

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 explored in depth the relationship of art and science in the Human Practices section.

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!

DESIGN

In our work, the 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 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, an 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 which the sigma fragments activated by light sensors can combine with the constitutive expressed non-active ‘core’ fragment to form complete RNA polymerases, then activated the expression of actuators accordingly. For more information on the circuit design, see light to color.

The actuators we chose are three kinds of color protein: fluorescent protein, chromoprotein and enzyme which can produce colorful substance. 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 costs much time and effort. So how to create more colors in a reasonable and convenient way? Here we put forward a new concept—mixing color in bacterial cells! Unlike the mix of different bacterial cells which produce different colors as the previous iGEM teams have done, 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 a 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 connect the computers with 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

LIGHT TO ODOR

Our roses are colorful now, but only fragrance that makes them vivid, appealing and with the soul as a real rose. So there came our second part, light to odor, making our roses more perfect and real. We first tried to use CRISPR/Cas9 gene-editing system to knock off 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, 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 can produce various kinds of fragrance. We devoted our effort 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. Thus we can use light to control the fragrance of E.coli, and the function of our system was tested by qPCR and HPLC. (more information see Light To ODOR)

SOUND TO LIGHT

We could paint a colorful and fragrant rose through light , but it was sound that brought unique soul to the rose. To make everyone able to create his/her rose with unique soul, we developed a online software 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 stain the pictures with the random colorful dots. When the music was input, the wave of sound will be read and amplitude and frequency of the music in a period of time will be extracted. The diameter and the color of the dots varied with the amplitude and frequency of the music, and the pictures thus were painted with beautiful colors.

THE COMBINATION OF ART & SCIENCE!

As Wilde conveyed in the 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 work is the stereotype of defining art as being too selfish and far from the public and science as all reality but no emotion. We did survey on the opinions of students from science and art background, and to our surprise we found the unconventional idea of combination of art and science has been well-accepted among the young generation.

Encouraged by the public need, we interviewed many professors who is experienced in popularization of both art and science, and also communicated with artists in the AS Research Center. During this process we gradually got motivated and had a clear idea of our story to explore the junction of art and science.(more information see HP)

More than a hundred years ago, In Wilde’s story, the rose was thrown into the gutter. But today, we UCAS-China iGEMers pick the rose back again, also offer everyone the chance to create their own roses. Inspired by idealism and stirring by imagination, facilitated by scientific gene circuit and develop a practical kit, we expect our work would inaugurate a new era of art and science!