Team:SCU-China/HP/Silver

Human Practice

Education

Architects Competition of Microorganism Application

We held the Sichuan University 2016 Architects Competition of Microorganism Application: Human Microbiome in May and June. The students from Sichuan Agricultural University and University of Electronic Science and Technology of China were also invited. 209 students from Sichuan University and Sichuan Agricultural University attended the competition. After the first oral defense, 15 teams were chosen to attend the final.

The final was held in the largest lecture hall in Jiang’an Campus of Sichuan University. More than 10 professors attended it as the judges. After the final defense, one gold award, two silver award and four bronze award were issued (details listed below).

Holding the competition, we elevated the students’ understanding on human microbiome and iGEM competition and improved their ability of designing project. “This competition makes me learn more about human microbiome and iGEM competition. I hope it will be held after many years,” said a competitor.

Gold

Utilize Cell Surface Display System In E.coli

By Sing Ice Uucleation Protein to Relieve Corresponding Disease

Recent studies suggest that gut microbes are participants in atherosclerosis development. Specifically, choline, phosphatidylcholine—trimethylamine (TMA)-containing nutrients abundant in foods can serve as dietary precursors for TMA N-oxide (TMAO) generation, in mice and humans, a metabolite that accelerates atherosclerosis in animal models. Amount those trimethylamine (TMA)-containing nutrients choline accounts for the biggest part in human gut because it’s also the primary digestion products of phosphatidylcholine. Blood TMAO levels are associated with risks for both prevalent atherosclerotic heart disease and incident major adverse cardiac events in multiple independent cohorts. And, recently, trimethylamine-N-oxide (TMAO) has been identified as a novel and independent risk factor for promoting atherosclerosis (AS).TMAO-lowering interventions are, thus, of considerable interest for their potential therapeutic benefit.

Here we utilize cell surface display system in E.coli by using ice nucleation protein which is linked to a choline-binding protein to fix choline on the bacteria surface. Microencapsulated choline-binding bacteria will greatly compete with bacteria using choline to produce TMA, thus relieve corresponding disease.

Silver

Modification of Corynebacteria to Treat Body Odor

Hirus is an achromatic genetic disease which is disturbing. The sweat of Suffer is odorless before been processed by bacterium. It is reported the chemical that contributes absolutely most to the odor is E-3-methyl-2-hexenoic acid，E-3M2H, which combines with apoproteins before secretion. When catalyzed by a specific aminoacylase from Corynebacteria.sp, E-3M2H is free again and volatile. The project is to knock out the gene corresponding to the enzyme by Crispr/cas9 system. The modified bacteria will be transplant in the axilla of suffers. What’s more, we replace the carrier up taking glucose for the carrier up taking fatty acids to increase its competence in the axilla and avoid diffusion.

For there is CRISPR system in Corynebacteria in natural. We plan to introduce sequences from that enzyme as spacers of CRISPR system in Corynebacteria.sp to put an end to the regaining of the gene.

Use Quorum Sensing of E.coli

to Release Lactase to Treat Lactose Intolerance

Lactose intolerance is often caused by the lack of lactase in the small intestine mucosa, leading to dyspepsia and malabsorption of lactose. Clinical symptoms include abdominal distention, diarrhea, abdominal pain, etc. Chinese severely lack lactase, and lactose intolerance is relatively common, bringing great suffering to patients’ life.

At present the treatments of lactose intolerance are to reduce the lactose intake, to add lactase long-term, and to give probiotic products, which are not able to achieve sustainable and effective results.

To solve above problems, we propose using genetic engineering technology, transmitting plasmids carrying a lactase gene and a suicide gene into E. coli K12 strains. Patients take genetically modified strains of the bacterium orally. It produces lactase intracellular, and suicide gene regulates flora quantity at the same time. When the number of bacteria reaches the threshold, suicide mechanism will be activated, then intracellular lactase will be released to the gut.

Thus, it guarantees the proper number of bacteria in the intestines, and continuously produces lactase, achieving the goal of sustainable and effective treatment of lactose intolerance.

Bronze

Modification of Lactic Streptococci to Produce Arginine to Treat Oral Diseases

In this project, we transfer the gene segments which can code the synthesis of arginine from the corynebacterium crenatum to the lactic streptococci of which the lactate dehydrogenase has been knocked out through gene engineering, then put the modified lactic streptococci to human oral cavity so that arginine can be secreted in abundance when it’s acidic ,which is good for prevention of dental caries. Caries, one of the most common oral disease, is caused by that the cariogenic bacteria from the oral biofilm produce so much acid because of metabolism that pH declines to certain level which leads to enamel demineralization. Arginine is alkaline so it can improve the oral pH; it can increase the absorption amount of fluorine of enamel, enhance the antiacid ability of the surface of enamel and facilitate the remineralization of enamel. There is not much arginine in the mouth, but Glu, the synthesized substrate of arginine, is rich in our mouth. The lactic streptococci is a kind of oral probiotics, which can adhere to the surface of oral mucosa planting itself and develop and restrain the breeding of pathogenic bacteria. Besides, it has acid resistance and can produce bacteriocin which is totally good to oral health. We control the synthesis condition below pH 5.5 using pH control promoter, so arginine will only be secreted in abundance when it’s acidic and has a risk of dental caries.

Improvement of Intestinal Flora

to Improve Estrogen Levels in Postmenopausal Women

Due to the sharp decline of estrogen levels after menopause, female have a great tendency of uncomfortable symptoms like irritability and somnipathy, even leading to osteoporosis and cardiovascular disease. This project intends to make a product to alleviate and eliminate the symptoms above.

Recent research has demonstrated that certain enteric microorganisms have important influence on female hormone metabolism. The project will utilize macro genome sequencing and designing animal experiments to confirm the strain regulating estrogen levels significantly, and then we screen them in intestinal tract and enlarge cultivation, using the microfluidic technology made into candy (confection). By taking the candy, menopausal female can improve intestinal microbial environment to adjust estrogen levels, thereby mitigating a series of symptoms caused by sharply drop of estrogen after menopause.

Design and Application of Mask for Acne Treatment

This research is aimed at solving the acne problem, which usually appears in adolescents. When sebaceous glands secret too much grease and can’t eliminate it in time. Then the grease will block pores and the bacteria which parasite in the pore cells will propagate quickly. Especially one kind of them named Propioni-bacterium acnes, their mass propagation will induce immunoreaction, and excessive immunoreaction will lead to inflammatory. We add the gene of cecropin P5 into the yeasts’ genome, to restrain the growth of the Propionibacterium acnes and reduce the secret of inflammation factor. In order to solve the problem that the Cecropin is too big and can’t permeate through cuticle, we link Cecropin with peptide chaperon TD1 to form a fusion protein which is more capable to permeate. The existence of too much oleic acid will induce the assembly of inflammatory factor, while the supplement of linoleic acid can reduce inflame-mation.

We want to design a kind of mask which consists of culture medium and reconstructive Pichia Pastoris. The reconstructive Pichia Pastoris has gene of △12 fatty acid desaturases with strong promoter, and itsω-3 fatty acid desaturases gene will be knockout by Crispr/Cas9. Thus, this kind of P.Pastoris can convert oleic acid into linoleic acid, and secret the product.

Transform Slps to Get More Colonization Ability of Bifidobacterium

Bifidobacterium have the function of the adjustment of intestinal disorders, can prevent diarrhea, reduce constipation, have the effect of prevention and treatment of various intestinal disease. But now the bifido-bacterium in the food and drug is expensive, the utilization rate is not high in the body, causing much waste. Probiotics, on the other hand, as a kind of no side effect of drug carrier, more and more get the welcome of people, however, its colonization ability needs to be improved. We want to use genetic engineering technology, gene cloning Slps, design of controlled Slps operon gene expression, to build them into the expression vector, recombinant plasmid, electricity into a receptor in bifidobacterium, testing after transforming of bifidobacteria in vivo and in vitro resistance, adhesion and live action, in order to get more colonization ability of bifidobacterium, solve the disadvantage of low utilization rate of foreign probiotic bacteria in the body, make foreign probiotic bacteria in the body better able to play a role.

Community Class

Our team organized a community class for children to introduce our iGEM team and the microorganism on our bodies, especially on our feet. For the beginning, we listed some common microorganism, and differed the beneficial from the harmful. Next, our team gave a presentation about our iGEM project. At last, some children who behaved actively got microscopes as gifts.

The class attracted many children and their parents. In the class, kids gained the microorganism knowledge and had an initial understanding of synthetic biology which they showed a strong interest in. Some kids even said they wanted to be one of us in the future. Sincerely, we hope their dreams come true one day.

After the class, the parents and the children asked lots of questions related to genetic engineering and synthetic biology. Our team members explained to them patiently, and our project got a wide recognition.

As believed, genetic engineering is one of the most exciting areas in contemporary science and technology, and synthetic biology will definitely do more and more for our life. We hoped to do our bits to raise the children’s awareness about the subjects and encourage them to be curious in biology, particularly in genetic engineering and synthetic biology.

Teach-in for Freshmen

Right after the beginning of this semester, we held a teach-in for the freshmen in the College of Life Science of Sichuan University.

This teach-in was hosted by the team SCU_China. First, we introduced the origin of iGEM and synthetic biology in front of over 200 students who attended, then the contents of the iGEM competition (about the experiments, hardware design and modeling). We then shared our feeling about what wonderful experience iGEM brought to us, and how we practiced our ability of doing research from students ‘perspective. At last, we talked about the project of SCU_China and the audience were really interested in it. A lot of students exchanged their ideas with us after the teach-in and showed their interests.

The teach-in is a firm success, we not only introduced iGEM and synthetic biology to the freshmen, but also made a solid foundation for the future of SCU_China since many students showed their eagerness of joining us.

Survey

Interview in SCU Campus

To know the students’ knowledge of human microbiome, we surveyed in SCU campus. From the survey we found that most of them knew little about it. Questions regarding tinea pedis and related issues were also included.

The question first asked “How many microorganisms does a healthy adult have, assuming that he or she weighs sixty kilograms? “got various answers. The answer they gave varied from 1 kg to 30 kg, which were far off the correct answer. Such an interesting result showed that though the human microbiome was a hot spot, students still knew little about it. We then asked them that if they or the ones around them were troubled by tinea pedis. Unsurprisingly, many of them admitted that their daily life had been influenced by tinea pedis. They got a very feeling when they were exposed in the foot odor.

When we asked their acceptance to a biological product that can cure tinea pedis by killing bacteria and fungi to make them get rid of the foot odor, a great number of students said that they dared to use it even though it was bacteria-included, only if it really worked and had no side effects.

The Interview at Longquan Mountain

Tinea pedia, as well as the other diseases related to feet is a health problem that really arouses public attention in Sichuan. In order to increase the awareness of the importance of microorganism on our body, especially on the feet, and know more about people’s attitude to our project to improve it, our team went to Longquan Mountain to interview the local farmers and residents.

First, we had a preliminary understanding of the microorganism cognitive situation of local farmers and residents. We found that most people knew that microorganism had a great effect on our health and some of them or their friends were influenced by tinea pedis. Then we asked some questions about our project and it was surprising that most of them didn’t resist to using the insole with the bacteria in it. "I don't mind that it contains bacteria as long as it's useful,” said one of the interviewees.

Interview of PLA Cadets

For the final part of our interview, we choose the PLA Cadets in Sichuan University as our interviewees. Due to their daily training and seldom changed shoes and insoles, they may suffer from foot diseases more likely.

From our interview with the cadets, we know more about their foot health situation. Unsurprisingly, they are troubled by the foot diseases like the athlete’s foot which couldn’t be cured easily by common medicine available such as Daktarin or Mometasone Furoate gel, etc.

We introduced the knowledge about foot and our project which aims to cure the foot disease related to germs. The cadets showed a great interest and expect sincerely that our project can make them get rid of their foot problems..

Meet Up

IngenuityLab_Canada

The leader of IngenuityLab_Canada, Dawson, was born in Chengdu, China. So we have the opportunity to have a meetup in our lab. We discussed a lot about the each team and the difference between China and Canada iGEM competition attendance. This meetup lead us to cooperation later discussed.

CCiC Attendance

CCiC (Central China iGEM Consortium) is organized every year in China mainland. This year, SYSU-China and SYSU-Software organized such a huge meetup in College of Life Science of Sun Yat-sen University, Guangzhou, China. More than 20 teams attended the meetup and presented their project. SCU-China was invited this year and presented the project “Look What They’ve Done To My Shoes.” Haoqian Zhang, the finalist leader 2010 from Peking University gave us some good advice. We’re so happy that a lot of people are interested in our project.

It’s such a cool experience to meet with a lot of teams in China, including NCTU-Formosa from Taiwan. We talked a lot about the team project, the team construction and difficulties a lot with different teams. At the same time, it’s glad to travel in Guangzhou and Sun Yat-sen University.