Inspiration

Our project's initial design is somewhat different from the small peptide delivery system now.
We were initially inspired by the personal experience of our team member. She and her family suffered from hereditary obesity and diabetes. Family members with type I diabetes needed regular insulin injections and medication, while members with type II fortunately didn’t need insulin injections but also needed regular medication. Patients with type I diabetes suffer from acute diseases when blood sugar rises sharply like sugar foot. From the personal experience of her family member, the pain was like “countless ants gnawing on the legs and feet”. Patients with type II diabetes would be under the pressure of chronic diseases like insulin resistance, polycystic ovary syndrome, etc. What’s more, their daily lives were seriously bothered. They have to suffer from painful injections, have to take medication at a high frequency, have to tolerate the side effects of the medicine, have to lose weight in a short period, and have to strictly control their diet.
“It would be great if a product could alleviate these situations.” With this idea in heart, we began the background research.

Background Research

After a thorough investigation, we found that the problem didn't only exist in the individual cases. Now, diabetes and obesity have become important global health problems. According to the statistics of the World Health Organization, about 422 million people worldwide suffer from diabetes, and more than 4 million people die each year due to being overweight or obese. Once diabetes and obesity are formed, they will become a chronic and progressive disease. At present, there is no universally recognized so-called "cure method". Both obese and diabetes patients need lifelong intervention.

Initial Design

A sustainable blood sugar-reducing bacteria

After ensuring our idea was worth further development, we got down to our initial design. Our initial design included 4 modules: Sensing, Secretion, Adhesion, and Biosafety. The last three modules are similar to the final design. Only the sensing module was different. In the sensing module, we chose the Trz-OmpR system. It can sense the increasing intestinal sugar and activate the synthesis of small peptides.

Design Iteration

Focusing on the delivery system

After conducting a full scale literatures review, we found that the threshold of our glucose sensing system Trz-OmpR is unable to meet the requirement of our project. This would burden our concept-proving. To solve this problem, We had a thorough discussion with our advisors Jincheng Wang and Guoming Gao. During the discussion, Gao believed that our delivery module had broad application prospects since small peptides could be changed. He suggested that we should not limit ourselves to lowering blood sugar, but to expand our project into a small peptide delivery system.

After the discussion, we reviewed the literature and chose small peptides QEP and AQ as our delivery targets, and temporarily put down the sensing system. Following 2 months of development, we discussed our project with our instructors Lei Bai and Zhixiong Xie. They acknowledged the feasibility of our project and provided valuable suggestions. Especially, they considered that our delivery system may be affected by other proteins in the outer membrane system, which required further research.

Experiment design inquiry

After the project design was refined, we started with our experiment. To ensure that our experimental design was feasible, we had conversations with several professors from the School of Life Sciences. (Check details in the Communication page) Initially, we discussed with Professor Fei Gan, who majored in synthesis biology. While acknowledging the creative design, she also pointed out some problems in the plasmid construction. Specifically, she claimed that the T7 promoter is a strong promoter and the lac operator is leaking. This might cause the formation of inclusion and affect the normal function of proteins. Following her instructions, we improve our experiment design like changing the promoter and decreasing the induction temperature. See our Result page and Engineering page.

At the same time, we communicated with Professor Yingliang Wu, who researched the structure of protein. He recommended that we use mass spectrum technology and HPLC technology if we aimed to verify the feasibility of enzymatic cleavage.

We also discussed with our advisor Jincheng Wang throughout the experimental cycle. Additionally, we collaborate with team CUG-China on the experimental design. See our Collaboration page

Public Evaluation and Market Research

clinical values

As the project became increasingly mature, we sought opinions from stakeholders to assess the potential of our project. We had an all-around public evaluation and market research. (You can check the complete record on our communication page) We initially had a discussion with doctor Mei Ye, who specialized in gastroenterology. From her professional perspective, she claimed that reducing the frequency of medication for patients is beneficial, which would increase patients’ life quality. What's more, she recommended we seek advice from professors in the College of Pharmacy to have more professional feedback.

Following the guidance of Doctor Ye, We had a conversation with a professor from the School of Pharmacy, Changjiang Dong. Professor Dong, who also conducted research on Lpp'OmpA, acknowledged the overall design of our project. Meanwhile, he offered possible small peptides which could be applied in the future.

At the same time, we also had a conversation with Gastroenterologist Xingxing He. While acknowledging our delivery system, he also put forward some constructive suggestions. For example, he doubted the function of small peptides. The choices of our small peptides needed to be under thorough consideration and research in the future application.

Apart from offline conversations, we also conducted various online discussion with doctors across the country and abroad to enhance the scope of the project. We first had a conversation with pediatrician Liting Wang who works in Guangxi. She acknowledged that our delivery system was beneficial to the children since children were unwilling to take medication frequently and afraid of invasive injections. She also suggested that we increase the variety of products, which echoed with our small peptides' interchangeable properties. Creating a series of engineered bacteria for different diseases would be easier to promote, and the cost of a single product would also be lower. At the same time, this would reduce the use of other drugs and make it easier for people to accept.

commercial value

Not only did we focus on the clinical value of our project, but we also paid attention to the commercialization of our project. Therefore, we had conversations with various practitioners in biotech companies. Initially, we had a conversation with Mr.Gu, the deputy general manager of Kangyuan Bochuang Biotechnology (Beijing) Co. Ltd. He pointed out that if we wanted to commercialize our project, an extra survey and experiment on the cost and the choice of slow-release embedding material are needed. Following his advice, we conducted thorough research on the embedding material and designed our product form. See the application page.

Meanwhile, we visited Hunan Bizu Biotech Company and communicated with Mr.Jiang, the leader of the company. He recommended that we go for the food-grade market, especially the dual-purpose health supplement market. He also noted that in the future, we should focus on the continuous expression of the small peptides.

To have a broader range of investigations, we had an online conversation with Ms. Pei Jun Chai. She is the leader of one of the research teams in CytoHealth, Malaysia's pioneer Research and Development Bioprocessing company in the field of Regenerative Medicine and Immunotherapy. While acknowledging our project, she also claimed that in future applications, we should consider the product's form, which will affect the efficiency of our products.

From the investigations above, we assess the feasibility, public feedback, and application potential of our project. This will guide us in refining our project and getting one step closer to the final product.

Investigating Future Prospects

Alternative Uses

When the project is about to be completed, We hope to broaden the application direction of our project, not only restricted to the probiotic bacteria. we discussed this with preventive medicine doctor Wendy Tan, who worked in Malaysia. While acknowledging our project's design, she advised us to pay more attention to how to release small peptides slowly in the future. She also proposed that vaccines can be a potential application for our project. In some new types of vaccines, peptide molecules can be used as carriers for viral proteins to be delivered into the body, thereby introducing viral proteins as pathogens and stimulating the immune system to respond. This might offer inspiration to next year's WHU-iGEM team.

More than integrated human practice

education, communication, and collaboration

During the whole process of human practice, we found that even though specialists and experts in this industry might lack the knowledge of synthetic biology. For example, doctor Ye thought it novel to use an engineered bacteria to reduce blood sugar and work as a nutrient supplement. Therefore, we believe that bringing synthetic biology into the public is necessary. We spared no efforts to publicize people of all ages and all regions. You can see our efforts in promoting the concepts and advantages of synthetic biology on the Education, Communication, and Collaboration page.

References