Team:Tianjin/Human Practice

From 2014.igem.org

Revision as of 14:10, 17 October 2014 by Poison (Talk | contribs)

Team:Tianjin2014/Safety

image igem

 

 

 

Transf ibre

 

Welcome to Team Tianjin!


①Weekly Newsletter

In order to know more about iGEM teams all around the world and enhance the cooperation among us, we have joined the Weekly Newsletter launched by Xiamen University and become one of the first teams to collaborate with them on this activity.

The newsletter usually has two major parts: project update and team stories. We should be writing about one of the parts every two weeks. What’s more, we share funny stories about our experiments and members. Through this activity, all the teams will be able to keep better record of their own projects, gain feedback from their peers and get to know other young synthetic biologists.

②A Nationwide Questionnaire

In order to investigate the spread and uptake of synthetic biology and IGEM competition in universities, we made a survey on the internet, through a wide-spread and professional platform for online questionnaire survey, Questionnaire star. We promote our questionnaire within the scope of all colleges in China as far as possible. According to the investigation, students coming from hundreds of schools have participated in the survey, including not only high school and undergraduate students, but also graduate students. So we can roughly believe that the results are authentic.

According to our results, we can see that the great majority of the respondents are undergraduate students, 1.24% of them are high school students and 0.62% are graduate students. There are also 1.86% staffs and 3.73% other people. On the other hand, 52.8% of them are men while 47.2% of them are women.

How many people know about the concept of synthetic biology? We are very pleased to find 40.37% respondents answered “yes”. As for the question, “Do you know some applications of synthetic biology in our contemporary life?” 44.1% people illustrate that synthetic biology has not yet entered their lives. 52.17% said they have their own?? comprehension; synthetic biology has been involved in many areas in life. We can see that only 3.73% people understand synthetic biology very well; synthetic biology has got great achievements in pharmaceutical, bio-energy, medical and many other fields. Faced with safety issues of synthetic biology, 40.37% people indicate that they would follow scientific principles to support the development of synthetic biology. While 55.28% people support precautionary principle, emphasizing the necessity to improve the supervision mechanism. 4.35% showed an attitude that they do not care the safety problem, they will use as long as they can be applied to life.

78.88% people think people should be involved in the supervision and management of biotechnology. 21.12% people disagree; they hold that people are so lack of relevant biological knowledge that they cannot have a comprehensive understanding of science.

If you have the opportunity to learn synthetic biology-related courses and take part in IGEM, would you like to have a try? 57.14% people answered yes, they expressed an willingness to have a try, but do not attempt to spend too much time or energy. However, 24.84% people are very glad to join IGEM. There are also 18.01% people that are not very interested in it. If people have taken part in an IGEM team, 36.02% of them want to study the environment and energy direction. 50.31% people are interested in medical and pharmaceutical direction. 9.94% people suggest to study agriculture, and green manufacturing direction. Whereas, 3.73% people prefer to study other directions.

If you can assemble the gene sequences of different modules to customize an e. coli with special features are various, what functions do you want to realize most? The answers are various, to treat diseases, prevent cancer, lose weight, generate electricity, etc.

What is the most urgent problem that synthetic biology should solve? We designed four answers: treatment and prevention of human diseases, command of environment pollution, efficient energy production, construction of appropriate ethical system. The results are as follows:

It is obvious that the great majority people support “treatment and prevention of human diseases” as the most urgent problem. “command of environment pollution” are in the second place, followed by “efficient energy production”. “Construction of appropriate ethical system” was the least.

From this questionnaire, we can easily draw the conclusion that synthetic biology has been developed to some extent in universities in contemporary China, but not very well. The great majority of people do not know synthetic biology or IGEM at all, according to our data. To our relief, most people already have some comprehension to synthetic biology. Although faced with safety issues, many people showed a supportive attitude to the development of synthetic biology. A large percent of people hold the belief that they should possess the power to monitor it. Frankly speaking, there’s a long way to go before realizing people’s demand. There being a vast part of people have the desire to join IGEM, we hope that synthetic biology could be understood by more people, we hope people with such dreams could be able to achieve their goals one day, we hope those worries that people have about synthetic biology could be solved earlier, we hope that more robust management system could be established as soon as possible. As great fans of synthetic biology, as students with great dreams of Tianjin University, we will spread knowledge of synthetic biology heart and soul. We believe synthetic biology will have a better future tomorrow!

③Interaction Activities

(1) Visit to TIB,CAS
On July 31, 2014, our team visited Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, sharing some perspectives of our project and discussing the direction of further application.

After providing them with our preliminary plan, we consulted professors there on our weakness and difficulties, concentrating on the potential applications of our project. In addition to the detection of the concentration of certain micro-molecules or macro-molecules, we were inspired that we may also measure the expression level of different promoters by using our platforms.

Though we know our team may be faced with a lot of difficulties from our visit, we also enjoyed the special tour. New ideas can be inspired through good communication. It provided us with a great opportunity to know deeper about our projects and synthetic biology.

 

(2) Communication with BIT
On September 18, 2014, our team came to Beijing Institute of Technology (BIT) for a brief discussion on our projects. We each made a presentation and exchanged the ideas on both. Through their illustrating, we were well impressed by general idea and delicate design of their project. Apart from the project, we also consulted Professor Zhang Xunwen from School of Aerospace Engineering on some experimental devices, namely an ammeter with accuracy at a magnitude of 10-12. Though we didn’t get the proper device at last, we gained a lot of helpful suggestions. We did learn a lot!

This meeting helped us come to a better understanding and not only of the limitations of our project itself but also of the innovative thinking for developing an overarching structure for a new biological system.

(3)Cooperation with NKU iGEM 2014

We carried out a work of mutually help collaborating with Nankai University iGEM Team. We planned to help each other in several ways. To begin with, we launched a exchange conference in Oct 13, 2014. Both team made a brief introduction about the project firstly. Through their illustration, we were pleased to know that their project is about the synthesis of rhamnolipid from microbes to assist the oil exploitation. Then our team introduced our project and shared the experiences and difficulties on the experiments. In the following part of “Prospecting”, we exchanged our idea about our project on potential applications and blueprinted our further cooperation.

In addition, due to the lack of experiences and related laboratory reagents, we were not able to do SDS-PAGE to identify our target protein and roughly estimate its concentration. So they helped us do the SDS-PAGE and analyze the results. We were very grateful about that!

④Collaborations

In this busy but unforgettable summer, we have devoted our greatest passion; put all the thoughts in the iGEM competition, so as the companions from other universities, I believe. Luckily, however, we utilized our strengths to aid members of the iGEM community and received considerable kind and helpful instructions from other teams so that we can get through many tough moments or come up with new ideas by these joint efforts.

Collaboration with Beijing Institute of Technology(BIT

BIT iGEM team and our team have collaborated in mutual.

①Firstly, we helped them in the modeling part. In their MIN system, some AHL was added to the medium at first. AHL combines with the product of luxR, and they act in concert to repress the function of promoter R0063. As a result, the MIN system cannot work. However, AHL will be degraded by the proteins expressed by Aii gene. As the population of E.coli grows, the concentration of AHL gradually decreases. When it reaches a threshold value, AHL lose the ability to bind with the product of luxR. Then the depression of MIN will be removed. MinC proteins and MinD proteins can bind with each other to form MinCD division inhibitors. The inhibitors can prevent cell division process. After some time, the number of cells that are still able to make binary fission will decrease. Eventually all the cells lose the ability to multiply themselves.


We use a classical model, density-dependent growth model, for our population of E.coli growing simulation. Also we use some other differential equations to describe the dynamic change of AHL, LuxR proteins and MinC proteins. The total equations are as follows:

 

M

The concentration of total MinC proteins

N

Cell density

R

The concentration of total proteins[LuxR]

A

The number of AHL signal

k

Growth constant

kA

The binding rate between AHL and LuxR proteins

kM

Production rate of MinC.

kR

The production rate of LuxR proteins

d

The death rate related with MinC proteins.

di

The degradation rate of materials.

Then we use these equations to simulate the function of MIN system. The results are shown as figure 1 and figure 2.

 
Figure 1. The dynamic change of cell number and total number of LuxR proteins. After a sharp increase, the cell stopped multiplying themselves. With the growing of E.coli, the total number of LuxR proteins also increases. The initial value of cell number we set is 3000.   Figure 2. The dynamic change of MinC proteins and AHL signal. The AHL decrease very quickly with the growth of E.coli. And when AHL comes to the threshold value, the repression of MinC is removed. So after some time the MinC proteins increase quickly and the cell division process is inhibited.

 

②In turn, they have helped us in the measurements of the parts. We send their sample of K1361007, in which CsgA, the major subunit of curli fiber modified by twin 7Xhis tag, is under control of a strong constitutive promoter BBa_J23100. And the K1361007 was arrived in company with a parallel part where BBa_J23104, a relatively weaker promoter, replaced the BBa_J23100. In order to find the better fit of promoter, they helped us measure the cell growth curve of each part and Bradford protein assay was adopted to monitor the total quantity of secrete protein in matrix.

The results are as follows:

 

Screen Shot 2014-10-16 at 4
Figure 3.Cell growth curve of BBa_J23100 and parallel that a relatively weaker promoter was used to control the CsgA secrete level

 

Screen Shot 2014-10-16 at 4
Figure 4. Absorbency of secrete protein in culture between K1361007 and parallel. No significant divergence was found.

 

Collaboration with Nankai University(NKU)

We hosted the 1st  iGEM Exchange Conference Of TJU Team and NKU Team on Oct. 14th at the Nankai University.

The conference contains three parts: The introduction of Work Project, Prospect and Mutual Aid.


First of all, mediators of both teams introduced their project. Nankai University Team introduced their project called Super Petroleum Magician which is an anaerobic rhamnolipid-producing engineered bacterial strain for microbial enhanced oil recovery.


And Tianjin University Team gave a speech about their program named Transfibre which is also called CsgA, a kind of special fiber that can bind the electric circuit and play the role as the conductor as its function.
In the experiment part, they helped us to detect our target protein (CsgA) using SDS-PAGE. Here is the result.

From the result, we could see that the interest protein from cells was about 15 Kp which was same as what we expected, from which we could infer that interest protein unsurely existed.


Tianjin University,Tianjin, China
Email:michaelss@tju.edu.cn