Team:TMU-Tokyo/Project/Idea

From 2013.igem.org



Overview



Our project, “GenomEngineer” has two aspects which are “Standardization” and “Implementation”. We tried to establish and standardize a new method to insert Biobrick parts or devices in a genome of E.coli and functionalize them. And we named this method, “Breakthrough” because we believe that this method is new, safe and convenient to all of other iGEMers (→”Standardization”). Then, according to “Breakthrough”, we really inserted the device which we designed in a genome of E.coli and functionalized it (→”Implementation”).



Background and our goal



In iGEM, most teams have inserted their Biobrick parts or devices into plasmids and have used them. It is true that there are many good points to use plasmids, for instance, it is easy to do transformation, and it is convenient to use high copy plasmid when you want to get high amount of gene expression. However, there are some bad points to use plasmids too. For example, when the reproduction starting point of plural plasmids are covered, they are unstable to coexist at the 1 cell (Fig.2.A.). Also the expression of genes which are in plasmids is sometimes leaky (Fig.2.B). Additionally, it isn’t possible to clone the fragment that over 15kb to plasmids (Fig.2.C). We summarized an advantage and a fault of the plasmids in a lower table. (Table1)

In order to solve these problems, we thought that we should create a new method to use Biobricks in a genome of E.coli. In this method, plasmids are only used as templates. We think that using this method is more convenient and safe than using plasmids. There are following reasons that we think about like that. We describe these reasons below.

In order to solve these problems, we thought that we should create a new method of using Biobricks in a genome of E.coli. We think that using this method is more convenient and safe than using plasmids. There are several reasons that we think about like that. For instance,



It’s convenient to use and contributes to the other iGEMers

  • It’s easy to control closely the expression of the genes which are in the genome(Fig.2.D).
  • The size of the gene fragment which is inserted hasn’t a limit (Fig.2.E).
  • The gene once inserted in the genome is hard to deleted. When you insert Biobricks in the genome and use them, this property is a merit. (⇔Plasmids is sometimes lost.) (Fig.2.F)



It contributes to the environment and human beings.

  • The gene once inserted in the genome is hard to spread horizontally, so genes which was modified artificially are hard to spread. (⇔The gene inserted in plasmids is easy to move to other bacteria by the horizontal spread.)


⇒The gene once inserted in the genome is hard to deleted. Therefore, genes which modified artificially are easy to be saved in E.coli. This aspect sometimes will be dangerous. So, in our method, it is required to insert some device like “Kill Switch” to evade danger. If even you could care about it, this method is the great tool which is more useful than a conventional experimental method.


Because of these reasons, we designed and created a new method to insert Biobricks into a genome of E.coli. Also we standardized this method in order to all the other iGEMers could use this (Please check “Breakthrough” page!). page!).