Composite Part
fimB(wild-type) controlled arabinose: BBa_K1632012
BBa_K1632012 meet the criteria of the Silver Medal
FimB (BBa_K1632010) is a Fim recombinase. This is derived from the wild type MG1655. FimB invert the fim switch in the ON-to-OFF direction and in the OFF-to-ON direction (Fig.5-3-0-1.).
From our experimental results, we confirmed that the FimB protein inverts the fim switch in the ON-to-OFF direction and in the OFF-to-ON direction with approximately equal probability and works ideally (Fig.5-3-0-2.). The expression of FimB is controlled by arabinose in PBAD/araC_fimB(wild-type) (BBa_K1632012).
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Fig.5-3-0-1. Design of fim switch (wild-type) |
0.Tokyo Tech 2015 iGEM Team: The Others Composite Parts
Name | Type | Description | Design | Length(bp) | Experiment |
BBa_K1632002 | Regulatory | fim switch[default ON](Tokyo_Tech/J23119)_gfp | Riku Shinohara | 1178 | Work |
BBa_K1632003 | Regulatory | fim switch[default OFF](Tokyo_Tech/J23119)_gfp | Riku Shinohara | 1178 | Work |
BBa_K1632007 | Composite | fim switch[default ON](wild-type)_gfp | Riku Shinohara | 1128 | Work |
BBa_K1632008 | Composite | fim switch[default OFF](wild-type)_gfp | Riku Shinohara | 1128 | Work |
BBa_K1632012 | Composite | PBAD/araC_fimB(wild-type) | Riku Shinohara | 1839 | Work |
BBa_K1632013 | Composite | Pbad/araC_fimE(wild-type) | Riku Shinohara | 1835 | Work |
BBa_K1632018 | Composite | J23100_lasR_TT_Plux_fimE (wild-type) | Jun Kawamura | 1609 | |
BBa_K1632019 | Composite | J23100_rhlR_TT_Plux_fimE (wild-type) | Jun Kawamura | 1615 | |
BBa_K1632020 | Composite | rbs_CmRssrA | Jun Kawamura | 712 | Work |
BBa_K1632022 | Composite | J23100_lasR_TT_Plux_CmRssrA | Jun Kawamura | 1704 | Work |
BBa_K1632023 | Composite | J23100_rhlR_TT_Plux_CmRssrA | Jun Kawamura | 1710 | Work |
1. Best New Improved Part: BBa_K1632020, BBa_K1632022, BBa_K1632023
At the first stage of our wet experiment about chloramphenicol resistance(CmR), we used “rbs_CmR” (BBa_K395160 by iGEM 2010 team Tokyo_Tech). However, the result showed a leaky expression of CmR. We inserted an ssrA degradation tag to the C-terminal of CmR. In the our experiment using the Pcon_lasR_TT_Plux_CmRssrA (BBa_K1632022) and Pcon_rhlR_TT_Plux_CmRssrA (BBa_K1632023), we could not observe cell growth for cells that owned the ssrA-tagged plasmid, in the absence of AHL (Fig.5-3-1-1). From our experiment, CmRssrA work better than CmR without ssrA tag for our project.
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Fig.5-3-1-1. The cell’s growth with Cm |
2. fim switch(wild-type) with gfp: BBa_K1632007, BBa_K1632008
We are the first team in iGEM to successfully construct both the fim switch default ON and the fim switch default OFF and experimented them. These fim switch is derived from a wild type and the gene sequence is the same as that of a wild type. The fim switch is inverted by the Fim recombinase. Therefore, we can regulate the expression of the gene downstream of the fim switch by adding the Fim recombinase. From the results of experiment with flow cytometers , they work ideally (Fig.5-3-2-1. and Fig.5-3-2-2) .
3. fim switch(Tokyo_Tech) with gfp: BBa_K1632002, BBa_K1632003
We designed another fim switch(Tokyo_Tech), the promoter of the fim switch(wild-type) is replaced with J23119 promoter(BBa_J23119) and two restriction enzyme cut sites are added in each side of the promoter. Due to this addition of the restriction enzyme cut sites, we were able to replace the J23119 promoter in the fim swtich(Tokyo_Tech). For example, we replaced J23119 promoter (BBa_J23119) with Lac promoter (BBa_R0010). (Fig.5-3-4-1).
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Fig.5-3-3-1. Design of fim switch (Tokyo_Tech) |
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Fig.5-3-3-2. Replace the promoter of fim switch (Tokyo_Tech) |
4. fimE(wild-type) controlled by AHL: BBa_K1632018, BBa_K1632019
FimE is a Fim recombinase. This Fim recombinase is derived from the wild type MG1655. FimE invert the fim switch in the ON-to-OFF direction. The expression of these Fim recombinases are controlled by AHL in Pcon_lasR_TT_Plux_fimE(wild-type) (BBa_K1632018) and Pcon_rhlR_TT_Plux_fimE (BBa_K1632019).