Difference between revisions of "Part:BBa K3190601"

Revision as of 18:04, 16 October 2019

pGAL1-BI-I: BI-I CDS under inducible promoter

The coding sequence of BAX Inhibitor-I (BI-1) anti-toxin under the control of inducible promoter GAL1 (Basic part BBa_K3190050) for the design of a kill switch system for a yeast wherein a BAX toxin is expressed under a constitutive promoter. This system ensures that the yeast will not survive if it escapes the medium containing the inducer.

Usage and Biology

Improvement of kill switch system

We seek to improve the BI-1 coding sequence (BBa_K2365518), which was submitted by the iGEM team NAU_CHINA 2017. They used it as part of their kill switch system and also submitted a composite part consisting of TEF1 constitutive promoter, the BI-1 coding sequence, and the yeast CYC1 terminator.

The kill switch proposed by team NAU China works by co-expressing the BAX gene (No part name specified with partinfo tag.), which encodes the pro-apoptotic Bax protein, under a constitutive promoter, and BI-1 under the inducible GAL1 promoter. As long as galactose is present in the media, BI-1 will be expressed, inhibiting the Bax protein. Should the yeast cell escape the media or matrix, BAX will be expressed, causing apoptosis of the cell.

Figure 1: Overview of the kill switch.

Our improvement lays in the addition of the pGAL1 promoter in front of the BI-1 sequence. This improvement will allow us to control the expression of BI-1, as the GAL1 promoter allows transcription of BI-1 only in the presence of galactose.

this improvement is necessary to use this system as a kill switch and that the composite Biobrick that NAU-china 2017 themselves submitted is not able to allow apoptosis, since they had a TEF1 promoter controlling BI-1 which is not dependent the environmental galactose amount.

Sequence and Features

Assembly Compatibility:

10
COMPATIBLE WITH RFC[10]
12
COMPATIBLE WITH RFC[12]
21
INCOMPATIBLE WITH RFC[21]
Illegal BamHI site found at 954
23
COMPATIBLE WITH RFC[23]
25
INCOMPATIBLE WITH RFC[25]
Illegal AgeI site found at 377
1000
COMPATIBLE WITH RFC[1000]

@@ Line 3: / Line 3: @@
 <partinfo>BBa_K3190601 short</partinfo>
-The coding sequence of BAX Inhibitor-I anti-toxin under the control of inducible promoter for the design of a kill switch system for a yeast wherein a BAX toxin is expressed under a constitutive promoter. This system ensures that the yeast survives only unless it is present in the medium with inducer.
+The coding sequence of BAX Inhibitor-I (BI-1) anti-toxin under the control of inducible promoter GAL1 (Basic part <partinfo>BBa_K3190050</partinfo>) for the design of a kill switch system for a yeast wherein a BAX toxin is expressed under a constitutive promoter. This system ensures that the yeast will not survive if it escapes the medium containing the inducer.
 ===Usage and Biology===
+<b><font size="3">Improvement of kill switch system</font></b>
-The Biobrick XXXX we seek to improve is the BI-1 coding sequence as it was submitted by the iGEM team NAU_CHINA 2017. They used it as part of their kill switch system and even submitted a composite part consisting of TEF1 constitutive promoter, the BI-1 coding sequence, and the yeast CYC1 terminator.
+We seek to improve the BI-1 coding sequence (<partinfo>BBa_K2365518</partinfo>), which was submitted by the iGEM team NAU_CHINA 2017. They used it as part of their kill switch system and also submitted a composite part consisting of TEF1 constitutive promoter, the BI-1 coding sequence, and the yeast CYC1 terminator.
-Our improvement lays in the addition of the pGAL1 promoter in front of the BI-1 sequence. This improvement is necessary to contain the yeast in a defined environment (, in our case the gum matrix). The GAL1 promoter allows transcription of BI-1 only in the presence of galactose. A yeast strain that expresses BI-1 under control of this promoter and Bax constitutively will therefor only able to survive if enough galactose is present. If a yeast cell escapes its defined environment, the supply of this sugar will likely drop, BI-1 expression is interrupted, which will shift the toxin anti-toxin equilibrium in favor of Bax.
+The kill switch proposed by team NAU China works by co-expressing the BAX gene (<partinfo>BBa K2365048</partinfo>), which encodes the pro-apoptotic Bax protein, under a constitutive promoter, and BI-1 under the inducible GAL1 promoter. As long as galactose is present in the media, BI-1 will be expressed, inhibiting the Bax protein. Should the yeast cell escape the media or matrix, BAX will be expressed, causing apoptosis of the cell.
-We claim that this improvement is necessary to use this system as a kill switch and that the composite Biobrick that NAU-china 2017 themselves submitted is not able to allow apoptosis, since  they had a TEF1 promoter controlling BI-1 which is not dependent the environmental galactose amount.
 [[File:UCopenhagen Killswitch.jpeg|600px]]
-<small> Figure legend: Overview of the toxin/anti-toxin biosafety device. </small>
+<small><b>Figure 1:</b> Overview of the kill switch. </small>
+Our improvement lays in the addition of the pGAL1 promoter in front of the BI-1 sequence. This improvement will allow us to control the expression of BI-1, as the GAL1 promoter allows transcription of BI-1 only in the presence of galactose.
+this improvement is necessary to use this system as a kill switch and that the composite Biobrick that NAU-china 2017 themselves submitted is not able to allow apoptosis, since  they had a TEF1 promoter controlling BI-1 which is not dependent the environmental galactose amount.
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