Difference between revisions of "Part:BBa K3962342"

Latest revision as of 07:51, 16 October 2021

arabinose-mediated inducible expression of toxin CcdB

This construct is composed of L-arabinose mediated inducible promoter pBAD and toxin CcdB. CcdB/CcdA is a type II toxin-antitoxin system originating from E. coli. In our project, we used this construct to test the toxicity of toxin CcdB, which provided us with more insights in regulating the balance of the toxin-antitoxin system for preventing horizontal gene transfer.

2021 Team Leiden

https://2021.igem.org/Team:Leiden

CcdB has also been used as a part of a kill switch (Fig. 1) to test the toxicity of the toxin based on arabinose concentration.

Figure 1. Plate reader assay of E. coli TOP 10 cellular growth over time with a gradient of arabinose concentrations.

Cell growth is strongly inhibited following the induction of CcdB. The results show that CcdB is not necessarily enough to kill all cells immediately when grown in liquid LB medium. Only after the exponential growth phase, the cells start to die. High concentrations of arabinose are needed for this killing effect, but that might change in different medium conditions.

Sequence and Features

Assembly Compatibility:

10
COMPATIBLE WITH RFC[10]
12
INCOMPATIBLE WITH RFC[12]
Illegal NheI site found at 1205
21
INCOMPATIBLE WITH RFC[21]
Illegal BamHI site found at 1144
Illegal BamHI site found at 1902
23
COMPATIBLE WITH RFC[23]
25
INCOMPATIBLE WITH RFC[25]
Illegal AgeI site found at 979
1000
INCOMPATIBLE WITH RFC[1000]
Illegal BsaI.rc site found at 1352
Illegal SapI site found at 961

@@ Line 14: / Line 14: @@
 https://2021.igem.org/Team:Leiden
- CcdB has also been used as a part of a kill switch (Fig. 1) to test the toxicity of the toxin based on arabinose concentration.
+CcdB has also been used as a part of a kill switch (Fig. 1) to test the toxicity of the toxin based on arabinose concentration.
 [[Image:T-Leiden-parts-Figuer4.png|500px]]