Best New Basic Part
We made up ComE, comD and mazEF. MazEF is a suicide system in Escherichia coli which consists of a stable toxin mazF and labile antitoxin mazE. MazF causes cell death by cleaving mRNA at a specific site. On the other hand, mazE plays a role of antitoxin which can antagonize the toxin mazF. Originated from Streptococcus mutans, ComE and comD, together, is a part of a two components signal transduction system, TCSTS. ComD is a membrane receptor that will bind to CSP. ComD-CSP complex will then phosphorylate comE and comE will activate the downstream gene. This system is easily utilized by simply changing the downstream gene. For example, our project replaced it with GFP for fluorescence detection. Various way of usages is still waiting to be found and applied for comE, comD TCSTS and mazEF. We believe that these parts will help a lot of iGemers in the future.
BBa_K2292000
Histidine kinase of competence regulon, comD
ComD is a part of a two components signal transduction system of the bacteria Streptococcus mutans. It is a kinase and membrane-associated receptor. After comD binded to the quorum sensing molecule CSP, the comD-CSP complex will phosphorylate comE. Then, the phosphorylated comE can turn on the transcription of downstream gene.
BBa_K2292001
Response regulator of competence regulon, comE
ComE is a response regulator of competence regulon. It binds to comD-CSP complex be phosphorylated. The phosphorylated comE will bind onto a comE responsive promoter on downstream gene, turn on the transcription of it.
In our project, we replaced the downstream gene with GFP. Below is a picture showing how this part work in our construction.
BBa_K2292002
Toxin-antitoxin mazEF
MazEF is a suicide system in Escherichia coli which consists of a stable toxin mazF and labile antitoxin mazE. MazF causes cell death by cleaving mRNA at a specific site. On the other hand, mazE plays a role of antitoxin which can antagonize the toxin mazF.
In general, continuous generation of MazE can prevent the situation of cell death by antagonizing mazF. However, once mazE ceased to be produced, it would be degraded by the protease ClpAP. Hence, the remaining toxin mazF will cause the cell death by cleaving mRNA.
Below is how it works!
