Difference between revisions of "Part:BBa K634002"

Latest revision as of 03:38, 29 September 2011

exaDE

The sensor kinase ExaD responds to the presence of ethanol within the cell and phosphorylates ExaE. The phosphorylated ExaE then acts as an activating transcription factor on PexaA. The operon was studied in Pseudomonas aeruginosa, and found to be under transcriptional regulation by the protein AgmR (1). It was also established that by expressing exaDE under a different promoter, the system could proceed in the absence of AgmR (ibid).

This part is a promoterless monocistronic operon, ready to be put under a desired promoter. When expressed in a cell containing part K634008, genes 5' of K634008 can be expressed in the presence of ethanol.

Without additional directed evolution treatment, this system fluoresced sufficiently to be detected by plate reader, but not by eye. In an experiment where exaDE was induced under the ParaBAD promoter by arabinose, the following data was collected:

While this does show an increase in fluorescence proportional to the ethanol concentration, further engineering will be necessary to turn this BioBrick device into an industrially viable tool.

References

(1) Gliese N., Khodaverdi V., Schobert M., and Gorisch H. (2004) AgmR controls transcription of a regulon with several operons essential for ethanol oxidation in Pseudomonas aeruginosa ATCC 17933. Microbiology 150, 1851-1857.

Sequence and Features