Part:BBa_K2507017

J23109-ttrR-PttrB185-BBa_K274003

Usage and Biology

E. coli-codon-optimized TtrS(BBa_K2507002) and TtrR (BBa_K2507003) are two basic parts which are derived from the two-component system of the marine bacterium Shewanella baltica. TtrS is the membrane-bound sensor kinase (SK) which can sense tetrathionate outside the cell, and TtrR is the DNA-binding response regulator (RR). PttrB185-269 (BBa_K2507019) is a minimal TtrR-activated promoter which is activated when TtrR is phosphorylated by TtrS after TtrS senses tetrathionate.

Winter et al. have shown that reactive oxygen species (ROS) produced by the host during inflammation convert thiosulfate into tetrathionate, which this pathogen consumes to establish a beachhead for infection (Winter et al, 2010). Thus, tetrathionate may correlate with pro-inflammatory conditions and can therefore be used as a sensor for intestinal inflammation.

Sequence and Features

Assembly Compatibility:

• 10
  COMPATIBLE WITH RFC[10]
• 12
  INCOMPATIBLE WITH RFC[12]

  Illegal NheI site found at 11
  Illegal NheI site found at 34
  
• 21
  COMPATIBLE WITH RFC[21]
• 23
  COMPATIBLE WITH RFC[23]
• 25
  INCOMPATIBLE WITH RFC[25]

  Illegal AgeI site found at 318
  
• 1000
  COMPATIBLE WITH RFC[1000]

Characterization

After validate this system in laboratory Escherichia coli Top10 and E.coli Nissle 1917, this system can function as a tetrathionate sensor and reporter.

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Figure 1. Schematic of ligand-induced signaling through TtrS/R and plasmid design of the sensor components. TtrS/R were tested under the situation BBa_K2507006 was in pSB4K5 backbone and BBa_K2507017 was in pSB1C3 backbone. We submitted the parts all to the iGEM registry in pSB1C3.

Reference

Daeffler, K. N., Galley, J. D., Sheth, R. U., Ortiz‐Velez, L. C., Bibb, C. O., & Shroyer, N. F., et al. (2017). Engineering bacterial thiosulfate and tetrathionate sensors for detecting gut inflammation. Molecular Systems Biology, 13(4), 923.