Part:BBa_K5210021

pRM-Cl857-pR-MazF

The temperator-sensitive lambda CI repressor protein has a CI⁸⁵⁷ mutation, and when the temperature is reduced to 30℃, CI⁸⁵⁷ converges to synthesize a dimer, binds to the promoter PR and inhibits it, resulting in suppression of downstream toxin mazF expression. Therefore, when the temperature decreased, MazF cannot expressed toxic proteins and do no harm to the engineered bacteria. (MazF belong to the toxin-antitoxin suicide system.)

However, when the temperature increased to 37℃, CI⁸⁵⁷ repressor protein denaturated, CI repressor could no longer bind to promoter PR and play a repressor role, and a large number of downstream toxin MazF was expressed instead. Eventually kill the engineered bacteria in seawater. The skeleton of this genetic route comes from Wang, X., et al.[1]

Usage and Biology

We designed a temperature control system to promote engineered bacterial toxin proteins to trigger bacterial death by controlling the temperature .It can be used as a safety guarantee so that the engineered bacteria can die when heating(37℃). It can solve the problem of handling engineered bacteria leakage in the sea, ensuring that they play a role while doing not damage the environment.

Reference

[1] Wang, X., Han, J. N., Zhang, X., Ma, Y. Y., Lin, Y., Wang, H., Li, D. J., Zheng, T. R., Wu, F. Q., Ye, J. W., & Chen, G. Q. (2021). Reversible thermal regulation for bifunctional dynamic control of gene expression in Escherichia coli. Nature communications, 12(1), 1411. https://doi.org/10.1038/s41467-021-21654-x

Assembly Compatibility:

• 10
  COMPATIBLE WITH RFC[10]
• 12
  COMPATIBLE WITH RFC[12]
• 21
  COMPATIBLE WITH RFC[21]
• 23
  COMPATIBLE WITH RFC[23]
• 25
  COMPATIBLE WITH RFC[25]
• 1000
  COMPATIBLE WITH RFC[1000]