Part:BBa_K2309030

Switch controller with LacI and TetR

The promoter plac can be repressed by the repressor protein LacI produced by the lacI gene. When lacI reaches a certain concentration, it can stop the promoter plac from transcribing the tetR gene to produce the other repressor protein TetR. Because in Lactococcus lactis, there is originally no natural lacI, the promoter plac is on and is always synthesizing TetR protein to repress the promoter ptet. Therefore, when there is no LacI, TetR can be successfully synthesized and represses ptet, and the downstream gene cannot be transcribed. But when the lacI gene in the upstream is transcribed and LacI therefore represses plac, TetR cannot be synthesized anymore, so nothing to repress the ptet results in the downstream gene starting to be transcribed.

Sequence and Features

Assembly Compatibility:

• 10
  COMPATIBLE WITH RFC[10]
• 12
  COMPATIBLE WITH RFC[12]
• 21
  INCOMPATIBLE WITH RFC[21]

  Illegal BglII site found at 1167
  
• 23
  COMPATIBLE WITH RFC[23]
• 25
  COMPATIBLE WITH RFC[25]
• 1000
  COMPATIBLE WITH RFC[1000]