Part:BBa_K2244005

LEV1 repressor

short description

LEV1 is a coding gene encodes fusion protein LexA-VVD

long description

This part is a light-switchable repressor component functions in E. coli cells. A blue light sensor VIVID (VVD), which is a small light-oxygen-voltage (LOV) domain-containing protein from Neurospora crassa, is fused to the C-terminus of DNA-binding domain of LexA repressor of the Escherichia coli SOS regulon. It’s a common feature for several blue light photoreceptors to contain LOV domains, which are able to bind a molecule of flavin mononucleotide (FMN) or flavin adenine dinucleotide (FAD) as chromophore.

Upon blue light irradiation, a cysteine flavin adduct is formed in the VVD domain, causing conformational changes of the domain and the subsequent dimerization of the fusion protein. The activated protein dimer would then bind its cognate operator sequence and repress the promoter activity. When in dark, the absence of dimer allows the proceeding of target gene expression. The LightOff system has high induction efficiency similar to T7-driven pET expression system, yet much lower leakage. This part works under E. coli SOS promoter and operator sequence.

Sequence and Features

Assembly Compatibility:

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

  Unknown
• 1000
  COMPATIBLE WITH RFC[1000]