Part:BBa_K1369001

Repressor-Repressor promoter (LacI and TetR operator sites)

This is a repressor-repressor (RR) combinatorial promoter which consists of a LacI operator site upstream of the -35 RNA polymerase binding site, and a TetR operator site within the -35 and -10 RNA polymerase boxes. This RR promoter behaves as an asymmetric-AND gate, such that promoter activity is greatest when both aTc and IPTG inducers are present, but there is some leaky promoter activity when aTc is present, but not IPTG.

In order to test the expression logic of this promoter, we designed test constructs with super-folder GFP, regulated by this RR promoter and a bicistronic RBS (BBa_J119024). A bicistronic RBS (BCD) was instead of a standard RBS because it has been shown that BCDs have more robust gene translation with respect to the downstream sequence.

Heatmap of mean GFP fluorescence (au) as regulated by this RR promoter in vivo. Cells were grown for around 8 hours with various inducer concentrations before measurements were taken.

Barchart of mean GFP fluorescence (au) as regulated by this RR promoter in vivo. This barchart was obtained using the same data that generated the above heatmap.

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
  COMPATIBLE WITH RFC[25]
• 1000
  COMPATIBLE WITH RFC[1000]