Part:BBa_R0065

Promoter (lambda cI and luxR regulated -- hybrid)

cI repressor negatively regulates this promoter and LuxR activates its transcription.The effect of cI is dominant over LuxR. This part is based on the LuxR and cI repressor regulated hybrid promoter designed and tested by Ron Weiss. It requires the binding of two cI repressor dimers for maximal repression and contains two cI repressor binding sites namely, OR1 and OR2. This promoter is leaky in the sense that 'some' transcription is seen in the absence of both cI and LuxR.

LuxI	cI	activity of promoter
+	+	zero
+	-	maximum
-	+	zero
-	-	leaky (no quantitative information)

Usage and Biology

Pretty good 'off' in the absence of LuxR/HSL. [jb, 5/24/04]

• very leaky (no LuxR/HSL) at high (100-300) copy number. can only be slightly induced by LuxR+3OC6HSL. (jt, ut-austin; 08/11/05)
• Part has since been improved by the [http://2010.igem.org/Team:MIT 2010 MIT iGEM] team in the form of the part Part:BBa_K415032 where the second -10 promoter region has been removed, and the part is thus less leaky.

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]

Functional Parameters: Austin_UTexas

BBa_R0065 parameters

Burden Imposed by this Part:

Burden Value: 1.2 ± 2.8%

Burden is the percent reduction in the growth rate of E. coli cells transformed with a plasmid containing this BioBrick (± values are 95% confidence limits). This BioBrick did not exhibit a burden that was significantly greater than zero (i.e., it appears to have little to no impact on growth). Therefore, users can depend on this part to remain stable for many bacterial cell divisions and in large culture volumes. Refer to any one of the BBa_K3174002 - BBa_K3174007 pages for more information on the methods, an explanation of the sources of burden, and other conclusions from a large-scale measurement project conducted by the 2019 Austin_UTexas team.

This functional parameter was added by the 2020 Austin_UTexas team.