lldPRD operon promoter + RBS from E. coli
This is the promoter region for the lldPRD operon (previously named lct) of E. coli. The lldPRD operon encodes a lactate-dehydrogenase, and the lldPRD promoter has been shown to be induced by L-lactate.
The promoter is repressed/activated by the regulatory protein lldR encoded by the operon. In the absence of L-lactate, lldR binds to two operator sites O1 and O2 in the promoter region and inhibits expression. 
The activity of the promoter may be repressed by chloramphenicol and nutrient-rich growth environment. 
Characterization by ETH iGEM 2015
Check the characterization done by ETH Zurich 2015 iGEM team in the experience page.
Sequence and Features
- 10COMPATIBLE WITH RFC
- 12COMPATIBLE WITH RFC
- 21COMPATIBLE WITH RFC
- 23COMPATIBLE WITH RFC
- 25COMPATIBLE WITH RFC
- 1000Illegal BsaI.rc site found at 335
: Dual role of lldR in regulation of the lldPRD operon, involved in L-lactate metabolism in E. coli. Aguilera et al. J. Bacteriol. 2008, 190(8):2997
: Inducible Membrane-bound L-Lactate Dehydrogenase from Escherichia coli - purification and properties. Futai, M. and Kimura, H. Journal of Biological Chemistry. 1977, 252(16):5820-5827.
Improvement by NEU-CHINA-B iGEM 2018
BBa_k2824006:T7-lldPRD operon promoter-GFP>/h2> <h2> Improve the Characterization of BBa_k82000
In the following figure, we compared the expression of lldPRD operon promoter-GFP and T7-lldPRD operon promoter-GFP. The T7 promoter could enhance gene expression when the concentration of lactic acid was less than 1 m mol/L. Considering that the lactate concentration in yogurt is generally no more than 1m mol/L, the conclusion can given that the T7 promoter can enhance the signal intensity for our experiments (Figure 1). <p> Figure 1:lldPRD operon promoter-GFP vs T7-lldPRD operon promoter-GFP
To see more details about the construction and result, click the hyperlink below: T7-lldPRD operon promoter-GFP composite:BBa_k2824006(http://parts.igem.org/Part:BBa_K2824006).
BBa_k2824008:Lldr-T7-lldPRD operon promoter-GFP
Improve the Characterization of BBa_k82000
<p> We can easily find that the Lldr-T7-lldPRD operon promoter-GFP part are in a higher level of expression comparing to the lldPRD operon promoter-GFP when the lactate concentration is lower than nearly 1.5 mM. Considering that the lactate concentration in yogurt is generally no more than 1 mM, the conclusion can give that the T7 promoter can enhance the signal intensity for our experiments (Figure 2).
Figure 1:Lldr-T7-lldPRD operon promoter-GFP
Figure 2:lldPRD operon promoter-GFP vs Lldr-T7-lldPRD operon promoter-GFP
To see more details about the construction and result, click the hyperlink below:Lldr-T7-lldPRD operon promoter-GFP composite: BBa_k2824008(http://parts.igem.org/Part:BBa_K2824008)