T7-lldPRD operon promoter-GFP
LLDPRD promoter can sense the presence of lactic acid, in the absence of lactic acid, only a lower background level of expression, but in the presence of lactic acid can open gene expression. We integrated the GFP reporter gene into downstream this promoter to respond to the presence of lactic acid. In order to improve the GFP expression, we integrated a strong promoter, T7, into the upstream of lldPRD region. This part is constructed based on the part lldRO1-plldR-lldRO2 (BBa_k82000) (http://parts.igem.org/Part:BBa_K822000). lldRO1-plldR-lldRO2 part is a lactic acid regulated promoter that is open to gene transcription in the presence of lactic acid. It can effectively improve the expression of the target gene and detect whether the target gene is expressed or not. At the same time, it can accurately determine the amount of the target gene. This allows the overall work of our system to be reflected in digital form.
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).
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: lldPRD operon promoter + RBS from E. coli ( lldRO1-plldR-lldRO2 )：BBa_k82000(http://parts.igem.org/Part:BBa_K822000)
Sequence and Features
- 10COMPATIBLE WITH RFC
- 12COMPATIBLE WITH RFC
- 21COMPATIBLE WITH RFC
- 23COMPATIBLE WITH RFC
- 25COMPATIBLE WITH RFC
- 1000Illegal BsaI.rc site found at 421
Illegal BsaI.rc site found at 1080