Part:BBa_K769001
PompC-RBS-GFP-Double terminator
When OmpC promotor is activated by phosphorylated OmpR, GFP is expressed.
Usage and Biology
Characterization by team IGEM19_UI_Indonesia
Highest expression of GFP in TOP10 E. coli strain
The plate reader results for the fluorescence intensity of GFP in three bacterial strains TOP10, DH5a and BL21 are obtained from our plate reading. Essentially, all strains of bacteria showed increased fluorescence with increasing NaCl concentrations in LB medium with the highest expression at 2.5 mg/20mL. Interestingly, TOP10 showed sharp increase in fluorescence when cultured with 2.5 mg/20mL NaCl in LB medium compared with 2.0 mg/20mL NaCl in LB medium. DH5a strain showed a
Expression of GDP in TOP10 showed a sharp increase at 2.5 mg/20mL NaCl concentration compared
Expression of GFP in TOP10 showed a sharp increase at 2.5 mg/20mL NaCl concentration compared to 2.0 mg/20mL concentration. This is contradicting our thinking that TOP10 will have a lower expression compared to BL21 because BL21 is a protein expression bacteria. A possible reason for this phenomenon is that there are differences in ompC promoter regulation in different bacterial strains. According to a characterization done by SDU-Denmark, it is found that OmpR-regulated promoter showed a high leaky expression in high copy vectors (e.g. TOP10) compared to low copy vectors (e.g. BL21) confirming our findings in our characterization. From the results, DH5a then BL21 showed a gradual increase in expression with increasing NaCl concentrations in LB medium. This indicates that DH5a and BL21 has a much more efficient control of gene expression with the ompC promoter.
Sequence and Features
- 10COMPATIBLE WITH RFC[10]
- 12COMPATIBLE WITH RFC[12]
- 21INCOMPATIBLE WITH RFC[21]Illegal BamHI site found at 656
Illegal XhoI site found at 557 - 23COMPATIBLE WITH RFC[23]
- 25COMPATIBLE WITH RFC[25]
- 1000COMPATIBLE WITH RFC[1000]
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