Coding

Part:BBa_K2617017

Designed by: Changyu Li   Group: iGEM18_UESTC-China   (2018-09-30)


J23100-RBS-pelB-5D

A combination system of promoter, ribosome binding site and signal peptide for enhancing protein expression(pelB)

Sequence and Features

Assembly Compatibility:
  • 10
    COMPATIBLE WITH RFC[10]
  • 12
    INCOMPATIBLE WITH RFC[12]
    Illegal NheI site found at 7
    Illegal NheI site found at 30
  • 21
    COMPATIBLE WITH RFC[21]
  • 23
    COMPATIBLE WITH RFC[23]
  • 25
    INCOMPATIBLE WITH RFC[25]
    Illegal NgoMIV site found at 115
  • 1000
    COMPATIBLE WITH RFC[1000]

Characterization

We have improved the previous part BBa_J23100 by adding RBS and pelB-5D to make it can be used for extracelluar expression. The combination of promoter, RBS and signal peptide makes it convenient to use as a Biobrick and gives it the function of extracellular expression.

Link to previous part:http://parts.igem.org/Part:BBa_J23100

For the function determination, we chose the PETase as our reporter protein because its activity can be easily detected. Thus we constructed two plasmids with and without pelB-5D respectively to compare the function of our improved part and previous part.

No. Vector E.coli resistance Vector map Description
1
Positive Control
Kan
T--UESTC-China--RBS+pelB+5D+PETase.png
BBa_J23100-RBS-pelB+5D-PETase-Ter
2
Negative Control
Kan
T--UESTC-China--RBS+PETase.png
BBa_J23100-RBS-PETase-Ter

Experiment Result

For quantitative assay, a standard curve of pNP ranging from 0-0.8 mM in 100 mM of phosphate buffer (pH 7.4) was measured.

Fig. 1The standard curve of pNP.

The activity of the extracelluar fractions was detected by the method of pNPB. And the results were as followed(Fig. 2).

Fig. 2 The activity for extracellular fractions of Positive Control and Negative Control

Based on our functional determination test results, the improvement that we did has succeeded. PETase that carrying our improved part (Fig. 2) has much higher activity level than the PETase that carrying promoter BBa_J23100 but without pelB-5D. From our experiment result, we could conclude that our improved part indeed gives the promoter BBa_J23100 the function of extracellular expression.


[edit]
Categories
//chassis/prokaryote/ecoli
Parameters
None