Composite

Part:BBa_K3739087

Designed by: Shichen Geng   Group: iGEM21_XMU-China   (2021-10-20)


K525998(T7-RBS)-his-hutH-FT

Histidine ammonia-lyase with a his-tag is involved in catalyzing the reaction of changing L-histidine into trans-urocanate. The proteins labeled of tetracysteine motif tag (FlAsH tag, FT in short) can be detected with the biarsenical compound FlAsH.

Biology

FlAsH system was previously reported as a fluorescence detector for secreted proteins1. The protein labeled of tetracysteine motif tag (FlAsH tag, FT in short) can react with biarsenical compound FlAsH, showing great fluorescence at 528 nm emission. FlAsH system is used to quantify and qualify the secretion efficiency. We used his-hutH-FT to verify the secretion effect.

Usage

We ligased the induced promoter+RBS (BBa_K525998) and the parts (BBa_K3739086) on the expression vector pSB1C3 by standard assembly (BBa_K3739087). Then the ligation mixture was transformed into E.coli BL21 (DE3), and the correct recombinant one was confirmed by chloramphenicol, colony PCR and sequencing.

Characterization

1.Agarose Gel Electrophoresis
After BBa_K3739087 was constructed on vector pSB1C3 and transformed into E. coli BL21 (DE3), colony PCR was done to verify that the plasmid was correct. Data is shown below:
T--XMU-China--86-1.png
Fig. 1. Colony PCR results of BBa_K3739087
2. Qualification of LMT secretion efficiency
After cultivation for 5 hours at 37℃ and induction for 2 hours with 0.1mM IPTG, the cell supernatant was separated by centrifugation. The supernatant along with 2 μM FlAsH-EDT2 and 1 mM DTT were added to wells in a 96-well plate. Following incubation in the dark for 1 h at 37 °C, fluorescence was measured by 503 nm excitation and 528 nm emission, and each value was normalized by OD600.
T--XMU-China--86-2.png
Fig. 2. Fluorescence intensity/OD600 of cell supernatant after incubation in the dark for 1h.

The result shows that the fluorescence intensity/OD600 of the group Aly01 and LMT is significantly higher than native control group, which proves that these 2 signal peptides can function well.

Reference

1. Haitjema, C. H.; Boock, J. T.; Natarajan, A.; Dominguez, M. A.; Gardner, J. G.; Keating, D. H.; Withers, S. T.; DeLisa, M. P., Universal Genetic Assay for Engineering Extracellular Protein Expression. ACS Synthetic Biology 2014, 3 (2), 74-82.

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
    INCOMPATIBLE WITH RFC[25]
    Illegal NgoMIV site found at 200
    Illegal NgoMIV site found at 636
    Illegal NgoMIV site found at 1371
    Illegal NgoMIV site found at 1607
    Illegal AgeI site found at 273
    Illegal AgeI site found at 1100
    Illegal AgeI site found at 1596
  • 1000
    COMPATIBLE WITH RFC[1000]


[edit]
Categories
Parameters
None