Composite

Part:BBa_K4806200

Designed by: Luca Langenberg   Group: iGEM23_RPTU-Kaiserslautern   (2023-09-18)
Revision as of 16:14, 9 October 2023 by Lulang (Talk | contribs)


CYP3A4 gene with HA-tag for Chlamydomonas reinhardtii (Phytobrick)


This composite part contains the AβSAP(i)-promotor (BBa_K4806013), the coding sequence of CYP3A4 (BBa_K4806000), the HA-tag (BBa_K3002017)* for detection and the tRPL23-terminator (BBa_K3002006)*. This part is codon-optimized for Chlamydomonas reinhardtii and was built as part of the CYPurify Collection. This level 2 part leads to expression and potential detoxification of specific chemicals (Ohkawa & Inui, 2015).


Construct

Fig.1 Construct design
This construct was designed using the modular cloning system (MoClo).

The resistance cassette for spectinomycin is already built in the level 2 vector pMBS807 we are using. The usage of this vector allows the direct assembly of level 0 parts to level 2 constructs, facilitating the cloning time (Niemeyer & Schroda, 2022).


Sequence and Features


Assembly Compatibility:
  • 10
    INCOMPATIBLE WITH RFC[10]
    Illegal PstI site found at 1846
    Illegal PstI site found at 2168
    Illegal PstI site found at 2228
    Illegal PstI site found at 2700
    Illegal PstI site found at 2769
    Illegal PstI site found at 2873
  • 12
    INCOMPATIBLE WITH RFC[12]
    Illegal NheI site found at 249
    Illegal PstI site found at 1846
    Illegal PstI site found at 2168
    Illegal PstI site found at 2228
    Illegal PstI site found at 2700
    Illegal PstI site found at 2769
    Illegal PstI site found at 2873
  • 21
    INCOMPATIBLE WITH RFC[21]
    Illegal XhoI site found at 530
  • 23
    INCOMPATIBLE WITH RFC[23]
    Illegal PstI site found at 1846
    Illegal PstI site found at 2168
    Illegal PstI site found at 2228
    Illegal PstI site found at 2700
    Illegal PstI site found at 2769
    Illegal PstI site found at 2873
  • 25
    INCOMPATIBLE WITH RFC[25]
    Illegal PstI site found at 1846
    Illegal PstI site found at 2168
    Illegal PstI site found at 2228
    Illegal PstI site found at 2700
    Illegal PstI site found at 2769
    Illegal PstI site found at 2873
    Illegal NgoMIV site found at 2090
    Illegal NgoMIV site found at 3592
    Illegal AgeI site found at 268
  • 1000
    COMPATIBLE WITH RFC[1000]


Results

We detected the expression of CYP3A4 with HA-tag via immunoblotting.

Fig.2 Expression of CYP3A4 with HA-tag
(a)Level 2 MoClo construct for expression of the enzyme CYP3A4 containing the HA-tag was designed (see Fig.1 for part description)
(b) Picture of resulting western blot. The enzyme CYP3A4 is marked by a black arrow, the white arrow marks a cross reaction of antibodies. For reference, the UVM4 recipient strain and a strain expressing the HA-tagged ribosomal chloroplast 50S protein L5 (RPL5) were used as a negative and positive control, respectively

For detection the UVM4 strain was transformed with the construct in (a). 30 spectinomycin-resistant transformants were cultivated in TAP medium and samples were taken after 3 days. Whole-cell proteins were extracted and analyzed by SDS-PAGE and immunoblotting using an anti-HA antibody. The expression of CYP3A4 (~ 57 kDa) is visible.


We tried to supertransform the POR with HA-tag (BBa_K4806209) into positive CYP3A4 strains.

Fig.2 Supertrafo of the POR into positive CYP3A4 strains
(a) Level 2 MoClo constructs for expression of the enzymes CYP3A4 and the POR containing the HA-tag. (b) The CYP3A4 strain was transformed with the POR construct in (a). 30 hygromomycin-resistant transformants were cultivated in TAP-medium and samples taken after 3 days. Whole-cell proteins were extracted and analyzed by SDS-PAGE and immunoblotting using an anti-HA antibody. In the resultant the white arrow marks a cross reaction of antibodies. The expression of CYP3A4 (~57 kDa) is visible. The expression of the POR (~ 77 kDa) is not visible. For reference, the UVM4 recipient strain and a strain expressing the HA-tagged ribosomal chloroplastic 50S protein L5 (RPL5) were used as a negative and positive control, respectively.

Sadly we were not able to detect the expression of the POR.


We detected that the construct CYP3A4 with HA-tag (BBa_K4806200) is correctly embedded within the membrane via freeze-thaw assay and immunoblotting.

Fig.3 Freeze thaw assay of CYP3A4 with HA-tag
(a) Level 2 MoClo construct for expression of the enzyme CYP3A4 containing the HA-tag was designed. (b) The UVM4 strain was transformed with the construct in (a). An anti-HA antibody was used to detect the enzyme CYP3A4 (A). For control an anti-Cytf antibody was used to detect the membrane bound proteins and a CGE1-antibody for soluble proteins (B). 30 spectinomycin-resistant transformants were cultivated in TAP-medium and samples taken after. 3 days. For reference whole-cell proteins were extracted and analyzed by SDS-PAGE and immunoblotting. The other samples were treated according to protocol and analyzed also by SDS-PAGE and immunoblotting. The expression of CYP3A4 (~57 kDa) is visible in the pellet (P) and not in the supernatant (S) confirming the membrane intercalation. For reference, the UVM4 strain was used as a negative control.

We were able to detect the expression of CYP3A4 within the pellet, demonstrating that our CYP is correctly embedded within the membrane.


We tried to detect the activity of CYP3A4 with HA-tag (BBa_K4806200) by incubating them in the antibiotic Erythromycin.

Fig.4 Growth test
(a) Level 2 MoClo construct for expression of the enzyme CYP3A4 containing the HA-tag. (b) Positive CYP3A4 transformants

Our initial assumption was that this test yielded a positive result due to the increased slope of the E26 strain and the associated faster grwoth. Unfortunately, this strain also grows faster without erythromycin, which does not provide a conclusive indication of activity. The E2 strain even exhibits greater sensitivity to erythromycin compared to the wildtype UVM4.


8 Survivability Assay xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx


We tried to detect the activity of CYP3A4 with HA-tag (BBa_K4806200) via drop-test.

Fig.5 Drop-test
(a) Level 2 MoClo construct for expression of the enzyme CYP3A4 containing the HA-tag. (b) 10 µl positive CYP3A4 transformants were dropped on TAP-plates as control. (c) 10 µl positive CYP3A4 transformants were dropped on TAP-plates containing 8 mg/l erythromycin. UVM4 strains were used as negative control.

We dropped all our positive CYP3A4 transformants with HA-tag on plates with and without erythromycin. At this erytrhomycin concentration no wildtype should grow, as previously tested. As the incubation time of this test was much longer than the testing, spontaneous mutations occured in the nagtive control. Therefore this experiment does not verify activity of our enzymes.


6 hplc erythromycin xxxxxxxxxxxxxxxxxxxxxxxxxx


7 estradiol geschichte xxxxxxxxxxxxxxxxxxx


8 nanodrop geschichte xxxxxxxxxxxxx


Contribution

The * marked parts were not created by us. Our results can be found on the experience page of each part.

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