Part:BBa_K3002017
3xHA tag for Chlamydomonas reinhardtii (Phytobrick)
This basic part contains the sequence of the HA-tag (B5) and was built as a part of the Kaiser Collection. Combined with a promoter (e.g. BBa_K3002001 (PSAD promoter (A1-B1)) or BBa_K3002031 (PAR promoter (A1-B1))) and terminator (e.g. BBa_K3002006 (RPL23 terminator)) your target protein is secreted efficiently and can be detected via HA-antibody.
All results shown a good detection via HA-tag by doing Western blot analysis. Constructs containing HA-tag can be used for the detection of proteins via HA anti-body. As shown in the results the HA-tag is always a reliable tag for detection.
Overview of different level 2 MoClo constructs. We designed 35 different level 2 constructs by using the modular cloning system (MoClo) and transformed these into Chlamydomonas reinhardtii. These constructs contain promoters (PPSAD, PAR, PTub2), terminators (PSADter, RPL23ter, Tub2ter), and the coding sequences for selection markers (aadA, Hygro), tags (HA, His, SP20-HA, SP20-His), secretion signals (cCA, ARS, GLE) and the enzymes MHETase, wild-type PETase (WT-PETase), mutated PETase (Mut-PETase) and the mutated PETase from the iGEM team TJUSLS China 2016 (Mutate M).
Expression of the enzymes MUT-PETase and MHETase in Chlamydomonas reinhardtii. (a) Level 2 MoClo construct harboring the aadA selection marker and the coding sequences for MUT-PETase, and MHETase (BBa_K3002209, BBa_K3002207, BBa_K3002208) (see Figure 1 for part description). (b) The UVM4 strain was transformed with the construct shown in (a). 11 spectinomycin-resistant transformants were inoculated in TAP and samples taken after 3 days. Extracted whole-cell proteins were analysed by SDS-PAGE and immunoblotting using an anti-HA antibody. MW – molecular weight. The black arrow represents the MHETase, the white arrow the MUT-PETase. The expression of both MHETase (~70 kDa) and MUT-PETase (~35 kDa) is visible in colonies 18, 22 and 27. The UVM4 recipient strain and a strain expressing the HA-tagged ribosomal chloroplastic 50S protein L5 (RPL5) served as negative and positive controls, respectively.
MUT-PETase destined for secretion gets stuck inside the cell. (a) Level 2 MoClo construct harboring the aadA selection marker, and the coding sequences for MUT-PETase and MHETase genes. MUT-PETase and MHETase are equipped with the secretion signal from carbonic anhydrase (cCA). See Figure 1 for the description of other parts. (b) Seven days old cultures of transformants generated with the construct shown in (a) were centrifuged and proteins in the culture medium were precipitated by TCA and analysed by immunoblotting using an anti-HA antibody. The black arrow represents MHETase. (c) Whole-cell proteins of UVM4 cells transformed with construct L2C (BBa_K3002202) shown in (a) were analyzed by immuno-blotting using an anti-HA antibody. Transformant A27 generated with construct L2A (BBa_K3002200) (Figure 4a) and UVM4 were used as positive and negative controls, respectively. The white arrow indicates MUT-PETase. (d) Immunfluorescence analysis of transformants 17 and 27 using an anti-HA antibody. DAPI staining was also performed. UVM4 cells served as control.
Analysis of the secretion of MUT-PETase with secretion signals cCA, GLE, and ARS. (a) Level 2 MoClo constructs harboring the aadA selection marker, and the coding sequences for MUT-PETase equipped with secretion signals from carbonic anhydrase (cCA), gamete lytic enzyme (GLE) and arylsulfatase (ARS). See Figure 1 for the description of other parts. (b) UVM4 transformants containing the constructs shown in (a) were grown in TAP medium for seven days. Cells were centrifuged and the supernatant lyophilized, resuspended in 2xSDS buffer and analyzed by SDS-PAGE and immunoblotting with an anti-HA antibody.Transformants C12 and A27 introduced in Figures 4 and 5, respectively, served as positive controls. The white arrow points to the MUT-PETase.
The SP20 module increases the efficiency of protein secretion. (a) Level 2 MoClo constructs harboring the aadA selection marker, and the coding sequences for MUT-PETase and MHETase equipped with the secretion signals introduced in Figure 6. The constructs contain the coding sequence for a conventional 3xHA tag (C, K, L)(BBa_K3002202, BBa_K3002210, BBa_K3002211), or the 3xHA tag preceded by a SP20 tag to enhance glycosylation (M, N, O). See Figure 1 for the description of other parts. (b) UVM4 transformants containing the constructs C, K, L and M, N, O (BBa_K3002202, BBa_K3002210, BBa_K3002211, BBa_K3002212, BBa_K3002213, BBa_K3002214) were grown in TAP medium for seven days. Cells were centrifuged and the supernatant lyophilized, resuspended in 2xSDS buffer and analyzed by SDS-PAGE and immunoblotting with an anti-HA antibody. Transformant A27 introduced in Figures 4, served as positive control. The black arrow points to MHETase, the white arrow to MUT-PETase and the grey arrow to RPL1 (chloroplast ribosomal 50S protein L1). The RPL1 antibody was used to detect contamination from intracellular proteins.
Quantification of secreted MHETase and MUT-PETase. (a) Transformants generated with constructs C, J, M, N, and O (BBa_K3002202, BBa_K3002208, BBa_K3002212, BBa_K3002213, BBa_K3002214)(Figure 8) were grown in TAP medium for seven days. Cells were centrifuged and the supernatant lyophilized, resuspended in 2xSDS buffer and analyzed by SDS-PAGE and immunoblotting with an anti-HA antibody. Whole-cell extracts of strain B1-TIG-HA for which concentrations of the HA-tagged TIG protein are known are loaded next to the lyophilized supernatants. The black arrow points to MHETase, the white arrows to MUT-PETase. The supernatant of a culture with the UVM4 strain were loaded as negative control. (b) Maximum cell densities, doubling times, daily growth rates, yields of MHETase and PETase and daily productivity of both combined were calculated for the transformant lines indicated.
Purification of HA-tagged MUT-PETase and MHETase from Chlamydomonas and activity measurement against BHET by reversed-phase HPLC. (a) Affinity purification of MUT-PETase and MHETase from Chlamydomonas by anti-HA magnetic beads. Transformants M5 (BBa_K3002212), C12 (BBa_K3002202) and untransformed UVM4 were inoculated in TAP for seven days. Cultures were centrifuged and supernatants incubated with anti-HA magnetic beads for 1 h. Enzymes were purified via biomagnetic separation. Samples of the unconcentrated supernatant (S), of the washing step (W), of the eluted proteins (E) and after 96 h incubation with BHET (A.I.) were analyzed by immunoblotting using an anti-HA antibody. (b) Proteins eluted from Chlamydomonas transformant M5 (producing MUT-PETase and MHETase) and the UVM4 strain (not producing MUT-PETase and MHETase) were incubated with 1 mM BHET in sodium phosphate (NaPi) buffer at 30°C for 96 h. The standard containing 1 mM TPA, MHET and BHET dissolved in DMSO is shown on top.
The Kaiser Collection
We are proud to present our very own MoClo part collection for C. reinhardtii - the Kaiser collection.
These 20 Parts are specifically designed and codon optimized for Chlamydomonas. Among them are regulatory elements, antibiotic resistances, resistance cassettes, secretion signals and tags. These parts were tested and optimized thoroughly and we can guarantee that they work 100%. With these, expression and secretion in Chlamy will be a success. Because this is a MoClo collection, the parts are highly standardized for worldwide application. The combination with other part collections works fast and easy. While in MoClo, nomenclature is a bit different from the iGEM BioBricks, it is quickly explained:
Level 0 parts are equivalent to basic parts, e.g. Promoters, coding sequences, etc.
Level 1 parts are combinations of basic parts and usually form functional transcription units.
Level 2 parts are combinations of Level 1 parts, in case you want to transfer multiple transcription units at once. For example, you can pair your gene of interest with a selection marker.
The great thing about the Kaiser Collection and MoClo is that the ligation works in a one pot, one step reaction, as the Type IIs restriction enzymes cut out their own recognition sites. This way, multiple constructs can be combined linearly in a fixed order to create complex structures. This is ensured by the standardized overlaps that assign the parts one of 10 positions in the final constructs. After trying MoClo once, you won’t go back to traditional ligation. It is incredibly easy and reliable. For this reason, we believe that our Kaiser Collection will strike a significant chord, as the future lies in standardized, easy to use methods such as MoClo. Visit our part collection site to get an overview over all parts of the Kaiser Collection
Sequence and Features
- 10COMPATIBLE WITH RFC[10]
- 12COMPATIBLE WITH RFC[12]
- 21COMPATIBLE WITH RFC[21]
- 23COMPATIBLE WITH RFC[23]
- 25COMPATIBLE WITH RFC[25]
- 1000COMPATIBLE WITH RFC[1000]
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