The science of recombinant protein expression
flashBAC System compared to other leading systems
flashBAC System
- Co-transfect flashBAC & transfer vector into Sf9 cells
- 2 ml P1 stock 1x107-5x107pfu/ml
- 500 ml P2 stock > 1x108pfu/ml
Bac-to-Bac System
- Transform DNA into EH10Bac E.coli = transposition into bacmid
- Blue-white selection of recombinant E.coli on antibiotic plates
- Verify recombinant colonies by PCR
- Amplify and purify DNA. Transfect µl into 35mm2 dish of Sf9 cells
- 2ml P1 stock. 2x107 - 4x107 pfu/ml
- 500 ml P2 stock > 1x108pfu/ml
Baculodirect
- Gene of interest cloned into Gateway entry vector
- Obtain seed stock
- Complete plaque assay of seed stock prior to amplification
to determine titre (optional)
- Obtain high titre virus stock (day 10 if plaque assay not done)
BacPac
- Co transfect BacPak and transfer vector into cells
- Seed stock obtained (2ml)
- Plaque purification completed - 8 days
- Verify recombinant plaques by PCR. Infect flask for P1 stock
- Obtain P1 stock
- Obtain P2 stock (500ml)
BacVector 3000 System
- Co-transfect BacVector 3000 & transfer vector into Sf9 cells
- 2ml P0 stock. 1x106 - 1x107 pfu/ml
- 2 rounds plaque purification = 7 days
- Verify recombinant plaques by PCR. Infect 25 cm2 flask for P1 stock
- 5ml P1 stock. 1x106 - 1x107 pfu/ml
- 500 ml P2 stock > 1x108fu/ml
Bac-n-Blue System
- Co-transfect Bac-n-Blue & transfer vector into Sf9 cells
- 2 ml P1 stock 1x106-1x107pfu/ml
- 2 rounds plaque purification = 7 days
- Verify recombinant plaques by PCR.
Infect 25 cm2 flask for P1 stock
- Amplify 5ml P1 stock 1x106-1x107pfu/ml
- 500 ml P2 stock > 1x108pfu/ml
Note: Timescales are taken from manufacturers user manuals
| Features |
flashBAC System |
Bac-to-Bac System |
Baculodirect |
BacPac |
BacVector 3000 System |
Bac-n-Blue System |
| Bacmid |
Yes |
Yes |
Yes |
Yes |
|
|
| Contains gene deletions to enhance secretion and improve protein yields |
Yes |
|
|
|
Yes |
|
| Utilises homologous recombination in insect cells so recombinant viruses are stable |
Yes |
|
Yes |
Yes |
Yes |
Yes |
| Compatible with standard transfer vectors |
Yes |
|
Yes |
Yes |
Yes |
|
| Doesn’t require plaque purification |
Yes |
Yes |
Yes |
|
|
|