Table 2 Concentrations of toxic recombinant protein in process fluids due to expression in A. tumefaciens and N. benthamiana along with the corresponding hazardous process volumes
Process step (–) | Bacteria OD600nm (–) | Cbacteria (g DM L−1)b | Ctoxin from bacteria (µg L−1)b,c | Ctoxin from plant (µg L−1)b,c | Ctotal toxin [µg L−1]c | Vcritical (L) depending on LD50 of… | |||
|---|---|---|---|---|---|---|---|---|---|
500 µg kg−1 | 1 µg kg−1 | 1 ng kg−1 | Vprocess (L) | ||||||
Cloning (E. coli) | 2.00 | 0.79 | 62.13 | 0 | 62.13 | 650 | 1.30 | 0.001 | 0.002 |
Pre-culture (A. tumefaciens) | 5.00 | 2.05 | 8.07 | 0 | 8.07 | 5.00 × 103 | 10.00 | 0.01 | 0.05 |
Fermentation | 10.00 | 4.09 | 16.14 | 0 | 16.14 | 2.50 × 103 | 5.00 | 0.005 | 75 |
Infiltrated leavesd | 0.50 | 0.21 | 0.81 | 0 | 0.81 | 50.00 × 103 | 100.00 | 0.10 | 1500 |
Extractiona | 28.20 × 10−3/0 | 11.5 × 10−3/0 | 0.45 × 10−6/0 | 10.10 × 103 | 10.13 × 103 | 3.98 | 7.97 × 10−3 | 7.97 × 10−6 | 800 |
Bag filtrationa | 12.30 × 10−3/0 | 0.50 × 10−6/0 | 0.19 × 10−6/0 | 9.62 × 103 | 9.62 × 103 | 4.19 | 8.39 × 10−3 | 8.39 × 10−6 | 640 |
Depth filtrationa | 1.86 × 10−6/0 | 76.1 × 10−6/0 | 3.00 × 10−6/0 | 8.66 × 103 | 8.66 × 103 | 4.66 | 9.32 × 10−3 | 9.32 × 10−6 | 640 |
Sterile filtration | 0 | 0 | 0 | 8.66 × 103 | 8.66 × 103 | 4.66 | 9,32 × 10−3 | 9.32 × 10−6 | 640 |
UF/DFe | 0 | 0 | 0 | 0.17 × 106 | 0.17 × 106 | 0.23 | 46.6 × 10−3 | 0.47 × 10−6 | 32 |