| Popis: |
We have used the recombinant baculovirus expression vector system, based on Autographa californica Nuclear Polyhedrosis Virus (AcMNPV) grown in Spodoptera frugiperda (Sf9) insect cells, to produce three proteins: antistasin, half-antistasin, and β-adrenergic receptor. Sf9 cell growth and baculovirus infection processes were developed in gassed spinner flasks and stirred tanks (1–40 liter scale). Both serum-containing and serum-free media were evaluated. Cell growth and product accumulation were found to be adversely affected by too low (below 20% air saturation) or too high (over 100%) a level of dissolved oxygen. The post-infection increases in modal cell diameter and percent cell death were identified as useful indicators of optimum harvest time. In the case of antistasin, productivity was improved by optimizing cell density at infection, multiplicity of infection, dissolved oxygen level and harvest time. In the case of β-adrenergic receptor, protein yield was further enhanced by the addition of protease inhibitors late in the infection cycle. Antistasin, Half-antistasin, β-adrenergic receptor, insect cell culture, recombinant protein, baculovirus, fermentation, large-scale, serum-free, protease inhibitors. |
