Fig. 2

rRBD-producing stable clone generation and batch screen. (A) Schematic of the stable expression plasmid. The Geneticin (G418) resistance gene driven by the minimal herpes simplex virus thymidine kinase promoter (MiniTK) is purple, the rRBD gene driven by the CAG promoter is teal, the insulating matrix attachment region (MAR) elements are brown, and the ampicillin resistance gene (AmpR) and origin of replication for Escherichia coli (E. coli ori) are grey. (B) rRBD BLI titer values were normalized relative to the selected pool. Bars for clones with normalized titer > 1 that were chosen for fed-batch process development and scale-up are red, and bars for the pool or clones with normalized titer < 1 are grey. Error bars show SEM for technical replicates of singlet cultures. The corresponding absolute titer used for normalization is shown in Table S2