Figure 2.

Sustained productivity of the methanol‐free strain in perfusion fermentation. (a) Reduced SDS‐PAGE of upstream reactor samples for the duration of each campaign. (b) Upstream reactor titer of RBD. (c) Host cell protein concentrations in purified pools of RBD, measured by ELISA. Error bars represent the standard deviation of three technical replicates. ELISA, enzyme‐linked immunoassay; PPM, parts per million; RBD, receptor‐binding domain; SDS‐PAGE, sodium dodecyl sulphate–polyacrylamide gel electrophoresis