Single-cell approach to monitor the unfolded protein response during biotechnological processes with pichia pastoris ...

• Main Authors: Raschmanová, Hana, Zamora, Iwo, Borčinová, Martina, Meier, Patrick, Weninger, Astrid, Mächler, Dominik, Glieder, Anton, Melzoch, Karel, Knejzlík, Zdeněk, Kovar, Karin
• Format: Text
• Language: English
• Published: Frontiers Research Foundation 2019
• Subjects: Pichia pastoris; Fed-batch culture; Flow cytometry; Heterogeneity; Single-cell; Stress response; Super folder green fluorescent protein sfGFP; Unfolded protein response UPR; 660.6 Biotechnologie; Antarc*; Antarctica
• Online Access: https://dx.doi.org/10.21256/zhaw-19480; https://digitalcollection.zhaw.ch/handle/11475/19480

Pichia pastoris (Komagataella sp.) is broadly used for the production of secreted recombinant proteins. Due to the high rate of protein production, incorrectly folded proteins may accumulate in the endoplasmic reticulum (ER). To restore their proper folding, the cell triggers the unfolded protein response (UPR); however, if the proteins cannot be repaired, they are degraded, which impairs process productivity. Moreover, a non-producing/non-secreting subpopulation of cells might occur, which also decreases overall productivity. Therefore, an in depth understanding of intracellular protein fluxes and population heterogeneity is needed to improve productivity. Under industrially relevant cultivation conditions in bioreactors, we cultured P. pastoris strains producing three different recombinant proteins: penicillin G acylase from Escherichia coli (EcPGA), lipase B from Candida antarctica (CaLB) and xylanase A from Thermomyces lanuginosus (TlXynA). Extracellular and intracellular product concentrations were ...