Fed-Batch Fermentation of GM-CSF-Producing Glycoengineered Pichia pastoris Under Controlled Specific Growth Rate

Abstract

Background: Yeast expression systems with altered N-glycosylation are now available to produce glycoproteins with homogenous, defined N-glycans. However, data on the behaviour of these strains in high cell density cultivation are scarce. Results: Here, we report on cultivations under controlled specific growth rate of a GlycoSwitch-Man5 Pichia pastoris strain producing Granulocyte-Macrophage Colony-Stimulating Factor (GM-CSF) at high levels (hundreds of milligrams per liter). We demonstrate that homogenous Man5GlcNAc2 N-glycosylation of the secreted proteins is achieved at all specific growth rates tested. Conclusions: Together, these data illustrate that the GlycoSwitch-Man5 P. pastoris is a robust production strain for homogenously N-glycosylated proteins.