Engineering complex-type N-glycosylation in Pichia pastoris using GlycoSwitch technology

摘要

Here we provide a protocol for engineering the N-glycosylation pathway of the yeast Pichia pastoris. The general strategy consists ofthe disruption of an endogenous glycosyltransferase gene (OCH1) and the stepwise introduction of heterologous glycosylationenzymes. Each engineering step results in the introduction of one glycosidase or glycosyltransferase activity into the Pichiaendoplasmic reticulum or Golgi complex and consists of a number of stages: transformation with the appropriate GlycoSwitch vector,small-scale cultivation of a number of transformants, sugar analysis and heterologous protein expression analysis. If desired, the resulting clone can be further engineered by repeating the procedure with the next GlycoSwitch vector. Each engineering step takes~3 weeks. The conversion of any wild-type Pichia strain into a strain that modifies its glycoproteins with Gal_2GlcNAc_2Man_3GlcNAc_2 N-glycans requires the introduction of five GlycoSwitch vectors. Three examples of the full engineering procedure are provided toillustrate the results that can be expected.