Fig. 3

YPS1 doesn’t involve in processing the furin cleavage site in Pichia pastoris. a Schematic diagram for constructing a disruption vector with left homology arm and right homology arm of YPS1 gene. b Schematic diagram for knockout of YPS1 gene by homologous recombination. Zeocin can be used for selection of YPS1 knockout strains. Two pairs primers, as shown in figure, were designed to confirm the disrupted strains. c Genomic PCR of YSP1 disrupted and wild type strains using two pairs primers (YI F, YI R and YO F, AOX1 R). A band can be amplified by YI F and YI R primers only if YPS1 gene doesn’t be deleted, and a band can be amplified by YO F and AOX1 primers if YPS1 gene is successfully removed by the disruption construct. d Western blot results of wild type strains. The western blot samples were treated with Endo Hf. e Western blot results of YPS1 disruption strains. The western blot samples were treated with Endo Hf. f Quantitative analysis of the western blot results. NS not statistically significant