Fig 1.

Schematic presentation of the construction of the recombinants with different propeptides. (A) Map of the integrated vector pPIC9k and the cleavage process of the α-factor signal peptide in Pichia pastoris. (B) Structure of the recombinants with different propeptides. YVEF was the residual sequence at the N terminus because of digestion by endonucleases SnaBI and EcoRI and cleavage of the α-factor signal peptide by peptidases KEX2 and STE13. (C) Structure of recombinant trypsin by fusing different designed propeptides.