Identification and characterization of novel promoters for recombinant protein production in yeast Pichia pastoris

Pichia pastoris expression system has been widely used in recombinant protein production. So far the majority of heterologous proteins are expressed by methanol inducible promoter P-AOX1 and constitutive promoter P-GAP. The use of other promoters is rather limited. Here we selected 16 potentially efficient and regulatory promoter candidates based on the RNA-seq and RNA folding free energy G data. GFP and recombinant amylase were inserted after these promoters to reveal their strength and efficiency under different carbon sources and culture scales. Two novel promoters were successfully identified and could possibly be applied in recombinant protein expression: the methanol-inducible promoter P-0547 and the constitutive promoter P-0472.