An optimized fermentation process for recombinant human G-CSF production by Pichia pastoris fed-batch culture

The methylotrophic yeast Pichia pastoris is a powerful system for production of recombinant proteins, showing high ability to secrete properly folded proteins. A major plus is the strong AOX1 promoter highly induced by methanol. The optimal culture conditions for attaining high cell density and expression of human Granulocyte-Colony Stimulating Factor (hG-CSF) in the Pichia pastoris were investigated. Cell growth and hG-CSF production were found to be optimal at temperature of 28 °C and pH of 6.0. By using the three stages fermentation, final dry cell weight and expression of recombinant hG-CSF in a fed-batch culture was reached to 90 g/l and 20 mg/l, respectively. Dry cell density and recombinant protein secretion capacity were increased to 100 g/l and 40 mg/l by feeding of peptone as nitrogen source in the methanol induction phase. This study demonstrates that addition of the appropriate amount of an organic nitrogen source to the fed-batch culture is effective to improve expression of recombinant protein in the methylotrophic yeast P. pastoris.

کلیدواژه ها:

Pichia pastoris ، hG-CSF ، fed-batch ، glycerol ، methanol