Effects of temperature and glycerol and methanol-feeding profiles on the production of recombinant galactose oxidase in Pichia pastoris.
Optimization of protein production from methanol-induced Pichia pastoris cultures is necessary to ensure high productivity rates and high yields of recombinant proteins. We investigated the effects of temperature and different linear or exponential methanol-feeding rates on the production of recombinant Fusarium graminearum galactose oxidase (EC 1.1.3.9) in a P. pastoris Mut(+) strain, under regulation of the AOX1 promoter. We found that low exponential methanol feeding led to 1.5-fold higher volumetric productivity compared to high exponential feeding rates. The duration of glycerol feeding did not affect the subsequent product yield, but longer glycerol feeding led to higher initial biomass concentration, which would reduce the oxygen demand and generate less heat during induction. A linear and a low exponential feeding profile led to productivities in the same range, but the latter was characterized by intense fluctuations in the titers of galactose oxidase and total protein. An exponential feeding profile that has been adapted to the apparent biomass concentration results in more stable cultures, but the concentration of recombinant protein is in the same range as when constant methanol feeding is employed.
Industrial Biotechnology, Dept. of Chemical and Biological Engineering, Chalmers University of Technology, Gothenburg, SE-412 96, Sweden; Wallenberg Wood Science Center, Chalmers University of Technology, Kemigården 4, Gothenburg, SE-412 96, Sweden.
George E
GE
Anasontzis
Margarita
M
Salazar Penã
Oliver
O
Spadiut
Harry
H
Brumer
Lisbeth
L
Olsson
D005285:Fermentation; D005670:Fusarium / Q000201:enzymology; D005692:Galactose Oxidase / Q000096:biosynthesis* / Q000235:genetics; D015966:Gene Expression Regulation, Fungal; D005990:Glycerol / Q000494:pharmacology; D000432:Methanol / Q000494:pharmacology*; D010843:Pichia / Q000235:genetics; D011994:Recombinant Proteins / Q000096:biosynthesis* / Q000235:genetics; D013696:Temperature
D011994:Recombinant Proteins; D005692:Galactose Oxidase; D005990:Glycerol; D000432:Methanol
Fusarium graminearum; Pichia pastoris; galactose oxidase; methanol feeding; optimization