Evaluation of the effects and interactions of mixing and oxygen transfer on the production of Fab' antibody fragments in Escherichia coli fermentation with gas blending.
Fermentations carried out at 450-L and 20-L scale to produce Fab' antibody fragments indicated a serious problem to control levels of dissolved oxygen in the broth due to the large oxygen demand at high cell densities. Dissolved oxygen tension (DOT) dropped to zero during the induction phase and it was hypothesised that this could limit product formation due to inadequate oxygen supply. A gas blending system at 20-L scale was employed to address this problem and a factorial 2(2) experimental design was executed to evaluate independently the effects and interaction of two main engineering factors: agitation rate and DOT level (both related to mixing and oxygen transfer in the broth) on Fab' yields. By comparison to the non-gas blending system, results in the gas blending system at same scale showed an increase in the production of Fab' by 77% independent of the DOT level when using an agitation rate of 500 rpm level and by 50% at an agitation rate of 1,000 rpm with 30% DOT. Product localisation in the cell periplasm of >90% was obtained in all fermentations. Results obtained encourage further studies at 450-L scale initially, to evaluate the potential of gas blending for the industrial production of Fab' antibody fragments.
García-Arrazola
Roeb
R
The Advanced Centre for Biochemical Engineering, Department of Biochemical Engineering, University College London, Torrington Place, London, WC1E 7JE, UK.
Dawson
Pierre
P
The Advanced Centre for Biochemical Engineering, Department of Biochemical Engineering, University College London, Torrington Place, London, WC1E 7JE, UK.
Buchanan
Ian
I
The Advanced Centre for Biochemical Engineering, Department of Biochemical Engineering, University College London, Torrington Place, London, WC1E 7JE, UK.
Doyle
Billy
B
The Advanced Centre for Biochemical Engineering, Department of Biochemical Engineering, University College London, Torrington Place, London, WC1E 7JE, UK.
Fearn
Tom
T
Department of Statistical Science, University College London, Gower Street, London, WC1E 6BT, UK.
Titchener-Hooker
Nigel
N
The Advanced Centre for Biochemical Engineering, Department of Biochemical Engineering, University College London, Torrington Place, London, WC1E 7JE, UK.
Baganz
Frank
F
The Advanced Centre for Biochemical Engineering, Department of Biochemical Engineering, University College London, Torrington Place, London, WC1E 7JE, UK. f.baganz@ucl.ac.uk.
D000911:Antibodies, Monoclonal / Q000096:biosynthesis / Q000235:genetics; D001693:Biological Transport, Active / Q000502:physiology; D019149:Bioreactors / Q000382:microbiology*; D049109:Cell Proliferation; D003198:Computer Simulation; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism*; D005740:Gases / Q000378:metabolism; D006801:Humans; D007140:Immunoglobulin Fab Fragments / Q000096:biosynthesis* / Q000235:genetics; D044085:Microfluidics / Q000379:methods*; D008954:Models, Biological; D010100:Oxygen / Q000378:metabolism*; D010101:Oxygen Consumption / Q000502:physiology*; D015202:Protein Engineering / Q000379:methods*; D011994:Recombinant Proteins / Q000096:biosynthesis
D000911:Antibodies, Monoclonal; D005740:Gases; D007140:Immunoglobulin Fab Fragments; D011994:Recombinant Proteins; D010100:Oxygen