title: Influence of specific growth rate on specific productivity and glycosylation of a recombinant avidin produced by a Pichia pastoris Mut+ strain.
abstract: A recombinant avidin-producing Mut+ Pichia pastoris strain was used as a model organism to study the influence of the methanol feeding strategy on the specific product productivity (q(p)) and protein glycosylation. Fed-batch cultivations performed at various specific growth rates (micro) and residual methanol concentrations showed that the specific avidin productivity is growth-dependent. The specific productivity increases strongly with the specific growth rate for micro ranging from 0 to 0.02 h(-1), and increases only slightly with the specific growth rate above this limit. N-terminal glycosylation was also found to be influenced by the specific growth rate, since 9-mannose glycans were the most abundant form at low growth rates, whereas 10-mannose carbohydrate chains were favored at higher micro. These results show that culture parameters, such as the specific growth rate, may significantly affect the activity of glycoproteins produced in Pichia pastoris. In terms of process optimization, this suggests that a compromise on the specific growth rate may have to be found, in certain cases, to work with an acceptable productivity while avoiding the addition of many mannoses.
authors.affiliation: Laboratory of Chemical and Biochemical Engineering, Ecole Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland.
authors.forename: Jonas
authors.initials: J
authors.lastname: Schenk
authors.forename: Krisztina
authors.initials: K
authors.lastname: Balazs
authors.forename: Carmen
authors.initials: C
authors.lastname: Jungo
authors.forename: Julien
authors.initials: J
authors.lastname: Urfer
authors.forename: Carole
authors.initials: C
authors.lastname: Wegmann
authors.forename: Andrea
authors.initials: A
authors.lastname: Zocchi
authors.forename: Ian W
authors.initials: IW
authors.lastname: Marison
authors.forename: Urs
authors.initials: U
authors.lastname: von Stockar
mesh_terms: D001360:Avidin / Q000096:biosynthesis* / Q000378:metabolism; D019149:Bioreactors; D005285:Fermentation / Q000502:physiology; D006031:Glycosylation; D010843:Pichia / Q000235:genetics / Q000378:metabolism*; D011994:Recombinant Proteins / Q000096:biosynthesis*
chemical_list: D011994:Recombinant Proteins; D001360:Avidin