title: Intensification of high cell-density cultivations of rE. coli for production of S. pneumoniae antigenic surface protein, PspA3, using model-based adaptive control.
abstract: This work proposes an innovative methodology to control high density fed-batch cultures of E. coli, based on measurements of the concentration of dissolved oxygen and on estimations of the cellular specific growth rate (µ), of the yield of biomass/limiting substrate (Y                         (xs)) and of the maintenance coefficient (m). The underlying idea is to allow cells to grow according to their metabolic capacity, without the constraints inherent to pre-set growth rates. Cellular concentration was assessed on-line through a capacitance probe. Three configurations of the control system were compared: (1) pre-set value for the three control parameters; (2) continuously updating µ; (3) updating µ, Y                         (xs) and m. Implementation of an efficient noise filter for the signal of the capacitance probe was essential for a good performance of the control system. The third control strategy, within the framework of an adaptive model-based control, led to the best results, with biomass productivity reaching 9.2 g(DCW)/L/h.
authors.affiliation: Departamento de Engenharia Química, Universidade Federal de São Carlos, São Carlos, SP, Brazil.
authors.forename: Antonio Carlos Luperni
authors.initials: AC
authors.lastname: Horta
authors.forename: Cíntia Regina
authors.initials: CR
authors.lastname: Sargo
authors.forename: Adilson José
authors.initials: AJ
authors.lastname: da Silva
authors.forename: Marina
authors.initials: M
authors.lastname: de Carvalho Gonzaga
authors.forename: Maurício Possedente
authors.initials: MP
authors.lastname: Dos Santos
authors.forename: Viviane Maimoni
authors.initials: VM
authors.lastname: Gonçalves
authors.forename: Teresa Cristina
authors.initials: TC
authors.lastname: Zangirolami
authors.forename: Roberto
authors.initials: R
authors.lastname: de Campos Giordano
mesh_terms: D001426:Bacterial Proteins / Q000096:biosynthesis* / Q000235:genetics; D019149:Bioreactors; D004926:Escherichia coli / Q000235:genetics / Q000254:growth & development* / Q000378:metabolism*; D008954:Models, Biological; D010101:Oxygen Consumption / Q000502:physiology; D011994:Recombinant Proteins / Q000096:biosynthesis / Q000235:genetics; D013296:Streptococcus pneumoniae / Q000235:genetics*
chemical_list: D001426:Bacterial Proteins; D011994:Recombinant Proteins; C051592:pneumococcal surface protein A