title: Influence of the hydromechanical stress and temperature on growth and antibody fragment production with Bacillus megaterium.
abstract: Bacillus megaterium was used for production of the lysozyme-specific recombinant scFv D1.3 antibody fragment. Key process parameters like the temperature and the hydromechanical stress play a very important role for significant product formation during process development or scale-up. In this study, the influence of these two variables on growth and recombinant antibody fragment production in a 2-L lab-scale bioreactor system was investigated using a central composite design. Especially a significant influence of the hydromechanical stress on antibody fragment production was detected in batch cultivations. While volumetric power inputs of about 0.5 kW/m(3) (agitation rates around 500 min(-1)) are usually employed in batch cultivations, in this work maximal product concentration was found at a volumetric power input of about 0.06 kW/m(3) (agitation rate around 250 min(-1)) and at a high cultivation temperature of 41 °C. The influence of the two process variables at single-cell level was estimated using flow cytometry too. The characterization was done by estimating the membrane potential giving a hint on bioprocess productivity and secretion capability: the best production was obtained through big cells with low specific membrane potential, which grew at low volumetric power inputs and high cultivation temperatures.
authors.affiliation: Institute of Biochemical Engineering, Technische Universität Braunschweig, Gausstrasse 17, Braunschweig, Germany.
authors.forename: Svenja
authors.initials: S
authors.lastname: Lüders
authors.forename: Florian
authors.initials: F
authors.lastname: David
authors.forename: Miriam
authors.initials: M
authors.lastname: Steinwand
authors.forename: Eva
authors.initials: E
authors.lastname: Jordan
authors.forename: Michael
authors.initials: M
authors.lastname: Hust
authors.forename: Stefan
authors.initials: S
authors.lastname: Dübel
authors.forename: Ezequiel
authors.initials: E
authors.lastname: Franco-Lara
mesh_terms: D001410:Bacillus megaterium / Q000737:chemistry / Q000235:genetics / Q000254:growth & development* / Q000378:metabolism*; D001696:Biomechanical Phenomena; D019149:Bioreactors / Q000382:microbiology; D003470:Culture Media; D007218:Industrial Microbiology / Q000379:methods*; D011994:Recombinant Proteins / Q000096:biosynthesis / Q000235:genetics; D057127:Single-Chain Antibodies / Q000096:biosynthesis* / Q000235:genetics; D013696:Temperature
chemical_list: D003470:Culture Media; D011994:Recombinant Proteins; D057127:Single-Chain Antibodies