title: A chemostat study of Streptomyces peucetius var. caesius N47.
abstract: The behavior of Streptomyces peucetius var. caesius N47 was studied in a glucose limited chemostat with a complex cultivation medium. The steady-state study yielded the characteristic constants mu (max) over 0.10 h(-1), Y (XS) 0.536 g g(-1), and m(S) 0.54 mg g(-1) h(-1). The product of secondary metabolism, epsilon-rhodomycinone, was produced with characteristics Y (PX) 12.99 mg g(-1) and m (P) 1.20 mg g(-1) h(-1). Significant correlations were found for phosphate and glucose consumption with biomass and epsilon-rhodomycinone production. Metabolic flux analysis was conducted to estimate intracellular fluxes at different dilution rates. TCA, PPP, and shikimate pathway fluxes exhibited bigger values with production than with growth. Environmental perturbation experiments with temperature, airflow, and pH changes on a steady-state chemostat implied that an elevation of pH could be the most effective way to shift the cells from growing to producing, as the pH change induced the biggest transient increase to the calculated epsilon-rhodomycinone flux.
authors.affiliation: Laboratory of Bioprocess Engineering, Helsinki University of Technology, Helsinki, P.O. Box 6100, 02015 HUT, Finland. kristiina.kiviharju@tkk.fi
authors.forename: Kristiina
authors.initials: K
authors.lastname: Kiviharju
authors.forename: Ulla
authors.initials: U
authors.lastname: Moilanen
authors.forename: Matti
authors.initials: M
authors.lastname: Leisola
authors.forename: Tero
authors.initials: T
authors.lastname: Eerikäinen
mesh_terms: D018943:Anthracyclines / Q000378:metabolism; D001431:Bacteriological Techniques / Q000295:instrumentation / Q000379:methods; D019149:Bioreactors / Q000382:microbiology*; D005947:Glucose / Q000378:metabolism; D006863:Hydrogen-Ion Concentration; D010710:Phosphates / Q000378:metabolism; D013302:Streptomyces / Q000254:growth & development* / Q000378:metabolism*; D013696:Temperature
chemical_list: D018943:Anthracyclines; D010710:Phosphates; C015490:rhodomycinone; D005947:Glucose