title: Effect of flow rate pattern on glucose-6-phosphate dehydrogenase synthesis in fed-batch culture of recombinant Saccharomyces cerevisiae.
abstract: A strain of genetically modified Saccharomyces cerevisiae (S. cerevisiae) W303 181 was used to improve glucose-6-phosphate dehydrogenase (G6PDH) production in aerobic culture. Fed-batch cultures were carried out in a 5 L fermentor at variable values of the parameter K, namely, 0.2, 0.3, 0.5, 0.7, and 0.8 h(-)(1). The highest G6PDH production (1164 U/L) and specific activity (517 U/g(cell)) were obtained using the following conditions: glucose, 5.0 g/L; adenine, 8 microg/mL; histidine, 8 microg/mL; tryptophan, 8 microg/mL; temperature, 30 degrees C; inoculum, 1.28 g/L; pH, 5.7; agitation, 400 rpm; aeration, 2.2 vvm; and K, 0.2 h(-)(1). The exponential feeding pattern increased cell density (2.14 g/L), enzyme productivity (149.27), and biomass yield (0.18 g(glu)/g(cell)( )(mass)). The level of G6PDH in the genetically modified S. cerevisiae was approximately 4.1-fold higher than that found in a commercial strain.
authors.affiliation: Biochemical-Pharmaceutical Technology Department, FCF, University of São Paulo, Av. Prof. Lineu Prestes, 580/B16, 05508-900 São Paulo, SP, Brazil.
authors.forename: Angelo Samir Melim
authors.initials: AS
authors.lastname: Miguel
authors.forename: Luiz Carlos
authors.initials: LC
authors.lastname: Martins das Neves
authors.forename: Michele
authors.initials: M
authors.lastname: Vitolo
authors.forename: Adalberto
authors.initials: A
authors.lastname: Pessoa
mesh_terms: D019149:Bioreactors / Q000382:microbiology*; D018929:Cell Culture Techniques / Q000379:methods*; D002455:Cell Division; D004789:Enzyme Activation; D005947:Glucose / Q000378:metabolism*; D005954:Glucosephosphate Dehydrogenase / Q000096:biosynthesis* / Q000235:genetics; D008954:Models, Biological; D011994:Recombinant Proteins / Q000096:biosynthesis; D012212:Rheology / Q000379:methods*; D012441:Saccharomyces cerevisiae / Q000166:cytology / Q000201:enzymology* / Q000235:genetics*
chemical_list: D011994:Recombinant Proteins; D005954:Glucosephosphate Dehydrogenase; D005947:Glucose