title: Amino acid supplementation improves heterologous protein production by Saccharomyces cerevisiae in defined medium.
abstract: Supplementation of a chemically defined medium with amino acids or succinate to improve heterologous xylanase production by a prototrophic Saccharomyces cerevisiae transformant was investigated. The corresponding xylanase production during growth on ethanol in batch culture and in glucose-limited chemostat culture were quantified, as the native ADH2 promoter regulating xylanase expression was derepressed under these conditions. The addition of a balanced mixture of the preferred amino acids, Ala, Arg, Asn, Glu, Gln and Gly, improved both biomass and xylanase production, whereas several other individual amino acids inhibited biomass and/or xylanase production. Heterologous protein production by the recombinant yeast was also improved by supplementing the medium with succinate. The production of heterologous xylanase during growth on ethanol or glucose could thus be improved by supplementing metabolic precursors in the carbon- or nitrogen-metabolism.
authors.affiliation: Department of Applied Microbiology, Lund University, Box 124, 221 00 Lund, Sweden.
authors.forename: Johann F
authors.initials: JF
authors.lastname: Görgens
authors.forename: Willem H
authors.initials: WH
authors.lastname: van Zyl
authors.forename: Johannes H
authors.initials: JH
authors.lastname: Knoetze
authors.forename: Bärbel
authors.initials: B
authors.lastname: Hahn-Hägerdal
mesh_terms: D000596:Amino Acids / Q000378:metabolism*; D018533:Biomass; D003470:Culture Media / Q000737:chemistry*; D043364:Endo-1,4-beta Xylanases / Q000096:biosynthesis*; D000431:Ethanol / Q000378:metabolism; D005947:Glucose / Q000378:metabolism; D011994:Recombinant Proteins / Q000096:biosynthesis*; D012441:Saccharomyces cerevisiae / Q000235:genetics / Q000254:growth & development / Q000378:metabolism*; D019802:Succinic Acid / Q000378:metabolism
chemical_list: D000596:Amino Acids; D003470:Culture Media; D011994:Recombinant Proteins; D000431:Ethanol; D019802:Succinic Acid; D043364:Endo-1,4-beta Xylanases; D005947:Glucose