title: De novo synthesis of monoterpenes by Saccharomyces cerevisiae wine yeasts.
abstract: This paper reports the production of monoterpenes, which elicit a floral aroma in wine, by strains of the yeast Saccharomyces cerevisiae. Terpenes, which are typical components of the essential oils of flowers and fruits, are also present as free and glycosylated conjugates amongst the secondary metabolites of certain wine grape varieties of Vitis vinifera. Hence, when these compounds are present in wine they are considered to originate from grape and not fermentation. However, the biosynthesis of monoterpenes by S. cerevisiae in the absence of grape derived precursors is shown here to be of de novo origin in wine yeast strains. Higher concentration of assimilable nitrogen increased accumulation of linalool and citronellol. Microaerobic compared with anaerobic conditions favored terpene accumulation in the ferment. The amount of linalool produced by some strains of S. cerevisiae could be of sensory importance in wine production. These unexpected results are discussed in relation to the known sterol biosynthetic pathway and to an alternative pathway for terpene biosynthesis not previously described in yeast.
authors.affiliation: Seccion Enologia, Departmento de Ciencia y Tecnologia de Alimentos, Facultad de Quimica, Universidad de la Republica, 11800 Montevideo, Uruguay. fcarrau@fq.edu.uy
authors.forename: Francisco M
authors.initials: FM
authors.lastname: Carrau
authors.forename: Karina
authors.initials: K
authors.lastname: Medina
authors.forename: Eduardo
authors.initials: E
authors.lastname: Boido
authors.forename: Laura
authors.initials: L
authors.lastname: Farina
authors.forename: Carina
authors.initials: C
authors.lastname: Gaggero
authors.forename: Eduardo
authors.initials: E
authors.lastname: Dellacassa
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Versini
authors.forename: Paul A
authors.initials: PA
authors.lastname: Henschke
mesh_terms: D000080462:Acyclic Monoterpenes; D003470:Culture Media; D015966:Gene Expression Regulation, Fungal; D039821:Monoterpenes / Q000378:metabolism*; D010084:Oxidation-Reduction; D012441:Saccharomyces cerevisiae / Q000254:growth & development / Q000378:metabolism*; D027843:Vitis / Q000378:metabolism; D014920:Wine / Q000382:microbiology*
chemical_list: D000080462:Acyclic Monoterpenes; D003470:Culture Media; D039821:Monoterpenes; C018584:linalool; C007078:citronellol