|Engineering Saccharomyces cerevisiae to release 3-Mercaptohexan-1-ol during fermentation through overexpression of an S. cerevisiae Gene, STR3, for improvement of wine aroma.
|Year of Publication
|Holt, S, Cordente, AG, Williams, SJ, Capone, DL, Jitjaroen, W, Menz, IR, Curtin, CD, Anderson, PA
|Appl Environ Microbiol
|DNA, Fungal, Fermentation, Gene Expression, Lyases, Molecular Sequence Data, Saccharomyces cerevisiae, Saccharomyces cerevisiae Proteins, Sequence Analysis, DNA, Sulfhydryl Compounds, Vitis, Wine
Sulfur-containing aroma compounds are key contributors to the flavor of a diverse range of foods and beverages. The tropical fruit characters of Vitis vinifera L. cv. Sauvignon blanc wines are attributed to the presence of the aromatic thiols 3-mercaptohexan-1-ol (3MH), 3-mercaptohexan-1-ol-acetate, and 4-mercapto-4-methylpentan-2-one (4MMP). These volatile thiols are found in small amounts in grape juice and are formed from nonvolatile cysteinylated precursors during fermentation. In this study, we overexpressed a Saccharomyces cerevisiae gene, STR3, which led to an increase in 3MH release during fermentation of a V. vinifera L. cv. Sauvignon blanc juice. Characterization of the enzymatic properties of Str3p confirmed it to be a pyridoxal-5'-phosphate-dependent cystathionine β-lyase, and we demonstrated that this enzyme was able to cleave the cysteinylated precursors of 3MH and 4MMP to release the free thiols. These data provide direct evidence for a yeast enzyme able to release aromatic thiols in vitro that can be applied in the development of self-cloned yeast to enhance wine flavor.
|Appl. Environ. Microbiol.
|PubMed Central ID