Overproduction of isoprenoids by Saccharomyces cerevisiae in a synthetic grape juice medium in the absence of plant genes

CAMESASCA, L.; MINTEGUIAGA, M.; FARIÑA, L.; SALZMAN, V.; AGUILAR, P.S.; GAGGERO, C.; CARRAU, F.

INTERNATIONAL JOURNAL OF FOOD MICROBIOLOGY

ELSEVIER SCIENCE BV

Lugar: Amsterdam; Año: 2018 vol. 282 p. 42 - 48

0168-1605

The objective of this work is to demonstrate if the hexaprenyl pyrophosphate synthetase Coq1p might be in-volved in monoterpenes synthesis in Saccharomyces cerevisiae, although its currently known function in yeast isto catalyze the first step in ubiquinone biosynthesis. However, in a BY4743 laboratory strain, the presence of anempty plasmid in a chemically defined grape juice medium results in a statistically significant increase of li-nalool, (E)-nerolidol and (E,E)-farnesol. When COQ1 is overexpressed from a plasmid, the levels of the volatileisoprenoids are further increased. Furthermore, overexpression of COQ1 in the same genetic context but with amutated farnesyl pyrophosphate synthetase (erg20 mutation K197E), results in statistically significant higherlevels of linalool (above 750 μg/L), geraniol, α-terpineol, and the sesquiterpenes, farnesol and nerolidol (totalconcentration of volatile isoprenoids surpasses 1300 μg/L). We show that the levels of monoterpenes and ses-quiterpenes that S. cerevisiae can produce, in the absence of plant genes, depend on the composition of themedium and the genetic context. To the best of our knowledge, this is the highest level of linalool produced by S.cerevisiae up to now. Further research will be needed for understanding how COQ1 and the medium compositionmight interact to increase flavor complexity of fermented beverages.