PAD1 and FDC1 are essential for the decarboxylation of phenylacrylic acids in Saccharomyces cerevisiae

Abstract The volatile phenols, to which Saccharomyces cerevisiae converts from phenylacrylic acids including ferulic acid, p -coumaric acid, and cinnamic acid, generate off-flavors in alcoholic beverages such as beer and wine. Using gene disruptants, transformants and cell-free extracts of these strains, we have verified that the adjacent PAD1 (phenylacrylic acid decarboxylase, YDR538W ) and FDC1 (ferulic acid decarboxylase, YDR539W ) genes are essential for the decarboxylation of phenylacrylic acids in S. cerevisiae . Pad1p and Fdc1p are homologous with UbiX and UbiD, respectively, in the ubiquinone synthetic pathway of Escherichia coli . However, ubiquinone was detected quantitatively in all of the yeast single-deletion mutants, Δpad1 , Δfdc1 , and double-deletion mutant, Δpad1Δfdc1 .