The Mandelate Pathway, an Alternative to the Phenylalanine Ammonia Lyase Pathway for the Synthesis of Benzenoids in Ascomycete Yeasts

We present here evidence of the existence of the mandelate pathway in yeast for the synthesis of benzenoids. The link between phenylpyruvate- and 4-hydroxyphenlypyruvate-derived compounds with the corresponding synthesis of benzaldehydes through benzoylformate decarboxylation is demonstrated. Hanseniaspora vineae was used in these studies because of its capacity to produce benzenoid derivatives at a level 2 orders of magnitude higher than that produced by Saccharomyces . Contrary to what was hypothesized, neither β-oxidation derivatives nor 4-coumaric acid is an intermediate in the synthesis of yeast benzenoids. Our results might offer an answer to the long-standing question of the origin of 4-hydroxybenzoate for the synthesis of Q10 in humans.