Isolation and genetic study of p-fluoro-dl-phenylalanine-resistant mutants overproducing β-phenethyl-alcohol in Saccharomyces cerevisiae

Abstract

p-Fluoro-dl-phenylalanine (PFP)-resistant mutants which produce a large amount of β-phenethyl-alcohol, a rose-like flavor component, were isolated from the isogenic strains X2180-1A and X2180-1B of Saccharomyces cerevisiae. Cells of these mutants accumulated phenylalanine and tryptophan more than 3-fold times that of wild-type cells, while they accumulated less than half the tyrosine. The activity of prephenate dehydrogenase (PDG) (EC 1.3.1.12) was markedly decreased while that of 3-deoxy-d-arabino-heptulosonate-7-phosphate synthase (EC 4.1.2.15) was increased. Genetic analysis revealed that the mutation occurred at the TYR1 locus, encoding PDG, and that the mutated TYR1 gene, tyr1-pfp, caused both PFP resistance and β-phenethyl-alcohol overproduction. This was supported by molecular genetic studies with cloned tyr1-pfp DNA. © 1991 Springer-Verlag.