The mechanism of the formation of tyrosol by Saccharomyces cerevisiae

Abstract

Washed-cell suspensions of S. cerevisiae form tyrosol from L-tyrosine anaerobically in the presence of glucose, which is essential. Formation of tyrosol by whole cells is inhibited by 2,4-dinitrophenol and sodium azide. Cell-free extracts of S. cerevisiae incubated with 2-oxoglutarate and tyrosine form p-hydroxyphenylacetaldehyde, glutamic acid and carbon dioxide. The reaction is stimulated by pyridoxal phosphate. Cell-free extracts of S. cerevisiae decarboxylatep-hydroxyphenylpyruvate. Cell-free extracts oxidize reduced diphosphopyridine nucleotide on addition of p-hydroxyphenylacetaldehyde. It is suggested that the formation of fusel oil involves the successive action of a transaminase, carboxylase and the alcohol dehydrogenase.