Open AccessA new physiological role for Pdr12p in Saccharomyces cerevisiae : export of aromatic and branched‐chain organic acids produced in amino acid catabolism
Author(s) -
Hazelwood Lucie A.,
Tai Siew Leng,
Boer Viktor M.,
De Winde Johannes H.,
Pronk Jack T.,
Daran Jean Marc
Publication year - 2006
Publication title -
fems yeast research
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.991
H-Index - 92
eISSN - 1567-1364
pISSN - 1567-1356
DOI - 10.1111/j.1567-1364.2006.00094.x
Subject(s) - fusel alcohol , biochemistry , amino acid , phenylalanine , biology , methionine , saccharomyces cerevisiae , isoleucine , leucine , isobutanol , yeast , valine , aromatic amino acids , catabolism , tyrosine , tryptophan , branched chain amino acid , metabolism , fermentation , alcohol
Saccharomyces cerevisiae can use a broad range of compounds as sole nitrogen source. Many amino acids, such as leucine, tyrosine, phenylalanine and methionine, are utilized through the Ehrlich pathway. The fusel acids and alcohols produced from this pathway, along with their derived esters, are important contributors to beer and wine flavor. It is unknown how these compounds are exported from the cell. Analysis of nitrogen‐source‐dependent transcript profiles via microarray analysis of glucose‐limited, aerobic chemostat cultures revealed a common upregulation of PDR12 in cultures grown with leucine, methionine or phenylalanine as sole nitrogen source. PDR12 encodes an ABC transporter involved in weak‐organic‐acid resistance, which has hitherto been studied in the context of resistance to exogenous organic acids. The hypothesis that PDR12 is involved in export of natural products of amino acid catabolism was evaluated by analyzing the phenotype of null mutants in PDR12 or in WAR1 , its positive transcriptional regulator. The hypersensitivity of the pdr12 Δ and war1 Δ strains for some of these compounds indicates that Pdr12p is involved in export of the fusel acids, but not the fusel alcohols derived from leucine, isoleucine, valine, phenylalanine and tryptophan.