Open AccessTranscriptional responses of Saccharomyces cerevisiae to preferred and nonpreferred nitrogen sources in glucose‐limited chemostat cultures
Author(s) -
Boer Viktor M.,
Tai Siew Leng,
Vuralhan Zeynep,
Arifin Yalun,
Walsh Michael C.,
Piper Matthew D.W.,
De Winde Johannes H.,
Pronk Jack T.,
Daran JeanMarc
Publication year - 2007
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.1567-1364.2007.00220.x
Subject(s) - chemostat , biology , asparagine , saccharomyces cerevisiae , biochemistry , methionine , asparagine synthetase , leucine , phenylalanine , ammonium , yeast , amino acid , genetics , chemistry , bacteria , organic chemistry
Aerobic, glucose‐limited chemostat cultures of Saccharomyces cerevisiae grown with six different nitrogen sources were subjected to transcriptome analysis. The use of chemostats enabled an analysis of nitrogen‐source‐dependent transcriptional regulation at a fixed specific growth rate. A selection of preferred (ammonium and asparagine) and nonpreferred (leucine, phenylalanine, methionine and proline) nitrogen sources was investigated. For each nitrogen source, distinct sets of genes were induced or repressed relative to the other five nitrogen sources. In total, 131 such ‘signature transcripts’ were identified in this study. In addition to signature transcripts, genes were identified that showed a transcriptional coresponse to two or more of the six nitrogen sources. For example, 33 genes were transcriptionally upregulated in leucine‐grown, phenylalanine‐grown and methionine‐grown cultures; this was partly attributed to the involvement of common enzymes in the dissimilation of these amino acids. In addition to specific transcriptional responses elicited by individual nitrogen sources, their impact on global regulatory mechanisms such as nitrogen catabolite repression (NCR) were monitored. NCR‐sensitive gene expression in the chemostat cultures showed that ammonium and asparagine were ‘rich’ nitrogen sources. By this criterion, leucine, proline and methionine were ‘poor’ nitrogen sources, and phenylalanine showed an ‘intermediate’ NCR response.