Variation in Nitrogen Source Utilization among Six Strains of <i>S. cerevisiae</i>

<div><p>Each square represents the growth of one strain in the PM assay supplied with the indicated nitrogen source. The value reflecting the extent of growth was generated from the 48-h signal curve of the PM assay and represented by the intensity of coloration, as shown in the legend. All signal values exceeding 200 reflected very robust growth, and are therefore represented with the same color. Blue-bordered squares denote nitrogen sources that produced varying results in that strain, exhibiting substantial variation in signal among replicates (σ²/mean >10 and at least one replicate with signal >50 or <200). Red-bordered squares denote putative substrates of the Asp3p asparaginase.</p><p>(A) Amino acids, (B) N-end rule dipeptides, (C) non–N-end rule dipeptides, (D) tripeptides; amino acids are represented as single letters, and (E) miscellaneous nitrogen sources.</p>