Sphingolipid and sterol profiles of <i>S. cerevisiae</i> and <i>Z. bailii</i> in response to acetic acid.

<p>Sc: <i>S. cerevisiae</i> cultured in minimal medium. ScAA: <i>S. cerevisiae</i> cultured in minimal medium with 9 g L⁻¹ acetic acid. Zb: <i>Z. bailii</i> cultured in minimal medium. ZbAA: <i>Z. bailii</i> cultured in minimal medium with 24 g L⁻¹ acetic acid. Apparent quantities were calculated relative to the appropriate internal standard, and normalized to the total amount of phosphate in each sample (see Materials and Methods). <b>A.</b> Head group classes of complex sphingolipids. <b>B.</b> Total sphingolipid chain length, presented per lipid, containing two fatty acyl chains. <b>C.</b> Total ceramides and ceramide sub-classes. Abbreviations: DHS: dihydrosphingosine, PHS: phytosphingosine. <b>D.</b> Ergosterol, ergosterol esters and total sterols. *Significant differences, obtained by t-test (P<0.05) compared with control condition (Sc or Zb). The results were calculated from biological replicates (n = 4) and are given as the mean ± standard deviation. For lipid nomenclature, see <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0073936#pone-0073936-t001" target="_blank">Table 1</a>.