Investigation of weak organic acid tolerance mechanisms by lipidomic profiling of Saccharomyces cerevisiae and Zygosaccaromyces bailii

Conference poster, 2012

During pretreatment of lignocellulose raw material, compounds such as furaldehydes, phenolics and weak organic acids, severely inhibiting Saccharomyces cerevisiae, are released. Decrease of intracellular pH after diffusion through the plasma membrane is thought to be one of the effects mediating the cellular toxicity of weak organic acids. The aim of the present study is to investigate the relationship between plasma membrane composition and acid tolerance, in order to develop a strategy for engineering a S. cerevisiae strain more tolerant to acetic acid. Zygosaccharomyces bailii, a well-known food spoilage yeast, is highly tolerant to acetic acid and will be used as a model for weak organic acid tolerance. A complete lipidomic profiling of S. cerevisiae and Z. bailii in the presence and absence of acetic acid will be carried out using LC-MS/MS. Similarities and differences in the two profiles will be correlated with acid tolerance.