Bioactive Oxylipins inSaccharomyces cerevisiae

Abstract

Some strains of Saccharomyces cerevisiae (including strains used in fermentation processes) produce short chain (mainly 8 carbon) oxylipins and not potent inflammatory long chain (20 carbon) oxylipins such as prostaglandins. When acetylsalicylic acid (aspirin) was added to cultures of Sacch. cerevisiae UOFS Y-2330, flocculation was significantly inhibited as well as the production of 3-hydroxy 8:0 thereby linking flocculation and this oxylipin. Furthermore, no traces of 3-hydroxy 8:0 could be detected at the start of flocculation in this yeast. This research is based on (i) reports that yeasts in general can produce bioactive prostaglandins, (ii) findings suggesting a link between aspirinsensitive prostaglandins and biofilm formation by Candida albicans, (iii) the discovery that the addition of low concentrations of aspirin abolish yeast biofilm formation and sexual cell aggregation and (iv) the recent discovery of a novel potent aspirinsensitive pro-inflammatory 3-hydroxy prostaglandin E 2 synthesized by Candida albicans in conjunction with mammalian cells probably during candidiasis.

125th Anniversary Review: Yeast Flocculation and Sedimentation in Brewing

“…Higher ethanol concentrations 32 , lower growth temperatures 98 and higher pitching rates 33 all increase CSH. It has recently been proposed that hydrophobic oxylipins located at the cell surface of flocculating cells are a cause of increased CSH 88,90 . It has also been observed that cell surface hydrophobicity rises when FLO proteins are expressed 30,102 on the cell surface.…”

“…The presence of 3-OH oxylipins in strongly flocculating cells and their absence in weakly flocculent cells was observed 90 . When acetylsalicylic acid, a known 3-OH oxylipin inhibitor, was added to cultures of S. cerevisiae, both flocculation and the production of 3-OH oxylipins were significantly inhibited 88,90 . Oxylipins may increase the flocculation via their effect to increase cell surface hydrophobicity.…”

Mitochondrial Associated Yeast Flocculation -The Effect of Acetylsalicylic Acid

“…Therefore, this observation suggests that this oxylipin is associated with cell surface protuberances, as marked by immunofluorescing techniques, which play a role during flocculation 35 . When acetylsalicylic acid (ASA), a known 3-OH oxylipin inhibitor 7,13 , was added to cultures of S. cerevisiae, flocculation was significantly inhibited as well as the production of 3-OH 8:0 thereby linking flocculation and this oxylipin 35 . It is proposed that 3-OH oxylipins are produced by incomplete ␤-oxidation probably in the mitochondria of fungi 12 and then released and deposited on cell/ascospore surfaces 22 .…”

“…In later studies 35 , using gas chromatography-mass spectrometry (GC-MS), mainly 3-OH 8:0 was found to be associated with the flocculating vegetative cells of this yeast. Therefore, this observation suggests that this oxylipin is associated with cell surface protuberances, as marked by immunofluorescing techniques, which play a role during flocculation 35 .…”

“…It has been reported that ASA inhibits ␤-oxidation in mitochondria and thus 3-OH oxylipins synthesis 7,13 . Thus, literature suggests that mitochondrial function and yeast flocculation is interrelated 11,21,33,35 . The importance of mitochondrial function in yeast flocculation has also been further demonstrated by the use of drugs (i.e., antimycin A, ethionine) that inhibit mitochondrial function 9,18,27 and by cells that carry deletions in mitochondrial genes 16 and petite (respiratory deficient) mutants 10,17 .…”