Production of 3R‐hydroxy‐polyenoic fatty acids by the yeast Dipodascopsis uninucleata

Abstract

Various fatty acids were fed to the yeast Dipodascopsis uninucleata UOFS Y 128, and the extracted samples were analyzed for the accumulation of 3-hydroxy metabolites with the help of electron impact gas chromatography-mass spectrometry. Fatty acids containing of 5Z,8Z-diene system (5Z,8Z,11Z-eicosatrienoic, 5Z,8Z,11Z,14Z-eicosatetraenoic, and 5Z,8Z,11Z,14Z,17Z-eicosapentaenoic acids) yielded the corresponding 3-hydroxy-all-Z-eicosapolyenoic acids. Moreover, linoleic acid (9Z,12Z-octadecadienoic acid) and 11Z,14Z,17Z-eicosatrienoic acid were converted to the 3-hydorxylated metabolites of shorter chain length, e,g., 3-hydroxy-5Z,8Z-tetradecadienoic acid and 3-hydroxy-5Z,8Z,11Z-tetradecatrienoic acid, respectively. In contrast, no accumulation of a 3-hydroxy metabolite was observed with oleic acid (9Z-octadecenoic acid), linolelaidic acid (9E,12E-octadecadienoic acid), gamma-linolenic acid (6Z,9Z,12Z-octadecatrienoic acid), and eicosanoic acid as substrate. These findings pinpoint that the 3-hydroxylation of a fatty acid in Dipodascopsis uninucleata requires a 5Z,8Z-diene system either directly or following initial incomplete beta-oxidation. Following analysis of the enantiomer composition, the arachidonic acid metabolite was identified as 3R-hydroxy-5Z,8Z,11Z,14Z-eicosatetraenoic acid, which rules out a normal beta-oxidation as biosynthetic route to this new class of oxylipins.

Oxylipin covered ascospores of Eremothecium coryli

“…The GC -MS was auto-tuned for m/z of 50 -502. Each sample (1 ll) was injected into the GC -MS at a split ratio of 1:20 at an inlet temperature of 250°C (Venter et al 1997).…”

Synthesis of tritium labelled 3(R)‐HETE and 3(R),18(R/S)‐DiHETE through a common synthetic route

“…Recently, we have reported a fast and efficient method for the preparation of 3(R)-HETE via its tetraacetylenic precursor. 6 Here we extend its application to the synthesis of tritium labelled 3(R)-HETE (2). As illustrated in Scheme 1, stereospecific …”

“…Prior to use all glassware and syringes were dried at 1408C overnight and all reactions were carried out under an atmosphere of dry argon. [5,6,8,9,11,12,14,15-3 H]-(3R,5Z,8Z,11Z,14Z)-3-Hydroxyeicosa-5,8,11,14-tetraenoic acid (2) A solution of 1 (20 mg, 0.06 mmol) in benzene (1 ml), Lindlar's catalyst (35 mg) and quinoline (0.03 ml) were placed in the reaction ampoule and the mixture was frozen with liquid nitrogen. After evacuation the ampoule was filled with a hydrogen-tritium mixture, containing 1% of tritium, up to a pressure of 400 hPa.…”

“…After the H 2 absorption was complete, the mixture was filtered and the filtrate was washed with HCl (2 M, 2 Â 50 ml). Evaporation of the solvent yielded a crude residue, which was purified by preparative RP-HPLC (MeOH/H 2 (3R,18R/S,5Z,8Z,11Z,14Z)-3,18-Dihydroxyeicosa-5,8,11,14-tetraenoic acid (7) An aqueous solution of NaOH (0.33 M, 10 ml) was added under argon to a solution of ester 6 (102 mg, 0.22 mmol) in MeOH (15 ml). The mixture was stirred for 40 h at room temperature, MeOH was removed by evaporation, and the pH was adjusted carefully to 5.0 using HCl (1 M).…”

Involvement of aspirin-sensitive oxylipins in vulvovaginal candidiasis

“…This compound belongs to a particular group of oxygenated fatty acid metabolites, the 3(R)-hydroxyoxylipins, the occurrence of which has been ¢rst uncovered in the non-pathogenic yeast Dipodascopsis uninucleata [9,10] and later in Mucor genevensis [11] and other fungal species belonging to the Lipomycetaceae, Dipodascaceae and Mucorales. In D. uninucleata, endogenous 3(R)-hydroxyoxylipins have been found to be intimately connected with the sexual stage of the life cycle of the yeast, as determined by immuno£uorescence microscopy [12].…”