Understanding and exploiting the fatty acid desaturation system in Rhodotorula toruloides

Abstract Background Rhodotorula toruloides is a robust producer of triacylglycerol owing to its fast growth rate and strong metabolic flux under conditions high cell density fermentation. However, the molecular basis fatty acid biosynthesis, desaturation regulation remains elusive. Results We present characterization four desaturase (FAD) genes in R. . Biosynthesis oleic (OA) palmitoleic (POA) was conferred by single-copy ∆9 Fad (Ole1) as targeted deletion which abolished biosynthesis all unsaturated acids. Conversion OA linoleic (LA) α-linolenic (ALA) predominantly catalyzed bifunctional ∆12/∆15 Fad2. FAD4 found encode trifunctional ∆9/∆12/∆15 FAD, playing important roles lipid biomass production well stress resistance. Furthermore, an abundantly transcribed OLE1 -related gene, OLE2 encoding 149-aa protein, shown regulate Ole1 regioselectivity. Like other fungi, transcription FAD controlled nitrogen levels acids medium. A conserved DNA motif, (T/C)(G/A)TTGCAGA(T/C)CCCAG, demonstrated mediate POA/OA. The applications these were illustrated engineering high-level γ-linolenic (GLA). Conclusion Our work has gained novel insights on transcriptional genes, evolution enzymes their UFA membrane resistance and, mass total production. findings should illuminate beyond.