Heterologous Production of Calendic Acid Naturally Found in  Calendula officinalis  by Recombinant Fission Yeast.
Calendic acid (CA) is a conjugated fatty acid with anti-cancer properties that is widely present in seed oil of  Calendula officinalis . Using the co-expression of  C. officinalis  fatty acid conjugases (CoFADX-1 or CoFADX-2) and  Punica granatum  fatty acid desaturase (PgFAD2), we metabolically engineered the synthesis of CA in the yeast  Schizosaccharomyces pombe  without the need for linoleic acid (LA) supplementation. The highest CA titer and achieved accumulation were 4.4 mg/L and 3.7 mg/g of DCW in PgFAD2 + CoFADX-2 recombinant strain cultivated at 16 °C for 72 h, respectively. Further analyses revealed the accumulation of CA in free fatty acids (FFA) and downregulation of the  lcf1  gene encoding long-chain fatty acyl-CoA synthetase. The developed recombinant yeast system represents an important tool for the future identification of the essential components of the channeling machinery to produce CA as a high-value conjugated fatty acid at an industrial level.
Garaiova M, Hua Q, Holic R