Yarrowia lipolytica as a Platform for Punicic Acid Production

Area of Science:

• Biotechnology
• Metabolic Engineering
• Industrial Microbiology

Background:

• Punicic acid (PuA), a unique polyunsaturated fatty acid, possesses significant nutraceutical and biological properties.
• Current PuA production relies on pomegranate seed oil, necessitating sustainable and efficient alternative sources.
• Previous attempts using recombinant microorganisms and plants for PuA production yielded limited success.

Purpose of the Study:

• To engineer the oleaginous yeast Yarrowia lipolytica for the de novo production of punicic acid (PuA).
• To evaluate Y. lipolytica as a sustainable microbial platform for PuA biosynthesis.

Main Methods:

• Yarrowia lipolytica was cultivated in media supplemented with pomegranate seed oil to assess lipid and PuA accumulation.
• Lipid-engineered Y. lipolytica strains were created by introducing the bifunctional fatty acid conjugase/desaturase (PgFADX) from Punica granatum.
• Promoter optimization strategies were employed to enhance PgFADX expression and maximize PuA production.

Main Results:

• Cultivation in pomegranate seed oil-supplemented media resulted in Y. lipolytica accumulating 31.2% lipids, with 22% being PuA.
• Engineered Y. lipolytica strains expressing PgFADX successfully synthesized PuA de novo, detected in both polar and neutral lipid fractions.
• Optimized PgFADX expression led to a significant increase in PuA accumulation, reaching 1.8 mg/g dry cell weight, with the best strain producing 36.6 mg/L PuA.

Conclusions:

• Yarrowia lipolytica serves as a highly promising and efficient host for the sustainable de novo production of punicic acid.
• Metabolic engineering of Y. lipolytica offers a viable strategy to overcome limitations associated with traditional PuA sourcing.
• This study establishes a foundation for further development of yeast-based platforms for PuA and other valuable fatty acid production.