title: A metabolic engineering strategy for producing conjugated linoleic acids using the oleaginous yeast Yarrowia lipolytica.
abstract: Conjugated linoleic acids (CLAs) have been found to have beneficial effects on human health when used as dietary supplements. However, their availability is limited because pure, chemistry-based production is expensive, and biology-based fermentation methods can only create small quantities. In an effort to enhance microbial production of CLAs, four genetically modified strains of the oleaginous yeast Yarrowia lipolytica were generated. These mutants presented various genetic modifications, including the elimination of β-oxidation (pox1-6∆), the inability to store lipids as triglycerides (dga1∆ dga2∆ are1∆ lro1∆), and the overexpression of the Y. lipolytica ∆12-desaturase gene (YlFAD2) under the control of the constitutive pTEF promoter. All strains received two copies of the pTEF-oPAI or pPOX-oPAI expression cassettes; PAI encodes linoleic acid isomerase in Propionibacterium acnes. The strains were cultured in neosynthesis or bioconversion medium in flasks or a bioreactor. The strain combining the three modifications mentioned above showed the best results: when it was grown in neosynthesis medium in a flask, CLAs represented 6.5% of total fatty acids and in bioconversion medium in a bioreactor, and CLA content reached 302 mg/L. In a previous study, a CLA degradation rate of 117 mg/L/h was observed in bioconversion medium. Here, by eliminating β-oxidation, we achieved a much lower rate of 1.8 mg/L/h.
authors.affiliation: Micalis Institute, INRA, AgroParisTech, Université Paris-Saclay, 78350, Jouy-en-Josas, France. nabila.imatoukene@utc.fr.|Sorbonne Universités, EA 4297 TIMR, Université de Technologie de Compiègne (UTC), rue Personne de Roberval, F-60203, Compiègne, France. nabila.imatoukene@utc.fr.
authors.forename: Nabila
authors.initials: N
authors.lastname: Imatoukene
authors.affiliation: Micalis Institute, INRA, AgroParisTech, Université Paris-Saclay, 78350, Jouy-en-Josas, France.
authors.forename: Jonathan
authors.initials: J
authors.lastname: Verbeke
authors.affiliation: Micalis Institute, INRA, AgroParisTech, Université Paris-Saclay, 78350, Jouy-en-Josas, France.
authors.forename: Athanasios
authors.initials: A
authors.lastname: Beopoulos
authors.affiliation: Sorbonne Universités, FRE-CNRS 3580 GEC, Université de Technologie de Compiègne (UTC), rue Personne de Roberval, F-60203, Compiègne, France.
authors.forename: Abdelghani
authors.initials: A
authors.lastname: Idrissi Taghki
authors.affiliation: Sorbonne Universités, FRE-CNRS 3580 GEC, Université de Technologie de Compiègne (UTC), rue Personne de Roberval, F-60203, Compiègne, France.
authors.forename: Brigitte
authors.initials: B
authors.lastname: Thomasset
authors.affiliation: Sorbonne Universités, EA 4297 TIMR, Université de Technologie de Compiègne (UTC), rue Personne de Roberval, F-60203, Compiègne, France.
authors.forename: Claude-Olivier
authors.initials: CO
authors.lastname: Sarde
authors.affiliation: Sorbonne Universités, EA 4297 TIMR, Université de Technologie de Compiègne (UTC), rue Personne de Roberval, F-60203, Compiègne, France.
authors.forename: Maurice
authors.initials: M
authors.lastname: Nonus
authors.affiliation: Micalis Institute, INRA, AgroParisTech, Université Paris-Saclay, 78350, Jouy-en-Josas, France. jean-marc.nicaud@inra.fr.
authors.forename: Jean-Marc
authors.identifier: http://orcid.org/0000-0002-6679-972X
authors.initials: JM
authors.lastname: Nicaud
mesh_terms: D019149:Bioreactors; D044943:Fatty Acid Desaturases / Q000235:genetics / Q000378:metabolism; D005285:Fermentation; D005656:Fungal Proteins / Q000235:genetics* / Q000378:metabolism; D006801:Humans; D007535:Isomerases / Q000235:genetics / Q000378:metabolism; D044243:Linoleic Acids, Conjugated / Q000096:biosynthesis*; D008055:Lipids / Q000096:biosynthesis; D060847:Metabolic Engineering / Q000379:methods*; D010084:Oxidation-Reduction; D011401:Promoter Regions, Genetic; D011425:Propionibacterium acnes / Q000201:enzymology / Q000235:genetics; D025062:Yarrowia / Q000235:genetics* / Q000378:metabolism*
chemical_list: D005656:Fungal Proteins; D044243:Linoleic Acids, Conjugated; D008055:Lipids; D044943:Fatty Acid Desaturases; D007535:Isomerases
keywords: Conjugated linoleic acids; Lipid accumulation; Metabolic engineering; Oleaginous yeast; Yarrowia lipolytica