Abstract: The present invention relates to a ?5 desaturase, which has the ability to convert dihomo-?-linolenic acid (DGLA; 20:3 ?-6) to arachidonic acid (ARA; 20:4 ?-6) and/or eicosatetraenoic acid (ETA; 20:4 ?-3) to eicosapentaenoic acid (EPA; 20:5 ?-3). Isolated nucleic acid fragments and recombinant constructs comprising such fragments encoding ?5 desaturase along with a method of making long chain polyunsaturated fatty acids (PUFAs) using this ?5 desaturase in oleaginous yeast are disclosed.

Abstract: Engineered strains of the oleaginous yeast Yarrowia lipolytica capable of producing greater than 25% eicosapentaenoic acid (EPA, an ?-3 polyunsaturated fatty acid) in the total oil fraction are described. These strains comprise various chimeric genes expressing heterologous desaturases, elongases and acyltransferases and optionally comprise various native desaturase and acyltransferase knockouts to enable synthesis and high accumulation of EPA. Production host cells are claimed, as are methods for producing EPA within said host cells.

Abstract: Engineered strains of the oleaginous yeast Yarrowia lipolytica capable of producing greater than 10% arachidonic acid (ARA, an ?-6 polyunsaturated fatty acid) in the total oil fraction are described. These strains comprise various chimeric genes expressing heterologous desaturases, elongases and acyltransferases, and optionally comprise various native desaturase and acyltransferase knockouts to enable synthesis and high accumulation of ARA. Production host cells are claimed, as are methods for producing ARA within said host cells.

Abstract: The present invention relates to methods for the production of ?-linolenic acid (GLA) in oleaginous yeast. Thus, ?12 and ?6 desaturases able to catalyze the conversion of oleic acid to GLA have been introduced into the genome of Yarrowia, using zeta-directed integration. Transformed strains produced over 25% GLA in the total lipids, as opposed to wildtype Yarrowia that is unable to synthesize any GLA. Metabolic engineering and fermentation methods are provided to further enhance GLA productivity in oleaginous yeast.

Abstract: Mutant phytoene desaturase genes are provided encoding polypeptides having the ability to convert a phytoene desaturase substrate to tetradehydrolycopene. Both in vivo and in vitro methods are provided using the present phytoene desaturases for tetradehydrolycopene production.

Abstract: The regulatory sequences (i.e., promoter regions, introns and enhancers) associated with the Yarrowia lipolytica gene encoding fructose bis-phospate aldolase (FBA1) have been found to be particularly effective for the expression of heterologus genes in oleaginous yeast. The promoter regions of the invention have been shown to drive high-level expression of genes involved in the production of ?-3 and ?-6 fatty acids.