A Novel Soybean Diacylglycerol Acyltransferase 1b Variant with Three Amino Acid Substitutions Increases Seed Oil Content.

Improving soybean (Glycine max) seed composition by increasing the protein and oil components will add significant value to the crop and enhance environmental sustainability. Diacylglycerol acyltransferase (DGAT) catalyzes the final rate-limiting step in triacylglycerol biosynthesis and has a major impact on seed oil accumulation. We previously identified a soybean DGAT1b variant modified with 14 amino acid substitutions (GmDGAT1b-MOD) that increases total oil content by 3 percentage points when overexpressed in soybean seeds.

An Improved Variant of Soybean Type 1 Diacylglycerol Acyltransferase Increases the Oil Content and Decreases the Soluble Carbohydrate Content of Soybeans.

Kinetically improved diacylglycerol acyltransferase (DGAT) variants were created to favorably alter carbon partitioning in soybean (Glycine max) seeds. Initially, variants of a type 1 DGAT from a high-oil, high-oleic acid plant seed, Corylus americana, were screened for high oil content in Saccharomyces cerevisiae Nearly all DGAT variants examined from high-oil strains had increased affinity for oleoyl-CoA, with S0.5 values decreased as much as 4.

Identification of bifunctional delta12/omega3 fatty acid desaturases for improving the ratio of omega3 to omega6 fatty acids in microbes and plants.

We report the identification of bifunctional Delta12/omega3 desaturases from Fusarium moniliforme, Fusarium graminearum, and Magnaporthe grisea. The bifunctional activity of these desaturases distinguishes them from all known Delta12 or omega3 fatty acid desaturases. The omega3 desaturase activity of these enzymes also shows a broad omega6 fatty acid substrate specificity by their ability to convert linoleic acid (LA), gamma-linolenic acid, di-homo-gamma-linolenic acid, and arachidonic acid to the omega3 fatty acids, alpha-linolenic acid (ALA), stearidonic acid, eicosatetraenoic acid, and eicosapentaenoic acid (EPA), respectively.

Metabolic redesign of vitamin E biosynthesis in plants for tocotrienol production and increased antioxidant content.

Tocotrienols are the primary form of vitamin E in seeds of most monocot plants, including cereals such as rice and wheat. As potent antioxidants, tocotrienols contribute to the nutritive value of cereal grains in human and livestock diets. cDNAs encoding homogentisic acid geranylgeranyl transferase (HGGT), which catalyzes the committed step of tocotrienol biosynthesis, were isolated from barley, wheat and rice seeds.

Transgenic production of epoxy fatty acids by expression of a cytochrome P450 enzyme from Euphorbia lagascae seed.

Seed oils of a number of Asteraceae and Euphorbiaceae species are enriched in 12-epoxyoctadeca-cis-9-enoic acid (vernolic acid), an unusual 18-carbon Delta(12)-epoxy fatty acid with potential industrial value. It has been previously demonstrated that the epoxy group of vernolic acid is synthesized by the activity of a Delta(12)-oleic acid desaturase-like enzyme in seeds of the Asteraceae Crepis palaestina and Vernonia galamensis. In contrast, results from metabolic studies have suggested the involvement of a cytochrome P450 enzyme in vernolic acid synthesis in seeds of the Euphorbiaceae species Euphorbia lagascae.