Engineering production of C18 conjugated fatty acids in developing seeds of oil crops

Polyunsaturated fatty acids (PUFAs) with at least one pair of double bonds which are separated by only a single bond are known as conjugated fatty acids (CFAs). These types of fatty acids (FAs) are subject to a relatively high rate of oxidation and have subsequently found industrial applications in the production of organic coatings and polymers. From a dietary perspective, there is also a growing body of information which suggests that CFAs are useful in slowing the growth of certain types of cancer. This review emphasizes the production of oils containing C18 CFAs in the developing seeds of genetically engineered oleaginous plants. Designing effective strategies to increase the accumulation of CFAs in plant species which do not normally produce these FAs requires a detailed knowledge of FA biosynthesis and triacylglycerol assembly in both the species to be engineered and the species that normally produces the CFA. One of the major challenges in engineering oil crops to produce CFAs, and other unusual FAs, is to effectively remove these FAs from phosphatidylcholine and make them available for incorporation into triacylglycerol.