Identification and characterization of a novel Δ4-fatty acid desaturase (Bm4DES) to engineer high yield of very long-chain polyunsaturated fatty acids

Abstract

Docosahexaenoic acid (DHA 22:6n-3) are significant product in biosynthetic pathway for the very-long-chain poly unsaturated fatty acids. To develop a sustainable system for the production of dietary polyunsaturated fatty acids, we focused the action of the key enzyme novel delta 4-desaturase (BmD4DES) on Docosapentaenoic acid (DPA 22:5n-3). A963-bp full-length cDNA encoding D4DES (BmD4DES) was cloned from Berryteuthis magister using PCR and RNA sequencing method (analyzed for Octupus vulgaris genome as reference). To investigate the enzymatic activity of BmD4DES in production of DHA, A recombinant plasmid expressing BmD4DES (pYES-BmD4DES) was transformed into and expressed in Saccharomyces cerevisiae. The exogenous expressed BmD4DES produced DHA at conversion rate of 61.98 % from exogenous DPA sustrates. This result indicate the possibility of the de novo production of ω3 long chain polyunsaturated fatty acids such as docosahexaenoic acid (DHA), important in both aquaculture and human nutrition. Significant amounts of plant-derived ω3 “fish oils” can be produce to replace or augment those being sourced from the oceans. The delta 4-desaturase exogenouly supplied substrate22:5(n-3), resulting production of DHA. This is a breakthrough in the development of sustainable alternative sources of DHA as this technology should be applicable in oilseed crop. Production of DHA in plant seed oil has been pursed to improve availability of omega 3 fatty acids that provide important human health benefits. This result support the notion that DHA can be synthesized via