Two Co-Expression Strategies for Eicosapentaenoic Acid Production in Mortierella alpina

Abstract

The omega-3 long-chain Polyunsaturated Fatty Acid (PUFA) Eicosapentaenoic Acid (EPA) has beneficial effects on human health, leading to its use in health products and foods. The oleaginous microorganism Mortierella alpina has been used in the industrial production of Arachidonic Acid (AA). The omega-3 desaturase oPpFADS17 is a key enzyme in the bioconversion of AA to EPA from Phytophthora parasitica and Glucose-6-Phosphate Dehydrogenase (G6PD2) is a critical enzyme that provide reducing power NADPH for lipid biosynthesis. In this study, we used a double expression cassette and 2A peptide strategies to co-express the these two critical enzymes. Subsequently, we investigated the effects of these strategies on total lipid and EPA accumulation. The recombination strains generated using the above-described strategies exhibited no differences in cell growth, compared with the control strain. Recombination strains generated using the double expression cassette exhibited an increase in total lipids to 43% of the cell dry weight, but did not accumulate EPA. Recombination strains generated using the 2A peptide strategy exhibited increased EPA accumulation, such that this PUFA accounted for 30% of the total lipid content. These co-expression strategies provide the improvements of multigene modification in PUFA accumulation in M. alpina.

Modular Metabolic Engineering of Mortierella alpina by the 2A Peptide Platform to Improve Arachidonic Acid Production

“…Previous studies used a 2A peptide that did not contain the typical cleavage sequence (-DxExNPGP-), resulting in a relatively low shear efficiency. The expression of ω-3 desaturase (oPpFADS17) and glucose-6-phosphate dehydrogenase (G6PD2) with this 2A peptide was ineffective . The 2A peptide sequence used in this study contained a typical -DxExNPGP- cleavage site that significantly improved the cleavage efficiency.…”

“…The expression of ω-3 desaturase (oPpFADS17) and glucose-6-phosphate dehydrogenase (G6PD2) with this 2A peptide was ineffective. 30 The 2A peptide sequence used in this study contained a typical -DxExNPGP-cleavage site that significantly improved the cleavage efficiency. The cleavage efficiency of 2A used in this study was approximately 100%, as determined by Western blot analysis.…”