Production of eicosapentaenoic acid by a recombinant marine cyanobacterium, Synechococcus sp

The eicosapentaenoic acid (EPA) synthesis gene cluster from an EPA-producing bacterium, Shewanella sp. SCRC-2738, was cloned into a broad-host range vector, pJRD215, and then introduced into a marine cyanobacterium, Synechococcus sp. NKBG15041c, by conjugation. The transconjugant cyanobacteria produced 3.7 ± 0.2% (2.24 ± 0.13 mg/L) EPA (n-3) and 2.5 ± 0.2% (1.49 ± 0.06 mg/L) eicosatetraenoic acid (n-3) of the total fatty acids when the cells were cultured at 23°C at a light intensity of 1,000-1,500 Lux. The EPA and eico-satetraenoic acid contents of the cells were increased to 4.6 ± 0.6% (3.86 ± 1.11 mg/L) and 4.7 ± 0.3% (3.86 ± 0.82 mg/L), and 7.5 ± 0.3% (1.76 ± 0.10 mg/L) and 5.1 ± 0.2% (1.19 ± 0.06 mg/L) when they were cultured at low temperature (18°C) and at lower light intensity (40 Lux), respectively.