Figure 7.

Hypothesized polyketide synthase (PKS) pathways in A. minutum to synthesize 20:5n-3 and 22:6n-3. Numbers in boxes correspond to the final AE value (at t₅₄), white corresponds to neutral lipids and black to polar lipids. The PKS intermediates written in grey are not detected during the study, as the enzyme proteins might not release them until the final product is synthesized [19]. The circles represent the enzymes involved in these pathways: KS: 3-ketoacyl synthase; KR: 3-ketoacyl-ACP-reductase; DH: dehydrase; 2.2I/2.3I: 2-trans, 2-cis, or 2-trans, 3-cis isomerase; ER: enoyl-reductase. The numbers at the top of each pathways represent the suspected order of 20:5n-3 and 22:6n-3 synthesis according to the ¹³C-enrichment dynamics observed in this study.