Background Dietary omega-3 (n-3), long chain (LC-, ≥ 20 carbons), polyunsaturated fatty acids (PUFAs) derived largely from marine animal sources protect against inflammatory processes and enhance brain development and function. With the depletion of natural stocks of marine animal sources and an increasing demand for n-3 LC-PUFAs, alternative, sustainable supplies are urgently needed. As a result, n-3 18-carbon and LC-PUFAs are being generated from plant or algal sources, either by engineering new biosynthetic pathways or by augmenting existing systems. Results We utilized an engineered plasmid encoding two cyanobacterial acyl-lipid desaturases (DesB and DesD, encoding Δ15 and Δ6 desaturases, respectively) and "vesicle-inducing protein in plastids" (Vipp1) to induce production of stearidonic acid (SDA, 18:4 n-3) at high levels in three strains of cyanobacteria (10, 17 and 27% of total lipids in Anabaena sp. PCC7120, Synechococcus sp. PCC7002, and Leptolyngbya sp. strain BL0902, respectively). Lipidomic analysis revealed that in addition to SDA, the rare anti-inflammatory n-3 LC-PUFA eicosatetraenoic acid (ETA, 20:4 n-3) was synthesized in these engineered strains, and ~ 99% of SDA and ETA was complexed to bioavailable monogalactosyldiacylglycerol (MGDG) and digalactosyldiacylglycerol (DGDG) species. Importantly, novel molecular species containing alpha-linolenic acid (ALA), SDA and/or ETA in both acyl positions of MGDG and DGDG were observed in the engineered Leptolyngbya and Synechococcus strains, suggesting that these could provide a rich source of anti-inflammatory molecules. Conclusions Overall, this technology utilizes solar energy, consumes carbon dioxide, and produces large amounts of nutritionally important n-3 PUFAs and LC-PUFAs. Importantly, it can generate previously undescribed, highly bioavailable, anti-inflammatory galactosyl lipids. This technology could therefore be transformative in protecting ocean fisheries and augmenting the nutritional quality of human and animal food products.

中文翻译：

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酰基脂质去饱和酶和 Vipp1 在蓝藻中合作产生新型含 omega-3 多不饱和脂肪酸的糖脂。

背景 膳食 omega-3 (n-3)、长链（LC-，≥ 20 个碳原子）、多不饱和脂肪酸 (PUFA) 主要来源于海洋动物来源，可防止炎症过程并增强大脑发育和功能。随着海洋动物源自然资源的枯竭和对 n-3 LC-PUFA 的需求不断增加，迫切需要替代的、可持续的供应。因此，n-3 18-碳和 LC-PUFA 正在从植物或藻类中产生，要么通过设计新的生物合成途径，要么通过增强现有系统。结果我们利用编码两种蓝藻酰基脂质去饱和酶（DesB 和 DesD，分别编码 Δ15 和 Δ6 去饱和酶）和“质体中的囊泡诱导蛋白”(Vipp1) 的工程质粒来诱导十八碳四烯酸 (SDA, 18: 4 n-3) 在三种蓝藻菌株中处于高水平（分别占鱼腥藻 PCC7120、聚球藻 PCC7002 和 Leptolyngbya 菌株 BL0902 总脂质的 10%、17% 和 27%）。脂质组学分析表明，除了 SDA 外，稀有的抗炎 n-3 LC-PUFA 二十碳四烯酸（ETA，20:4 n-3）在这些工程菌株中合成，约 99% 的 SDA 和 ETA 复合到生物可利用的单半乳糖基二酰基甘油 (MGDG) 和双半乳糖基二酰基甘油 (DGDG) 物种。重要的是，在工程化的 Leptolyngbya 和 Synechococcus 菌株中观察到在 MGDG 和 DGDG 的两个酰基位置都含有 α-亚麻酸 (ALA)、SDA 和/或 ETA 的新型分子种类，这表明它们可以提供丰富的抗炎分子来源. 结论 总的来说，这项技术利用太阳能，消耗二氧化碳，并产生大量具有重要营养意义的 n-3 PUFA 和 LC-PUFA。重要的是，它可以产生以前未描述的、具有高生物利用度的抗炎半乳糖脂质。因此，这项技术可以在保护海洋渔业和提高人类和动物食品的营养质量方面产生变革。