Institute of Zoology, University of Regensburg, Regensburg, Germany.
Arch Insect Biochem Physiol. 2021 Jun;107(2):e21788. doi: 10.1002/arch.21788. Epub 2021 Apr 4.
Linoleic acid (C18:2 , LA) is an important metabolite with numerous essential functions for growth, health, and reproduction of organisms. It has long been assumed that animals lack ∆12-desaturases, the enzymes needed to produce LA from oleic acid (C18:1 , OA). There is, however, increasing evidence that this is not generally true for invertebrates. In the insect order Hymenoptera, LA biosynthesis has been shown for only two parasitic wasp species of the so-called "Nasonia group," but it is unknown whether members of other taxa are also capable of synthesizing LA. Here, we demonstrate LA biosynthesis in 13 out of 14 species from six families of parasitic wasps by gas chromatography-mass spectrometry analysis using two different stable isotope labeling techniques. Females of the studied species converted topically applied fully C-labeled OA into LA and/or produced labeled LA after feeding on fully C-labeled α- d-glucose. These results indicate that ∆12-desaturases are widespread in parasitic Hymenoptera and confirm previous studies demonstrating that these insects are capable of synthesizing fatty acids de novo.
亚油酸（C18:2，LA）是一种重要的代谢物，对于生物体的生长、健康和繁殖具有众多必需功能。长期以来，人们一直认为动物缺乏 ∆12-去饱和酶，而这种酶是将油酸（C18:1，OA）转化为 LA 所必需的。然而，越来越多的证据表明，这对于无脊椎动物来说并不普遍。在昆虫目膜翅目，仅在所谓的“纳索尼亚组”的两种寄生性黄蜂物种中已经证明了 LA 的生物合成，但尚不清楚其他分类群的成员是否也能够合成 LA。在这里，我们通过使用两种不同的稳定同位素标记技术的气相色谱-质谱分析，证明了来自寄生黄蜂六个科的 14 个物种中的 13 个能够进行 LA 生物合成。研究物种的雌性通过将局部应用的完全 C 标记的 OA 转化为 LA 和/或在用完全 C 标记的 α-d-葡萄糖喂养后产生标记的 LA，从而进行 LA 生物合成。这些结果表明，∆12-去饱和酶在寄生性膜翅目昆虫中广泛存在，并证实了先前的研究表明这些昆虫能够从头合成脂肪酸。
