Biosynthesis of Linoleic Acid in Insects

该提案描述了旨在描述一种小说特征的研究 12昆虫中的脱氢酶。 脊椎动物不能合成， 需要亚油酸的膳食来源，18：2（n-6）， 既作为膜的结构组分，又作为膜的前体， 类花生酸 直到最近，所有的动物，包括昆虫， 被认为不能合成亚油酸。 在我们的研究 实验室证明，一些昆虫物种具有 12去饱和酶，因此能够产生亚油酸。 由NSF资助的广泛研究， 明确地证明了昆虫组织， 微生物，含有12去饱和酶。 建议进行研究 在此为了表征来自三种代表性的12种去饱和酶， 昆虫物种，蟑螂，蟋蟀和蚜虫。 工作将 完成，以阐明底物要求和特异性， 去饱和酶，以优化活性，以确定数量， 去饱和酶中组分的性质，以检查 活动的生理调节，以确定 新合成的亚油酸酯，并开始增溶工作 和酶的纯化。 重要的基础知识 将从这项工作中获得比较脂质代谢。 %%% 所有脊椎动物的重要饮食需求之一， 包括人类，是必需的脂肪酸，亚油酸。 这种脂肪酸是细胞膜所必需的成分， 以及作为其他生理学上的先驱， 重要的化合物，如某些激素。 直到最近，所有 动物被认为不能合成这种脂肪酸， 缺乏一种特殊的酶，12去饱和酶。 但我们 发现许多种昆虫，但不是全部， 这种酶。 因此，操纵这种酶，新的在 昆虫，具有控制昆虫的潜力。 工作 在这个建议中描述的是旨在检查这种酶， 更详细地，比较它在昆虫物种和 在植物中发现的类似酶。 重要的基础知识 将从这项工作中获得比较脂质代谢。

This proposal describes studies designed to characterize a novel 12 desaturase in insects. Vertebrates cannot synthesize and thus require a dietary source of linoleic acid, 18:2(n-6), which is used both as a structural component of membranes and as a precursor for the eicosanoids. Until recently, all animals, including insects, were considered unable to synthesize linoleic acid. Studies in our laboratory demonstrated that a number of insect species possess a 12 desaturase and are thus able to produce linoleic acid. Extensive research, funded by the NSF, was performed to unambiguously demonstrate that insect tissue, and not associated microorganisms, contain the 12 desaturase. Studies are proposed herein to characterize the 12 desaturase from three representative insect species, a cockroach, a cricket and an aphid. Work will be done to elucidate the substrate requirements and specificity for the desaturase, to optimize activity, to determine the number and nature of the components in the desaturase, to examine the physiological regulation of activity, to determine the fate of the newly synthesized linoleate and to begin work on the solubilization and purification of the enzyme. Significant fundamental knowledge of comparative lipid metabolism will be obtained from this work. %%% One of the important dietary requirements in all vertebrates, including humans, is the essentials fatty acid, linoleic acid. This fatty acid is required as a component of cell membranes as well as functioning as a precursor for other physiologically important compounds such as certain hormones. Until recently, all animals were considered unable to synthesize this fatty acid due to the absence of a specific enzyme, the 12 desaturase. However, we have discovered that many, but not all, species of insects possess this enzyme. Therefore, manipulation of this enzyme, novel in insects, holds the potential for insect control. The work described in this proposal is designed to examine this enzyme in greater detail, to compare it across insect species and to the similiar enzyme found in plants. Significant fundamental knowledge of comparative lipid metabolism will be obtained from this work.