Arthropods produce a great variety of natural compounds, many of which have unexplored biosynthesis. Among the armored harvestmen (Arachnida: Opiliones) of the suborder Laniatores, the defensive gland exudates contain vinyl ketones and other constituents of supposed polyketide origin. We have studied the biosynthesis of 1-hepten-3-one in the Neotropical harvestman Iporangaia pustulosa by feeding individuals with ¹³C-labeled precursors, demonstrating its mixed acetate/propionate origin. ¹³C NMR spectroscopy showed an unusual labeling pattern suggesting different propionate sources for starting and extender units. Our analysis also indicates the presence of methylmalonyl-CoA mutase, converting acetate into propionyl-CoA via succinyl-CoA, together with other C₃ unit routes. This is the first biosynthetic study of alkyl vinyl ketones in arthropods. Our results shed light on the origin and diversification of chemical compounds in a major arthropod group.

中文翻译：

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Iporangaia pustulosa (Opiliones) 中 1-hepten-3-one 的第一个生物合成途径。


节肢动物产生多种天然化合物，其中许多具有未经探索的生物合成。在羊毛亚目的装甲收割者（蛛形纲：Opiliones）中，防御性腺体分泌物含有乙烯基酮和其他假定的聚酮化合物来源的成分。我们通过给个体喂食 13 C 标记的前体，研究了新热带收割者 Iporangaia pustulosa 中 1-庚烯-3-酮的生物合成，证明了其混合乙酸/丙酸来源。 13C NMR 光谱显示出不寻常的标记模式，表明起始单元和增量单元的丙酸盐来源不同。我们的分析还表明存在甲基丙二酰辅酶A变位酶，通过琥珀酰辅酶A以及其他C₃单元途径将乙酸盐转化为丙酰辅酶A。这是节肢动物中烷基乙烯基酮的首次生物合成研究。我们的结果揭示了主要节肢动物群中化合物的起源和多样化。