Comparative ascaroside profiling of Caenorhabditis nematodes using HPLC-ESI-(−)-MS/MS precursor ion scanning revealed a class of highly species-specific ascaroside dimers. Their 2- and 4-isomeric, homo- and heterodimeric structures were identified using a combination of HPLC-ESI-(+)-HR-MS/MS spectrometry and high-resolution dqf-COSY NMR spectroscopy. Structure assignments were confirmed by total synthesis of representative examples. Functional characterization using holding assays indicated that males of Caenorhabditis remanei and Caenorhabditis nigoni are exclusively retained by their conspecific ascaroside dimers, demonstrating that dimerization of conserved monomeric building blocks represents a yet undescribed mechanism that generates species-specific signaling molecules in the Caenorhabditis genus.

中文翻译：

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保守蛔苷构建块的二聚化在 Caenorhabditis 线虫中产生物种特异性雄性引诱剂。

使用 HPLC-ESI-(-)-MS/MS 前体离子扫描对Caenorhabditis线虫进行的蛔苷比较分析揭示了一类高度物种特异性的蛔苷二聚体。使用 HPLC-ESI-(+)-HR-MS/MS 光谱和高分辨率dqf - COSY NMR 光谱的组合鉴定了它们的 2-和 4-异构体、同源和异源二聚体结构。通过代表性实例的全合成确认结构分配。使用存储功能的测定表明表征的，男性线虫remanei和线虫nigoni仅由它们的同种蛔苷二聚体保留，表明保守单体构建块的二聚化代表了一种尚未描述的机制，该机制在Caenorhabditis属中产生物种特异性信号分子。