Institut de Chimie des Substances Naturelles , CNRS UPR 2301, Univ. Paris-Sud, Université Paris-Saclay , Avenue de la Terrasse , 91198 Gif-sur-Yvette , France.
Institut de Physique Nucléaire , UMR 8608, IN2P3-CNRS, Université Paris-Sud, Université Paris-Saclay , 91406 Orsay , France.
Anal Chem. 2018 Jun 19;90(12):7535-7543. doi: 10.1021/acs.analchem.8b01157. Epub 2018 Jun 8.
Driven by a necessity for confident molecular identification at high spatial resolution, a new time-of-flight secondary ion mass spectrometry (TOF-SIMS) tandem mass spectrometry (tandem MS) imaging instrument has been recently developed. In this paper, the superior MS/MS spectrometry and imaging capability of this new tool is shown for natural product study. For the first time, via in situ analysis of the bioactive metabolites rubrynolide and rubrenolide in Amazonian tree species Sextonia rubra (Lauraceae), we were able both to analyze and to image by tandem MS the molecular products of natural biosynthesis. Despite the low abundance of the metabolites in the wood sample(s), efficient MS/MS analysis of these γ-lactone compounds was achieved, providing high confidence in the identification and localization. In addition, tandem MS imaging minimized the mass interferences and revealed specific localization of these metabolites primarily in the ray parenchyma cells but also in certain oil cells and, further, revealed the presence of previously unidentified γ-lactone, paving the way for future studies in biosynthesis.
受在高空间分辨率下进行可靠分子鉴定的需求驱动，最近开发了一种新型飞行时间二次离子质谱（TOF-SIMS）串联质谱（tandem MS）成像仪器。本文展示了该新工具在天然产物研究中的优越的 MS/MS 光谱和成像能力。通过对亚马逊树种 Sextonia rubra（樟科）中生物活性代谢物rubrynolide 和 rubrenolide 的原位分析，我们首次能够通过串联 MS 分析和成像天然生物合成的分子产物。尽管木材样品中代谢物的丰度较低，但仍能对这些γ-内酯化合物进行有效的 MS/MS 分析，从而提供了在鉴定和定位方面的高度置信度。此外，串联 MS 成像最大限度地减少了质量干扰，并显示了这些代谢物主要在射线薄壁细胞中以及某些油细胞中的特定定位，进一步揭示了以前未被识别的γ-内酯的存在，为未来的生物合成研究铺平了道路。
