In recent years, bacteria of the genus Massilia have been identified as promising sources of bioactive natural products. In this study, we used mass spectrometry (MS)‐based molecular networking for the first comprehensive analysis of the secondary metabolome of these microorganisms. Annotation of the detected metabolite clusters with a mass fragmentation database revealed several compounds not previously known to be produced by Massilia species. To secure sufficient material for further structural analyses as well as biological testing, we selected the most promising producer strains from our molecular networking analysis and subjected them to larger‐scale cultivation. Following extraction and UV‐directed isolation, we obtained five metabolites in milligram quantities. In addition to a cyclic dipeptide, we elucidated the structures of four acyl amino acids that are related to thalassotalic acid C from the marine bacterium Thalassotalea sp. The Massilia‐derived kyonggic acids were found to inhibit the enzyme tyrosinase, which is involved in melanin biosynthesis influencing skin and hair pigmentation. This study illustrates the value of combining spectroscopic and computational tools in natural product discovery in order to detect and guide the isolation of previously overlooked bioactive compounds.

中文翻译：

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分子网络引导马西利亚属中 Kyonggic 酸的发现。

近年来，Massilia 属细菌已被确定为生物活性天然产物的有前途的来源。在这项研究中，我们使用基于质谱（MS）的分子网络对这些微生物的次级代谢组进行了首次全面分析。使用质量碎片数据库对检测到的代谢物簇进行注释，揭示了几种以前未知的马西利亚物种产生的化合物。为了确保有足够的材料进行进一步的结构分析和生物测试，我们从分子网络分析中选择了最有前途的生产菌株，并对它们进行了大规模培养。经过提取和紫外引导分离后，我们获得了五种毫克级的代谢物。除了环状二肽之外，我们还阐明了与海洋细菌 Thalassotalea sp. 的海藻酸 C 相关的四种酰基氨基酸的结构。研究发现，源自 Massilia 的 kyonggic 酸可以抑制酪氨酸酶，该酶参与影响皮肤和头发色素沉着的黑色素生物合成。这项研究说明了在天然产物发现中结合光谱和计算工具的价值，以检测和指导以前被忽视的生物活性化合物的分离。