A multidisciplinary approach was carried out in order to study the biodeterioration and the associated microbiome of a XVIII Century wax seal coloured with minium. A small wax seal fragment was observed by scanning electron microscopy combined with energy dispersive spectroscopy in non‐destructive mode. The same object was analysed by Raman and Fourier‐transform infrared spectroscopy. The identification of the microbiota growing on the seal was performed with both a culture‐dependent strategy, combined with hydrolytic assays, and high‐throughput sequencing using the MinION platform. The whole bacterial 16S rRNA gene and the fungal markers ITS and 28S rRNA were targeted. It was observed that the carnauba wax coloured with lead tetroxide (minium) was covered by a biofilm consisting of a network of filaments and other structures of microbial origin. The culture‐dependent and culture‐independent investigations showed the presence of a complex microbiota composed mainly by fungal members, which demonstrated interesting properties related to lipids and lead processing. The formation of lead soaps and secondary biogenic minerals was also described.

中文翻译：

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XVIII世纪蜡封中铅皂的形成和生物多样性，着色最小

进行了多学科的研究，以研究XVIII Century蜡封最少着色的生物降解和相关的微生物组。在无损模式下，通过扫描电子显微镜结合能量色散光谱观察到一个小的蜡封碎片。通过拉曼光谱和傅立叶变换红外光谱法分析了同一物体。使用依赖于培养物的策略，结合水解测定法以及使用MinION平台进行的高通量测序，对在密封上生长的微生物群进行了鉴定。整个细菌的16S rRNA基因和真菌标记ITS和28S rRNA的目标。观察到，用四氧化铅（最小）着色的巴西棕榈蜡被生物膜覆盖，该生物膜由细丝网络和其他微生物来源的结构组成。依赖于培养物和不依赖于培养物的研究表明存在主要由真菌成员组成的复杂微生物群，这表明与脂质和铅加工有关的有趣特性。还描述了铅皂和次生生物矿物的形成。