We present a method for the physical isolation of endospores from environmental samples allowing the specific targeting of endospore‐forming bacteria for sequencing (endospore‐enriched community). The efficiency of the method was tested on lake sediment samples. After 16S rRNA gene amplicon sequencing, the composition in the endospore‐enriched community was compared with the community from untreated control samples (whole community). In the whole community, Firmicutes had a relative abundance of 8% and 19% in the two different lake sediments. In contrast, in the endospore‐enriched community, Firmicutes abundance increased to 90.6% and 83.9%, respectively, confirming the efficiency of the endospore enrichment. The relative abundance of other microbial groups that form spore‐like resisting states (i.e. actinobacteria, cyanobacteria and myxococcales) was below 2% in the endospore‐enriched community, indicating that the method is adapted to true endospores. Representatives from two out of the three known classes of Firmicutes (Bacilli and Clostridia) were detected and supposedly asporogenic groups (e.g. Ethanoligenes and Trichococcus) could be detected. The method presented here is a leap forward for ecological studies of endospore‐forming Firmicutes. It can be applied to other types of samples in order to reveal the diversity and metabolic potential of this bacterial group in the environment.

中文翻译：

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富集内生孢子的测序方法揭示了沉积物中前所未有的菌丝多样性。

我们提出了一种从环境样品中物理分离出内生孢子的方法，该方法可对内生孢子形成细菌进行特异性靶向以进行测序（内生孢子丰富的群落）。在湖沉积物样品上测试了该方法的效率。在对16S rRNA基因扩增子进行测序后，将富含内生孢子的群落与未经处理的对照样品（整个群落）的群落进行了比较。在整个社区中，沙丁鱼在两种不同的湖泊沉积物中的相对丰度分别为8％和19％。相反，在富含内生孢子的群落中，Firmicutes丰度分别增加到90.6％和83.9％，证实了内生孢子富集的效率。在富含内生孢子的群落中，其他形成孢子样抵抗状态的微生物群（例如放线菌，蓝细菌和粘球菌）的相对丰度低于2％，表明该方法适用于真正的内生孢子。从两个代表出了三种已知类别的硬壁菌（芽孢杆菌和梭状芽胞杆菌进行检测），也应该无孢子团（例如Ë thanoligenes和Ť richococcus可检测）。此处介绍的方法是对形成内生孢子的菌毛进行生态学研究的一个飞跃。可以将其应用于其他类型的样品，以揭示环境中该细菌群的多样性和代谢潜力。