Bacteria living on the cuticle of ants are generally studied for their protective role against pathogens, especially in the clade of fungus-growing ants. However, little is known regarding the diversity of cuticular bacteria in other ant host species, as well as the mechanisms leading to the composition of these communities. Here, we used 16S rRNA gene amplicon sequencing to study the influence of host species, species interactions and the pool of bacteria from the environment on the assembly of cuticular bacterial communities on two phylogenetically distant Amazonian ant species that frequently nest together inside the roots system of epiphytic plants, Camponotus femoratus and Crematogaster levior. Our results show that (a) the vast majority of the bacterial community on the cuticle is shared with the nest, suggesting that most bacteria on the cuticle are acquired through environmental acquisition, (b) 5.2% and 2.0% of operational taxonomic units (OTUs) are respectively specific to Ca. femoratus and Cr. levior, probably representing their respective core cuticular bacterial community, and (c) 3.6% of OTUs are shared between the two ant species. Additionally, mass spectrometry metabolomics analysis of metabolites on the cuticle of ants, which excludes the detection of cuticular hydrocarbons produced by the host, were conducted to evaluate correlations among bacterial OTUs and m/z ion mass. Although some positive and negative correlations are found, the cuticular chemical composition was weakly species-specific, suggesting that cuticular bacterial communities are prominently environmentally acquired. Overall, our results suggest the environment is the dominant source of bacteria found on the cuticle of ants.

中文翻译：

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解开共享共同树栖的两个亚马逊蚂蚁物种的蚂蚁表皮细菌群落的组装机制。

通常研究生活在蚂蚁表皮上的细菌对病原体的保护作用，尤其是在真菌生长的蚂蚁进化枝中。然而，关于其他蚂蚁宿主物种中表皮细菌的多样性以及导致这些群落组成的机制知之甚少。在这里，我们使用16S rRNA基因扩增子测序来研究宿主物种，物种相互作用和来自环境的细菌池对两个系统发生距离遥远的亚马逊蚂蚁物种的表皮细菌群落组装的影响，该物种经常嵌套在一起形成根系。附生植物，Camponotus femoratus和Crematogaster levior。我们的结果表明（a）表皮上的绝大多数细菌群落与巢共享，这表明表皮上的大多数细菌是通过环境获取而获得的，（b）5.2％和2.0％的操作分类单位（OTU）分别对Ca具有特异性。股骨和铬。levior，可能代表了它们各自的核心表皮细菌群落，（c）两种蚂蚁物种共享3.6％的OTU。此外，进行了蚂蚁角质层代谢物的质谱代谢组学分析，这不包括检测宿主产生的表皮碳氢化合物，以评估细菌OTU与m / z离子质量之间的相关性。尽管发现了一些正相关和负相关，但表皮化学成分的物种特异性较弱，这表明表皮细菌群落在环境上非常重要。总体，