Department of Biology, University of Virginia, Charlottesville, VA 22904-4328, USA.
FEMS Microbiol Ecol. 2012 Sep;81(3):574-82. doi: 10.1111/j.1574-6941.2012.01387.x. Epub 2012 May 23.
Bacteria comprise an essential element of all ecosystems, including those present on and within the human body. Understanding bacterial diversity therefore offers enormous scientific and medical benefit, but significant questions remain regarding how best to characterize that diversity and organize it into biologically meaningful units. Bacterial communities are routinely characterized based on the relative abundances of taxa at the genus or even the phylum level, but the ecological coherence of these high-level taxonomic units is uncertain. Using human microbiota from the skin and gut as our model systems, we tested the ecological coherence of bacteria by investigating the habitat associations of bacteria at all levels of the taxonomic hierarchy. We observed four distinct taxonomic patterns of habitat association, reflecting different levels of ecological coherence among taxa. Our results support the hypothesis that deep-branch bacterial clades could be ecologically coherent and suggest that the phylogenetic depth of ecological coherence varies among the bacterial lineages and is an important factor to consider in studies of human microbiome associations.
细菌是所有生态系统的重要组成部分，包括存在于人体表面和内部的生态系统。因此，了解细菌的多样性具有巨大的科学和医学价值，但关于如何最好地描述这种多样性并将其组织成具有生物学意义的单位，仍存在许多问题。细菌群落通常基于属甚至门水平的分类群的相对丰度来进行特征描述，但这些高级分类单元的生态一致性是不确定的。我们使用皮肤和肠道的人类微生物组作为我们的模型系统，通过研究分类层次结构中所有水平的细菌的栖息地关联来测试细菌的生态一致性。我们观察到了四种不同的栖息地关联的分类模式，反映了分类群之间不同程度的生态一致性。我们的研究结果支持了细菌深支系可能具有生态一致性的假设，并表明生态一致性的系统发育深度在细菌谱系之间存在差异，并且是人类微生物组关联研究中需要考虑的一个重要因素。
