Department of Environmental Systems Science, ETH Zürich, 8092, Zürich, Switzerland.
Department of Environmental Microbiology, Swiss Federal Institute of Aquatic Science and Technology (Eawag), 8600, Dübendorf, Switzerland.
Environ Microbiol. 2018 Dec;20(12):4356-4368. doi: 10.1111/1462-2920.14352. Epub 2018 Aug 7.
Biological richness is positively associated with the rates of some metabolic processes performed by microbial communities. It remains unclear, however, whether these positive associations are a general feature of the metabolic processes performed by microbial communities or whether they are specific to certain types of metabolic processes. For example, it was hypothesized that the strength of any particular positive association depends on how many different genotypes within a microbial community perform the metabolic process of interest (i.e. the 'rarity hypothesis'). We tested the generality of these positive associations by measuring the taxonomic richness, functional gene richness and rate constants for 71 different metabolic processes across 30 independent microbial communities. We found that both taxonomic and functional gene richness do indeed tend to positively associate with the rates of metabolic processes. In addition, we found that positive associations occur across a wide range of different environmental conditions. Counter to the 'rarity hypothesis', however, we did not detect a relationship between the strengths of the positive associations and the rarity of each metabolic process. Together, our data provide empirical evidence that positive associations with biological richness may indeed be a general feature of the metabolic processes performed by microbial communities.
生物丰富度与微生物群落进行的某些代谢过程的速率呈正相关。然而，目前尚不清楚这些正相关是否是微生物群落进行的代谢过程的一般特征，还是仅特定于某些类型的代谢过程。例如，有人假设，任何特定正相关的强度取决于微生物群落中执行感兴趣的代谢过程的不同基因型的数量（即“稀有性假说”）。我们通过测量 30 个独立微生物群落中 71 种不同代谢过程的分类丰富度、功能基因丰富度和速率常数，来检验这些正相关的普遍性。我们发现，分类和功能基因丰富度确实与代谢过程的速率呈正相关。此外，我们还发现，正相关在广泛的不同环境条件下发生。然而，与“稀有性假说”相反，我们没有检测到正相关强度与每种代谢过程的稀有性之间的关系。总的来说，我们的数据提供了经验证据，表明与生物丰富度的正相关可能确实是微生物群落进行的代谢过程的一般特征。
