Jiao Shuo, Zhang Zhengqing, Yang Fan, Lin Yanbing, Chen Weimin, Wei Gehong
State Key Laboratory of Crop Stress Biology in Arid Areas, College of Life Sciences, Northwest A&F University, Yangling, Shaanxi, 712100, China.
Laboratory of Forestry Pests Biological Control, College of Forestry, Northwest A&F University, Yangling, Shaanxi, 712100, China.
Mol Ecol. 2017 Feb;26(3):923-936. doi: 10.1111/mec.13978. Epub 2017 Jan 31.
Elucidating the mechanisms underlying microbial succession is a major goal of microbial ecology research. Given the increasing human pressure on the environment and natural resources, responses to the repeated introduction of organic and inorganic pollutants are of particular interest. To investigate the temporal dynamics of microbial communities in response to pollutants, we analysed the microbial community structure in batch microcosms that were inoculated with soil bacteria following exposure to individual or combined pollutants (phenanthrene, n-octadecane, phenanthrene + n-octadecane and phenanthrene + n-octadecane + CdCl ). Subculturing was performed at 10-day intervals, followed by high-throughput sequencing of 16S rRNA genes. The dynamics of microbial communities in response to different pollutants alone and in combination displayed similar patterns during enrichment. Specifically, the repression and induction of microbial taxa were dominant, and the fluctuation was not significant. The rate of appearance for new taxa and the temporal turnover within microbial communities were higher than the rates reported in other studies of microbial communities in air, water and soil samples. In addition, conditionally rare taxa that were specific to the treatments exhibited higher betweenness centrality values in the co-occurrence network, indicating a strong influence on other interactions in the community. These results suggest that the repeated introduction of pollutants could accelerate microbial succession in microcosms, resulting in the rapid re-equilibration of microbial communities.
阐明微生物演替的潜在机制是微生物生态学研究的主要目标。鉴于人类对环境和自然资源的压力不断增加，对有机和无机污染物反复引入的响应尤其令人关注。为了研究微生物群落对污染物响应的时间动态，我们分析了在暴露于单一或混合污染物（菲、正十八烷、菲 + 正十八烷以及菲 + 正十八烷 + 氯化镉）后接种土壤细菌的分批微观世界中的微生物群落结构。每隔10天进行一次传代培养，随后对16S rRNA基因进行高通量测序。在富集过程中，微生物群落对不同单一污染物和混合污染物响应的动态呈现出相似的模式。具体而言，微生物类群的抑制和诱导占主导地位，波动不显著。新类群的出现率和微生物群落内部的时间周转率高于其他关于空气、水和土壤样品中微生物群落研究报告的速率。此外，特定于处理的条件性稀有类群在共现网络中表现出较高的中介中心性值，表明对群落中的其他相互作用有强烈影响。这些结果表明，污染物的反复引入可加速微观世界中的微生物演替，导致微生物群落迅速重新平衡。
