State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-products, Ningbo University, Ningbo, 315211, China.
School of Marine Sciences, Ningbo University, Ningbo, 315211, China.
Microb Ecol. 2020 Nov;80(4):935-945. doi: 10.1007/s00248-020-01533-6. Epub 2020 Jun 3.
Understanding the rules that govern the successions of gut microbiota is prerequisite for testing general ecological theories and sustaining a desirable microbiota. However, the ignorance of microeukaryotes raises the question of whether gut microeukaryotes are assembled according to the same rules as bacteria. We tracked the shrimp gut bacterial and microeukaryotic communities by a longitudinal dense sampling. The successions of both domains were significantly correlated with host age, with relatively stable microeukaryotic communities in adult shrimp. Gut microeukaryotes exhibited significantly higher turnover rate, but fewer transient species, lower proportion of temporal generalists, and narrower habitat niche breadth than bacteria. The γ-diversity partitioning analysis revealed that the successions of gut microbiotas were primarily ascribed to the high dissimilarity as shrimp aged ([Formula: see text]), whereas the relative importance of [Formula: see text] was significantly higher for microeukaryotes than that for bacteria. Compared with contrasting ecological processes in governing free-living bacteria and microeukaryotes, the ecological patterns were comparable between host-associated gut counterparts. However, the gut microeukaryotes were governed more strongly by deterministic selection relative to nestedness compared with the gut bacteria, which supports the "size-plasticity" hypothesis. Our results highlight the importance of independently interpreting free-living and host-associated meta-communities for a comprehensive understanding of the processes that govern microbial successions.
了解肠道微生物群落演替的规律是检验一般生态理论和维持理想微生物群落的前提。然而，由于对微型真核生物的忽视，人们不禁要问肠道微型真核生物是否是按照与细菌相同的规律组装的。我们通过纵向密集采样跟踪了虾的肠道细菌和微型真核生物群落。两个领域的演替都与宿主年龄显著相关，成年虾的微型真核生物群落相对稳定。肠道微型真核生物的周转率显著较高，但瞬态物种较少，时间性广义种的比例较低，栖息地生态位宽度较窄。γ-多样性划分分析表明，随着虾龄的增长，肠道微生物群落的演替主要归因于高度的不相似性([Formula: see text])，而对于微型真核生物而言，[Formula: see text]的相对重要性明显高于细菌。与自由生活细菌和微型真核生物的对比表明，尽管在控制过程中存在差异，但宿主相关的肠道对应物之间的生态模式具有可比性。然而，与肠道细菌相比，肠道微型真核生物受到确定性选择的影响更强，而嵌套性的影响较弱，这支持了“大小可塑性”假说。我们的研究结果强调了独立解释自由生活和宿主相关元群落对于全面理解控制微生物演替的过程的重要性。
