Chen Liming, Zhao Bixi, Zhang Miao, Yan Yuxi, Nie Cailong, Yu Kaiqiang, Tu Zhihao, Xia Yu
School of Environmental Science and Engineering, College of Engineering, Southern University of Science and Technology, Shenzhen 518055, China.
School of Environmental Science and Engineering, College of Engineering, Southern University of Science and Technology, Shenzhen 518055, China; State Environmental Protection Key Laboratory of Integrated Surface Water-Groundwater Pollution Control, School of Environmental Science and Engineering, Southern University of Science and Technology, Shenzhen 518055, China; Guangdong Provincial Key Laboratory of Soil and Groundwater Pollution Control, School of Environmental Science and Engineering, Southern University of Science and Technology, Shenzhen, 518055, China.
Water Res. 2025 Jul 1;279:123419. doi: 10.1016/j.watres.2025.123419. Epub 2025 Mar 1.
Microbial spatial heterogeneity is an important determinant of larger-scale community properties, whereas most studies neglect it and therefore only provide average information, potentially obscuring the signal of microbial interactions. Our study takes a step toward addressing this problem by characterizing the spatial heterogeneity of a microbiome with micron-scale resolution. Micron-scale single clusters (40-70 μm) were randomly collected from lab-scale anaerobic digestion (AD) biosystems, and a comparative analysis was performed to evaluate differences between mesophilic and thermophilic systems. Here we reveal a cascading effect from high-temperature selection to global microbial interactions. We observed that thermophilic communities exhibited less spatial heterogeneity than mesophilic communities, which we attribute to the considerable extinction of low-abundant species by high-temperature selection. Then, the low spatial heterogeneity and the high-temperature selection acting in conjunction resulted in a high proportion of competitive interactions in thermophilic communities. Unexpectedly, however, the thermophilic AD, characterized by lower micron-scale spatial heterogeneity, showed more efficient synergistic and syntrophic cooperations involving around Clostridiales, which significantly enhanced hydrolysis performance under thermophilic conditions. In addition, the fact that high temperatures favor slower growers, along with functional redundancy-related competitive advantage, led to the selection of more proficient methanogens in more competitive environments, which are also potentially associated with enhanced methanogenic performance. In summary, our findings underscore the significance of micron-scale resolution for revealing the microbial ecology in spatially structured environments.
微生物空间异质性是更大尺度群落特性的重要决定因素，然而大多数研究忽略了这一点，因此仅提供平均信息，这可能会掩盖微生物相互作用的信号。我们的研究朝着解决这个问题迈出了一步，通过以微米级分辨率表征微生物组的空间异质性。从实验室规模的厌氧消化（AD）生物系统中随机收集微米级的单个聚集体（40 - 70μm），并进行比较分析以评估中温系统和高温系统之间的差异。在这里，我们揭示了从高温选择到全球微生物相互作用的级联效应。我们观察到，嗜热群落比中温群落表现出更少的空间异质性，我们将其归因于高温选择导致低丰度物种的大量灭绝。然后，低空间异质性和高温选择共同作用，导致嗜热群落中竞争相互作用的比例很高。然而，出乎意料的是，以较低的微米级空间异质性为特征的嗜热AD显示出更多涉及梭菌目的高效协同和互营合作，这在嗜热条件下显著增强了水解性能。此外，高温有利于生长较慢的微生物这一事实，以及与功能冗余相关的竞争优势，导致在竞争更激烈的环境中选择了更高效的产甲烷菌，这也可能与产甲烷性能的增强有关。总之，我们的研究结果强调了微米级分辨率对于揭示空间结构化环境中微生物生态学的重要性。
