Huo Tangran, Zhao Yunpeng, Tang Xi, Zhao Huazhang, Ni Shouqing, Gao Qiang, Liu Sitong
Department of Environmental Sciences and Engineering, Peking University, Beijing 100871, China.
State Key Laboratory of Plateau Ecology and Agriculture, Qinghai University, Xining 810016, Qinghai, China.
Environ Int. 2020 Oct;143:105915. doi: 10.1016/j.envint.2020.105915. Epub 2020 Jul 8.
Widespread application of anammox process has been primarily limited to the high sensitivity of anammox consortia to fluctuations of temperature. However, the metabolic acclimation of anammox consortia to decreased temperature remains unclear, which is the core of developing potential strategies for improving their low-temperature resistance. Here, we operated anammox reactors at 25 °C and 35 °C to explore the acclimation mechanism of anammox consortia in terms of metabolic responses and cross-feedings. Accordingly, we found that the adaptation of anammox consortia to ambient temperature (25 °C) was significantly linked to energy conservation strategy, resulting in decreased extracellular polymeric substance secretion, accumulation of ATP and amino acids. The expression patterns of cold shock proteins and core enzymes caused the apparent metabolic advantage of Candidatus Brocadia fulgida for acclimation to ambient temperature compared to other anammox species. Importantly, strengthened cross-feedings of amino acids, nitrite and glycine betaine benefited adaptation of anammox consortia to ambient temperature. Our work not only uncovers the temperature-adaptive mechanisms of anammox consortia, but also emphasizes the important role of metabolic cross-feeding in the temperature adaptation of microbial community.
厌氧氨氧化工艺的广泛应用主要受限於厌氧氨氧化菌对温度波动的高敏感性。然而，厌氧氨氧化菌对温度降低的代谢适应性仍不清楚，这是制定提高其低温抗性潜在策略的核心。在此，我们在25℃和35℃下运行厌氧氨氧化反应器，从代谢反应和交叉喂养方面探索厌氧氨氧化菌的适应机制。据此，我们发现厌氧氨氧化菌对环境温度（25℃）的适应与能量守恒策略显著相关，导致细胞外聚合物分泌减少、ATP和氨基酸积累。与其他厌氧氨氧化菌相比，冷休克蛋白和核心酶的表达模式导致了富亮除碳菌在适应环境温度方面具有明显的代谢优势。重要的是，氨基酸、亚硝酸盐和甘氨酸甜菜碱的强化交叉喂养有利于厌氧氨氧化菌对环境温度的适应。我们的工作不仅揭示了厌氧氨氧化菌的温度适应机制，还强调了代谢交叉喂养在微生物群落温度适应中的重要作用。
