Microbial Ecology Laboratory, Microbiology, School of Natural Sciences and Ryan Institute, National University of Ireland, Galway, Ireland.
Microb Biotechnol. 2012 Nov;5(6):738-52. doi: 10.1111/j.1751-7915.2012.00364.x. Epub 2012 Sep 11.
Methanogenic community structure and dynamics were investigated in two different, replicated anaerobic wastewater treatment reactor configurations [inverted fluidized bed (IFB) and expanded granular sludge bed (EGSB)] treating synthetic dairy wastewater, during operating temperature transitions from 37°C to 25°C, and from 25°C to 15°C, over a 430-day trial. Non-metric multidimensional scaling (NMS) and moving-window analyses, based on quantitative real-time PCR data, along with denaturing gradient gel electrophoresis (DGGE) profiling, demonstrated that the methanogenic communities developed in a different manner in these reactor configurations. A comparable level of performance was recorded for both systems at 37°C and 25°C, but a more dynamic and diverse microbial community in the IFB reactors supported better stability and adaptative capacity towards low temperature operation. The emergence and maintenance of particular bacterial genotypes (phylum Firmicutes and Bacteroidetes) was associated with efficient protein hydrolysis in the IFB, while protein hydrolysis was inefficient in the EGSB. A significant community shift from a Methanobacteriales and Methanosaetaceae towards a Methanomicrobiales-predominated community was demonstrated during operation at 15°C in both reactor configurations.
采用两种不同的厌氧废水处理反应器构型（倒置流化床[IFB]和膨胀颗粒污泥床[EGSB]）处理合成乳制品废水，研究了甲烷菌群落结构和动态变化，在 430 天的试验中，操作温度从 37°C 分别过渡到 25°C 和 15°C。基于定量实时 PCR 数据的非度量多维尺度分析（NMS）和移动窗口分析，以及变性梯度凝胶电泳（DGGE）分析表明，甲烷菌群落以不同的方式在这两种反应器构型中发展。这两个系统在 37°C 和 25°C 时的性能相当，但 IFB 反应器中更具动态性和多样性的微生物群落支持其在低温运行时具有更好的稳定性和适应能力。在 IFB 中，特定细菌基因型（厚壁菌门和拟杆菌门）的出现和维持与有效的蛋白质水解有关，而在 EGSB 中，蛋白质水解效率较低。在两个反应器构型中，在 15°C 运行时，从 Methanobacteriales 和 Methanosaetaceae 为主的群落演变为以 Methanomicrobiales 为主的群落。
