Erdal Ufuk G, Erdal Zeynep K, Daigger Glen T, Randall Clifford W
CH2M HILL, Santa Ana, CA, USA.
Water Sci Technol. 2008;58(6):1329-34. doi: 10.2166/wst.2008.734.
Reduced EBPR performance in full and bench-scale EBPR studies was linked to the proliferation of GAOs but often time with the lack of any evidence. In this study, a detailed enzymatic study was coupled with batch tests and electron microscopy results for a realistic explanation. The results eliminated the possibility of population shift from PAO to GAO or other non-PAO due to the short batch test period provided which would not allow a population shift and further justified with the electron microscopy results. The results indicate that glycogen serves not only as source of reducing power for PHA production but also serves as an alternative energy source when the poly-P pool of the PAOs is depleted. Slow generation of ATP via glycolytic pathway at 5 degrees C cannot satisfy energy requirements of EBPR cells to complete several cell functions including acetate uptake and PHA storage. However, the glycolytic pathway is efficiently operable at warm temperatures (> 20 degrees C). The reduced performance of enhanced EBPR facilities operated at warm temperature may not be a result of GAO proliferation; instead it may be related the efficient use of the glycolytic pathway by PAOs which results in more glycogen storage and less P uptake, thereby reducing the EBPR performance.
在全规模和实验室规模的强化生物除磷（EBPR）研究中，EBPR性能的下降与聚糖菌（GAOs）的增殖有关，但往往缺乏任何证据。在本研究中，通过详细的酶学研究结合批次试验和电子显微镜结果给出了一个合理的解释。由于所提供的短批次试验周期不允许菌群转移，结果排除了因菌群从聚磷菌（PAO）转移到GAO或其他非PAO而导致性能下降的可能性，电子显微镜结果进一步证实了这一点。结果表明，糖原不仅作为聚羟基脂肪酸酯（PHA）生产的还原力来源，而且在PAO的聚磷库耗尽时作为替代能源。在5摄氏度时，通过糖酵解途径缓慢生成的三磷酸腺苷（ATP）无法满足EBPR细胞完成包括乙酸摄取和PHA储存在内的多种细胞功能的能量需求。然而，糖酵解途径在温暖温度（>20摄氏度）下可有效运行。在温暖温度下运行的强化EBPR设施性能下降可能不是GAO增殖的结果；相反，可能与PAO对糖酵解途径的有效利用有关，这导致更多的糖原储存和更少的磷摄取，从而降低了EBPR性能。
