Accumulibacter菌群结构及代谢行为对环境压力的响应及调控

Accumulibacter have been reported as the putative PAOs, in which various clades have different metabolic properties. So far, the manipulation methods for enrichment of different Accumulibacter clades and it’s response to environmental changes are still lacked. Under some environmental stresses, the metabolic pathway of polyphosphate accumulating organisms (PAOs) will shift to that of glycogen accumulating organisms (GAOs) so that the performance of enhanced biological phosphorus removal (EBPR) system will be affected. However, there is little known regarding the mechanisms of metabolic shift. Regarding Accumulibacter type as main objects, with the combined methods of chemical analysis and molecular biotechniques, the sequencing batch reactor (SBR) systems will be employed to investigate the changes of Accumulibacter metabolic behavior and population structure under different environmental stresses. The metabolic shift mechanism from polyphosphate accumulating metabolism (PAM) to glycogen accumulating metabolism (GAM) will be researched in detail, in which clades composition and intracellular polymer transformation are monitored. Moreover, the enrichment methods of Accumulibacter I and II will be explored. The community structure and function of Accumulibacter will be monitored in post anoxic SBR system. The effective metabolic behavior manipulation methods will be investigated which can improve phosphorus and nitrogen removal efficiencies. The implementation of this research will be helpful to the improvement of PAOs metabolic models and contribute to afford a better design and operation of biological nutrient removal process.

Accumulibacter是公认的一类聚磷菌，其各进化枝在代谢特性上存在差别，但缺乏对不同进化枝的富集方法及其对环境变化响应的深入了解。某些环境压力下，聚磷菌代谢会出现向聚糖菌代谢的转换，影响除磷性能，但机制不明。拟采用序批式反应器，以Accumulibacter为对象，结合化学分析和分子生物技术，研究Accumulibacter在不同环境压力下的代谢行为及其菌群结构变化，重点研究Accumulibacter发生聚糖菌代谢行为的机制，监测其各进化枝组成和胞内聚合物的转化，考察其代谢转换的原因；研究不同类型Accumulibacter的富集方法；考察后置缺氧序批式反应器内的Accumulibacter功能和菌群组成，研究调控该系统内反硝化聚磷菌代谢行为的措施，提高除磷脱氮效率。该课题的完成有助于改进现有的聚磷菌代谢模型，并提出更加高效稳定的生物除磷脱氮工艺的设计方法和运行方式。

采用生物除磷脱氮反应器，研究了不同类型Accumulibacter(I和II)的富集方法；并对分别富集了不同优势Accumulibacter的系统的反硝化能力进行了考察；研究了厌氧-好氧-缺氧运行模式下SBR系统内聚磷菌的代谢行为，考察聚磷菌在此模式下储存和利用有机碳源的特性；还对低聚磷条件下分别富集Accumulibacter I和II型聚磷菌的代谢特性进行了研究，发现短期低聚磷条件下，两类Accumulibacter的代谢均会出现聚糖代谢的行为；而Accumulibacter I比II更适应长期低聚磷条件。此外，低温（10 °C）和钙离子浓度也会影响Accumulibacter聚磷菌的代谢模式。该课题的完成揭示了特定条件下聚磷菌的代谢转化机制，为提高生物除磷系统的稳定性和可靠性提供了新思路。