Abstract：
In this study, the possibility of an auto-aggregating bacterium Pseudomonas strain XL-2 with heterotrophic nitrification-aerobic denitrification capacity for improving granulation and nitrogen removal was evaluated. The results showed that the supplementation of strain XL-2 promoted granulation, making R1 (experimental group with strain XL-2) dominated by granules at 14 d, which was 12 days earlier than R2 (control group without strain XL-2). This was attributed to the promotion of extracellular polymeric substances (EPS) secretion, particularly proteins by adding strain XL-2, thereby improving the hydrophobicity of sludge and altering the proteins secondary structures to facilitate aggregation. Meanwhile, adding strain XL-2 improved simultaneous nitrification and denitrification efficiency of R1. Microbial community analysis indicated that strain XL-2 successfully proliferated in aerobic granule sludge and might induce the enrichment of genera such as Flavobacterium and Paracoccus that were favorable for EPS secretion and denitrification, jointly promoting granulation and enhancing nitrogen removal efficiency.
摘要：
在这项研究中,评估了具有异养硝化-好氧反硝化能力的自聚集细菌Pseudomonas菌株XL-2改善颗粒化和氮去除的可能性。结果表明，补充菌株XL-2促进了肉芽形成，使R1(实验组用XL-2菌株)在14d以颗粒为主，比R2(无菌株XL-2的对照组)早12天。这归因于细胞外聚合物（EPS）分泌的促进，特别是通过添加菌株XL-2的蛋白质,从而改善污泥的疏水性并改变蛋白质二级结构以促进聚集。同时,添加菌株XL-2提高了R1的同步硝化反硝化效率。微生物群落分析表明，XL-2菌株在好氧颗粒污泥中成功增殖，并可能诱导黄杆菌和副球菌等有利于EPS分泌和反硝化的属的富集。共同促进造粒和提高脱氮效率。
