Removal of Mg2+ inhibition benefited the growth and isolation of ammonia-oxidizing bacteria: An inspiration from bacterial interaction
Removal of Mg2+ inhibition benefited the growth and isolation of ammonia-oxidizing bacteria: An inspiration from bacterial interaction
复制标题
去除 Mg2 抑制有利于氨氧化细菌的生长和分离：细菌相互作用的启发
DOI：
10.1016/j.scitotenv.2022.155923
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发表时间：
2022
影响因子：
9.8
通讯作者：
Jianfei Luo
中科院分区：
文献类型：
--
作者：
Buchan Liu;Weitie Lin;Shenxi Huang;Qiuyun Sun;Hao Yin;Jianfei Luo
氨氧化细菌在全球氮循环中起着重要作用，在废水脱氮中有着广泛的应用。然而，由于氨氧化细菌对环境因素的敏感性，且通常与其他微生物形成紧密的关系，使得氨氧化细菌的分离和维护困难且耗时。研究发现，氨氧化菌与其共生菌之间的相互作用能够促进氨氧化反应的进行;在共培养过程中，共生菌对培养基中镁离子（Mg 2+）的去除率高达36.7%，这是氨氧化反应得以促进的主要原因。在AOB菌株纯培养过程中，当Mg 2+浓度降低到较低水平时，其氨氧化活性比初始培养基中培养的菌株提高了5倍以上，amoA基因表达量提高了12倍以上。在新设计的培养基上，氨氧化菌在液体培养中的氨氧化能力明显增强，在琼脂平板上形成数量多、直径大的可见菌落。在添加高浓度碳酸钙（CaCO 3）的条件下，通过观察AOB菌落周围形成的水解带，可以方便而特异地鉴定AOB菌落。在短时间内从不同样品中成功分离出了多株AOB，表明该培养基和策略在环境中分离AOB的可行性和有效性。·AOB与其细菌伴侣之间的关系促进了氨氧化。·共培养中异养菌的生长对Mg 2+的去除有促进作用。·去除Mg 2+有利于纯培养条件下氨氧化菌的氨氧化。去除Mg 2+有利于AOB在琼脂平板上形成殖民地。·根据CaCO 3的水解带可以容易地鉴定AOB菌落。
Ammonia-oxidizing bacteria (AOB) play an important role in the global nitrogen cycle and have broad applications in the nitrogen removal from wastewater. However, the AOB species are sensitive to environmental factors and usually form tight relationships with other microbes, making the AOB isolation and maintenance are difficult and time-consuming. In this study, the relationship that occurred between AOB and their bacterial partners was found to be able to improve the ammonia oxidation; during the co-cultivation, the magnesium ions (Mg 2+ ) with removal rate as high as 36.7% was removed from culture medium by the concomitant bacterial species, which was regarded as the main reason for improving ammonia oxidation. During the pure cultivation of AOB isolate, when the concentration of Mg 2+ reduced to low levels, the ammonia-oxidizing activity was more than 5 times and the amoA gene expression was more than 12 times higher than that grown in the initial culture medium. Based on a newly designed culture medium, the ammonia oxidation of AOB isolate grown in liquid culture was significantly promoted and the visible AOB colonies with much more number and larger diameter were observed to form on agar plates. With the addition of high concentration of calcium carbonate (CaCO 3 ), AOB colonies could be easily and specifically identified by following the hydrolytic zones that formed around AOB colonies. Another AOB isolates were successively obtained from different samples and within a short time, suggesting the feasibility and effectivity of this culture medium and strategy on the AOB isolation from environments. • The relationship between AOB and its bacterial partners improve the ammonia oxidation. • The heterotroph grown in co-cultivation contributed to the removal of Mg 2+ . • Removal of Mg 2+ benefited to the ammonia oxidation of AOB grown in pure cultivation. • Removal of Mg 2+ benefited to the colony formation of AOB grown on agar plates. • AOB colonies could be easily identified following the hydrolytic zones of CaCO 3 .