National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Beijing University of Technology, Beijing 100124, China.
National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Beijing University of Technology, Beijing 100124, China.
Bioresour Technol. 2021 Aug;333:125189. doi: 10.1016/j.biortech.2021.125189. Epub 2021 Apr 18.
The utilization of halophilic bioresources is limited due to a lack of isolation and characterization work. A halophilic bacterium strain SND-01 of Exiguobacterium mexicanum was isolated in this study, which is the first report on its novel function in heterotrophic nitrification-aerobic denitrification (HN-AD). The strain SND-01 is slightly halophilic, surviving at 0 up to 9% (w/v) salinity. When utilizing ammonium, nitrate or nitrite as the sole nitrogen source in aerobic conditions, the isolated strain showed the maximum nitrogen removal rate of 2.24 ± 0.14 mg/(L·h), 3.63 ± 0.21 mg/(L·h) and 2.30 ± 0.23 mg/(L·h), respectively. Functional genes and key enzymes involved in heterotrophic-aerobic nitrogen transformations were characterized, establishing the pathway of HN-AD. The nitrogen removal via HN-AD is dependent on the C/N ratio, salinity and temperature. The halophilic Exiguobacterium mexicanum strain SND-01 shows a significant potential in biotreatment of saline wastewater in an easy and cost-effective way.
由于缺乏分离和表征工作，嗜盐生物资源的利用受到限制。本研究分离到一株嗜盐细菌 SND-01，属于极端嗜盐菌微杆菌属，这是首次报道其在异养硝化-好氧反硝化（HN-AD）中的新功能。该菌株 SND-01 轻度嗜盐，在 0 至 9%（w/v）盐度下仍能存活。当利用铵盐、硝酸盐或亚硝酸盐作为唯一氮源在好氧条件下时，分离出的菌株表现出最大的氮去除率分别为 2.24 ± 0.14、3.63 ± 0.21 和 2.30 ± 0.23 mg/（L·h）。对参与异养-好氧氮转化的功能基因和关键酶进行了表征，建立了 HN-AD 途径。HN-AD 脱氮依赖于 C/N 比、盐度和温度。嗜盐极端微杆菌 SND-01 菌株在以简单且具有成本效益的方式处理含盐废水方面具有很大的潜力。
