Pseudomonas oryzihabitans EN-F4菌株的脱氮特征及羟胺对其脱氮过程的促进作用  

Nitrogen removal characteristics of Pseudomonas oryzihabitans EN-F4 with/without the supplementation of hydroxylamine

作　　者：谢尧旭 张漫漫 何腾霞 卢海凤 陈亚 XIE Yaoxu;ZHANG Manman;HE Tengxia;LU Haifeng;CHEN Ya(Key Laboratory of Plant Resource Conservation and Germplasm Innovation in Mountainous Region(Ministry of Education),College of Life Sciences/Institute of Agro-bioengineering,Guizhou University,Guiyang 550025,Guizhou,China)

机构地区：[1]贵州大学生命科学学院/农业生物工程研究院、山地植物资源保护与种质创新教育部重点实验室,贵州贵阳550025

出　　处：《微生物学报》2023年第10期3858-3875,共18页Acta Microbiologica Sinica

基　　金：国家自然科学基金(42007223,42167019);贵州省科技计划(黔科合基础-ZK[2021]一般233);贵州省普通高等学校青年科技人才成长项目(黔教合KY字[2021]086);贵州大学培育项目(贵大培育[2019]50号);大学生“SRT计划”(贵大SRT字[2022]443号)。

摘　　要：【目的】异养硝化-好氧反硝化(heterotrophic nitrification-aerobic denitrification,HN-AD)微生物在生物脱氮中具有重要作用,而能同时去除废水中多种无机氮尤其是羟胺的HN-AD微生物报道较少。本研究从菜地中分离筛选出一株能同时去除羟胺和亚硝酸盐的HN-AD菌株EN-F4,探究其脱氮特征以及羟胺对其脱氮过程的影响,为提高废水处理效率奠定基础。【方法】通过形态学和16S rRNA基因测序对该菌株进行鉴定,并利用批量试验研究该菌株的脱氮特征,结合氮平衡、酶活性和特异性酶抑制剂探索菌株的HN-AD机理,最后通过添加羟胺研究其对不同氮源转化的影响。【结果】菌株EN-F4经鉴定为栖稻假单胞菌(Pseudomonas oryzihabitans),该菌株在25℃条件下对铵盐、羟胺、亚硝酸盐和硝酸盐的去除效率分别为99.27%、99.13%、87.01%和85.20%,对应的最大去除速率分别为8.27、1.85、5.10和5.31 mg/(L·h)。更突出的是,外加羟胺后不会抑制该菌的反硝化能力,反而促进了亚硝酸盐和总氮的去除,其最大去除速率分别提升至7.80 mg/(L·h)和7.51 mg/(L·h)。结合酶活性的成功检测、氮平衡和HN-AD特异性酶抑制剂分析证实了菌株具有优异的HN-AD能力。【结论】菌株Pseudomonas oryzihabitans EN-F4可以在25℃条件下高效地进行HN-AD去除废水中的多种无机氮,且羟胺能显著促进亚硝酸盐和总氮的去除。[Objective]The microorganisms with the function of heterotrophic nitrification-aerobic denitrification(HN-AD)play a key role in the biological removal of nitrogen,while little is known about the HN-AD microorganisms capable of simultaneous removing multiple inorganic nitrogen sources,especially hydroxylamine,from wastewater.In this study,a HN-AD strain EN-F4 capable of simultaneous removing hydroxylamine and nitrite was isolated from a vegetable field.We explored its nitrogen removal characteristics and the effects of hydroxylamine on the nitrogen conversion process,aiming to lay a foundation for improving the efficiency of wastewater treatment.[Methods]The strain EN-F4 was identified based on morphological characteristics and 16S rRNA gene sequence.Batch experiments were carried out to determine the nitrogen conversion characteristics of the strain EN-F4.The nitrogen balance,enzyme activity,and specific enzyme inhibitor tests were conducted to decipher the HN-AD mechanism of the strain EN-F4.Finally,the effects of hydroxylamine addition on the conversion of different nitrogen sources were explored.[Results]The isolate EN-F4 was identified as Pseudomonas oryzihabitans.The strain cultured at 25℃showed the ammonium,hydroxylamine,nitrite,and nitrate removal efficiencies of 99.27%,99.13%,87.01%,and 85.20%and the maximum nitrogen removal rates of 8.27,1.85,5.10,and 5.31 mg/(L·h),respectively.The addition of hydroxylamine did not inhibit the denitrifying ability of the strain EN-F4,while it promoted the removal of nitrite and total nitrogen by the strain,with the maximum removal rates reaching 7.80 and 7.51 mg/(L·h),respectively.The enzyme activity,nitrogen balance,and specific enzyme inhibitors confirmed the strong HN-AD capability of the strain.[Conclusion]Pseudomonas oryzihabitans EN-F4 could efficiently remove inorganic nitrogen sources from wastewater by HN-AD at 25℃,and hydroxylamine could significantly promote the removal of nitrite and total nitrogen.

关 键 词：Pseudomonas oryzihabitans 异养硝化-好氧反硝化 酶活 抑制剂 氮平衡 

分 类 号：X703[环境科学与工程—环境工程] X172