摘要
该研究采用选择性培养基从汾河底泥中分离筛选异养硝化-好氧反硝化菌,通过形态观察、生理生化试验及分子生物学技术对其进行菌种鉴定,并对其氨氮(NH_(4)^(+)-N)降解过程进行动态监测,测定NH_(4)^(+)-N降解过程中关键酶的基因及酶活。结果表明,分离筛选得到一株异养硝化-好氧反硝化菌,编号为ZH-2,其被鉴定为醋酸钙不动杆菌(Acinetobacter calcoaceticus)。该菌在NH_(4)^(+)-N降解过程中存在NO_(3)^(-)-N和NO_(2)^(-)-N两种中心代谢产物,其基因组中含有3种关键酶(氨单加氧酶(Amo)、硝酸盐还原酶(Nap)和亚硝酸盐还原酶(Nir))基因,在NH_(4)^(+)-N降解过程,这3种关键酶的比酶活分别为45.69 m U/mg、3.54 m U/mg和6.91 m U/mg。综上,初步确定A.calcoaceticus ZH-2的NH_(4)^(+)-N降解过程是NH_(4)^(+)-N→NH_(2)OH→NO_(2)^(-)-N→NO_(3)^(-)-N→NO_(2)^(-)-N→NO→N_(2)O→N_(2)的经典降解途径,为该菌的进一步推广应用提供了理论依据。
In this study,heterotrophic nitrifification-aerobic denitrification strains were isolated and screened from the sediment of the Fenhe River using selective medium,and they were identified by morphological observation,physiological and biochemical tests and molecular biology techniques.The ammonia nitrogen(NH_(4)^(+)-N)degradation process was dynamically monitored,and the genes and enzyme activities of key enzymes during NH_(4)^(+)-N degradation were determined.The results showed that a heterotrophic nitrifification-aerobic denitrification bacterium was isolated and screened,numbered as ZH-2,and identified as Acinetobacter calcoaceticus.Two central metabolites,NO_(3)^(-)-N and NO_(2)^(-)-N were present in the NH_(4)^(+)-N degradation process of the strain.Its genome contained 3 key enzymes(ammonia monooxygenase(Amo),nitrate and periplasmic nitrate reductases(Nap)and nitrite reductase(Nir))genes,During the NH_(4)^(+)-N degradation process,the specific enzyme activities of these 3 key enzymes were 45.69 mU/mg,3.54 mU/mg and 6.91 mU/mg,respectively.In summary,the NH_(4)^(+)-N degradation process of A.calcoaceticus ZH-2 was preliminarily determined as the classical degradation pathway of NH_(4)^(+)-N→NH_(2)OH→NO_(2)^(-)-N→NO_(3)^(-)-N→NO_(2)^(-)-N→NO→N_(2)O→N_(2),which provided a theoretical basis for the further popularization and application of the strain.
作者
张泽锟
闫勇
郭静
胡青平
ZHANG Zekun;YAN Yong;GUO Jing;HU Qingping(College of Life Science,Shanxi Normal University,Taiyuan 030031,China)
出处
《中国酿造》
CAS
北大核心
2022年第8期83-88,共6页
China Brewing
基金
山西省自然基金面上项目(201801D121206)。
关键词
异养硝化-好养反硝化菌
分离
鉴定
氨氮降解
heterotrophic nitrification-aerobic denitrification strain
isolation
identification
ammonia nitrogen degradation
