CAJ | 학술논문

通过异养硝化培养基获得一株高效脱氮细菌,并通过形态学特征、生理生化反应及16S rDNA同源性比较对筛得菌株进行了鉴定;分别以NO_3~--N和NO_2~--N为唯一氮源,通过对脱氮过程中各种含氮代谢物的定量及对脱氮相关基因氨单加氧酶基因(amoA)、羟胺氧化酶基因(hao)、周质硝酸盐还原酶亚基基因(napA)的扩增及测序比较,对该菌株的生理途径及脱氮机理进行了研究.结果表明,高效脱氮细菌YY-5不能发生好氧反硝化,但能在3 d内将氨氮由95.23 mg/L降解至1.29 mg/L,降解率达妻98.6%,同时未发现亚硝酸盐氮、硝酸盐氮积累;对该菌主要代谢气体产物进行检测,发现CO_2和N_2明显增多,无N_2O生成;经鉴定,初步判定该菌为不动杆菌属,命名为Acinetobacter sp.YY-5;从该菌基因组中均能扩增出amoA、hao、napA等基因,其中napA与hao基因与已报道的napA与hao基因进行Blaster较,发现具有较大差别.图6表3参15
통과이양초화배양기획득일주고효탈담세균,병통과형태학특정、생리생화반응급16S rDNA동원성비교대사득균주진행료감정;분별이NO_3~--N화NO_2~--N위유일담원,통과대탈담과정중각충함담대사물적정량급대탈담상관기인안단가양매기인(amoA)、간알양화매기인(hao)、주질초산염환원매아기기인(napA)적확증급측서비교,대해균주적생리도경급탈담궤리진행료연구.결과표명,고효탈담세균YY-5불능발생호양반초화,단능재3 d내장안담유95.23 mg/L강해지1.29 mg/L,강해솔체처98.6%,동시미발현아초산염담、초산염담적루;대해균주요대사기체산물진행검측,발현CO_2화N_2명현증다,무N_2O생성;경감정,초보판정해균위불동간균속,명명위Acinetobacter sp.YY-5;종해균기인조중균능확증출amoA、hao、napA등기인,기중napA여hao기인여이보도적napA여hao기인진행Blaster교,발현구유교대차별.도6표3삼15
An aerobic heterotrophic bacterium YY-5, which could degrade NH_4~(+)-N from 95.23 mg/L to 1.29 mg/L in 3 days, was studied to reveal its denitrification methanism at the level of product characteristics and several denitrification enzymes encoding genes. The results demonstrated the bacteria produced large quantities of CO_2 and N_2, but small nitrite and nitrate accumulations. Furthermore, strain YY-5 had ammonia monooxygenase encoding gene (amoA) which encodes the enzyme to oxidize ammonia to hydroxylamine. Also, the strain had a new hydroxylamine oxidoreductase encoding gene (hao) whose sequence was distinct not only to that of autotrophic bacteria but also to that of heterotrophie bacteria. Its napA gene was also great different with the reported genes from the known aerobic heterotrophic bacteria by Blast comparison. The strain was identified as Acinetobacter sp. YY-5 according to its morphological, physiological and biochemical characters, as well as 16S rDNA sequence homology comparison. Fig 6, Tab 3, Ref 15