海洋异养硝化菌株的快速筛选

Rapid screening of marine heterotrophic nitrobacteria

目前尚缺乏有效地系统分离获得异养硝化菌的方法,为此,利用海洋养殖废水,采用前期自养后期异养的混养富集方法,获得具有异养脱氮能力的菌群.通过异养培养基分离获得纯菌株,利用特异性引物扩增分离菌株的氨单加氧酶(AMO)基因amoA和周质硝酸盐还原酶(NAR)亚基基因napA,快速筛选具有潜在异养硝化或异养硝化好氧反硝化能力的菌株.通过氮素转化试验确认菌株的氮代谢特性.共分离获得异养细菌22株,其中11株细菌amoA基因呈阳性,7株细菌amoA基因和napA基因同时显阳性,氮素转化试验证明9株细菌具有异养脱氮能力.

Method of mixed culture,earlier autotrophic condition and later heterotrophic condition,was used to enrich heterotrophic nitrifying bacteria and aerobic denitrifying bacteria from marine aquaculture wastewater.Heterotrophic nitrifying bacteria and aerobic denitrifying bacteria were isolated and purified by the heterotrophic culture medium.Using the special PCR primers,the bacteria were rapidly screened by amplifying Ammonia monooxygenase encoding gene（amoA） and a subunit of periplasmic nitrate reductase（NAR） encoding gene（napA）.Those bacteria were identified by the denitrifying test.22 heterotrophic bacteria strains were isolated,11 strains had the amoA gene,7 strains had both of the two genes,and there were 9 strains which had nitrifying ability.