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在ｐＲＫ２９０载体上将粪产碱菌固氮酶基因ｎｉｆＨ的启动子与报告基因ＬａｃＺ相融合，获得表达载体ｐＳＫ６，并转导到粪产碱菌Ａ１５０１菌株中，探讨了铵和氧对该启动子的表达调控．结果表明，粪产碱菌ｎｉｆＨ启动子仍受到铵和氧的调节．当铵浓度大于３ｍｍｏｌ／Ｌ时，其表达水平大幅度下降，但铵浓度高达４０ｍｍｏｌ／Ｌ，仍有很低水平表达．而且，带有巴西固氮螺菌ｎｉｆＨ∶ｌａｃＺ的粪产碱菌接合子在高铵条件下（４０ｍｍｏｌ／Ｌ）也有低水平表达．此外，氧对粪产碱菌的ｎｉｆＨ启动子有抑制作用，这在无铵条件下表现最为明显．
The promoter of nifH of Alcaligenes aureus nitrogenase gene was fused with reporter LacZ on pRK290 vector to obtain expression vector pSK6 and transduced into Alcaligenes faecalis A1501 strain. The effects of ammonium and oxygen on the promoter of Regulation of expression. The results show that the nifH promoter of Alcaligenes faecalis is still regulated by ammonium and oxygen. When the concentration of ammonium was more than 3mmol / L, its expression level dropped significantly, but the ammonium concentration was as high as 40mmol / L, and there was still a low level of expression. Moreover, Alcaligenes faecalis conjugates harboring Azospirillum nifH: lacZ also showed low levels of expression under high ammonium conditions (40 mmol / L). In addition, oxygen inhibits the nifH promoter of Alcaligenes faecalis, which is most pronounced in the absence of ammonium.