Deng X, Shen S
Laboratory of Molecular Genetics, Shanghai Institute of Plant Physiology, Chinese Academy of Sciences.
Sci China B. 1995 Jan;38(1):60-6.
The nucleotide sequence of the nifLA promoter of Enterobacter cloacae E26 was determined, and the transcription start site of nifLA was mapped by the primer extension. Studies on the oxygen regulation of E. cloacae nifLA promoter with the nifL'-lacZ fusion showed that the nifLA promoter was sensitive to oxygen as Klebsiella pneumoniae nifLA promoter reported previously. Comparison between the nifLA promoter sequences of E. cloacae and K. pneumoniae revealed the presence of an 11-bp conserved sequence between the -24/-12 consensus of sigma 54-dependent promoter and NtrC binding motif. The 11-bp sequence is speculated to be involved in the oxygen regulation of the nifLA promoter of both enteric bacteria.
测定了阴沟肠杆菌E26固氮nifLA启动子的核苷酸序列，并通过引物延伸法确定了nifLA的转录起始位点。利用nifL'-lacZ融合对阴沟肠杆菌nifLA启动子的氧调节进行研究，结果表明，与先前报道的肺炎克雷伯菌nifLA启动子一样，阴沟肠杆菌nifLA启动子对氧敏感。阴沟肠杆菌和肺炎克雷伯菌nifLA启动子序列的比较显示，在依赖于σ54的启动子的-24/-12共有序列与NtrC结合基序之间存在一个11bp的保守序列。推测该11bp序列参与了这两种肠道细菌nifLA启动子的氧调节。
