Bidirectional promoter in the hut(P) region of the histidine utilization (hut) operons from Klebsiella aerogenes.
Bidirectional promoter in the hut(P) region of the histidine utilization (hut) operons from Klebsiella aerogenes.
复制标题
来自产气克雷伯菌的组氨酸利用 (hut) 操纵子的 hut(P) 区域中的双向启动子。
DOI：
10.1128/jb.170.5.2240-2246.1988
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发表时间：
1988
影响因子：
3.2
通讯作者：
Bender,RA
中科院分区：
文献类型：
--
作者：
Nieuwkoop,AJ;Baldauf,SA;Hudspeth,ME;Bender,RA
产气克雷伯菌组氨酸利用 (hut) 操纵子的 hut(P) 区域（即负责调节 hutUH 表达的区域）含有双向启动子。该启动子的一个转录本编码 hutUH 操纵子；相反定向转录物的作用尚不清楚，尽管它似乎参与调节 hutUH 表达(A.J. Nieuwkoop, S.A. Boylan, and R.A. Bender, J. Bacteriol. 159:934-939, 1984)。含有 hut(P) 的 247 个碱基对 (bp) 片段携带两个 RNA 聚合酶结合位点，与在体外和体内由 hut(P) DNA 产生的两个转录本的起始位点一致。结合位点共享一个 4 bp 区域，表明调节位点的占据排除了 hutUH 启动子的占据，反之亦然。在缺乏正效应子的情况下，与负责 hutUH 转录的位点的结合弱于与负责调节的位点的结合。含有 hut(P) 的 250 bp 片段的核苷酸序列包含与大肠杆菌启动子共有序列的两个可能的匹配，一个较好的匹配和一个较差的匹配，分别对应于较强和较弱的 RNA 聚合酶结合位点的位置。该序列还包含与大肠杆菌分解代谢物基因激活蛋白结合的共有序列相似的区域。还发现了与 Ntr 依赖性启动子的共有序列相似的序列，与两个 RNA 聚合酶结合位点重叠，但它不是功能性启动子。最后，起始密码子前面是 Shine-Dalgarno 共有序列，后面是开放阅读框，确定了 hutU 基因编码序列的可能起始位置。
The hut(P) region (i.e., the region responsible for regulation of hutUH expression) of the Klebsiella aerogenes histidine utilization (hut) operons contains a bidirectional promoter. One transcript from this promoter encodes the hutUH operon; the role of the oppositely directed transcript is unknown, although it appears to be involved in regulating hutUH expression (A.J. Nieuwkoop, S.A. Boylan, and R.A. Bender, J. Bacteriol. 159:934-939, 1984). A 247-base-pair (bp) fragment containing hut(P) carries two RNA-polymerase-binding sites agree with the start sites of the two transcripts produced from hut(P) DNA in vitro and in vivo. The binding sites share a 4-bp region, suggesting that occupancy of the regulatory site precludes occupancy of the hutUH promoter, and vice versa. In the absence of positive effectors, the binding to the site responsible for hutUH transcription is weaker than the binding to the site responsible for regulation. The nucleotide sequence of the 250-bp fragment containing hut(P) contains two possible matches to the consensus sequence for Escherichia coli promoters, a better and worse match, corresponding in position to the stronger and weaker RNA-polymerase-binding sites, respectively. The sequence also contains a region similar to the consensus sequence for binding of the catabolite gene activator protein of E. coli. A sequence similar to the consensus for Ntr-dependent promoters was also found, overlapping both RNA-polymerase-binding sites, but it is not a functional promoter. Finally, an initiation codon preceded by a Shine-Dalgarno consensus sequence and followed by an open reading frame identifies a probable start of the hutU gene coding sequences.