Structure and regulation of aroH, the structural gene for the tryptophan-repressible 3-deoxy-D-arabino-heptulosonic acid-7-phosphate synthetase of Escherichia coli.
Structure and regulation of aroH, the structural gene for the tryptophan-repressible 3-deoxy-D-arabino-heptulosonic acid-7-phosphate synthetase of Escherichia coli.
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aroH 的结构和调控，aroH 是大肠杆菌色氨酸抑制性 3-脱氧-D-阿拉伯-庚糖酸-7-磷酸合成酶的结构基因。
DOI：
10.1016/0022-2836(81)90334-x
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发表时间：
1981
影响因子：
5.6
通讯作者：
Yanofsky,C
中科院分区：
文献类型：
--
作者：
Zurawski,G;Gunsalus,RP;Brown,KD;Yanofsky,C
克隆了大肠杆菌色氨酸抗性3-脱氧-d-阿拉伯-庚磺酸-7-磷酸合成酶的结构基因，并进行了部分序列测定。用体外合成的aroH蛋白进行氨基酸序列分析，确定翻译起始位点和假定翻译终止位点。玻璃体转录起始于相隔三个碱基对的两个起始点中的任何一个。虽然转录起始点位于翻译起始点之前约120个碱基对，但在前导区似乎没有转录终止位点。活体中进行的调节研究支持这一结论，并表明抑制可能是用于控制这一单基因操纵子表达的唯一特定调节机制。核糖核酸聚合酶和转录增压子结合在aroH启动子的−35区域，位于与操纵子操纵子同源的区域。由于转录操纵子操纵子与−10重叠，但与−启动子的RNA35区域不重叠，因此转录抑制因子似乎通过与各自启动子中不同的RNA聚合酶识别区域结合来抑制这两个操纵子的转录启动。
The structural gene for the tryptophan-repressible 3-deoxy-d-arabino-heptulosonic acid-7-phosphate synthetase ofEscherichia coli, aroH, has been cloned and partially sequenced. The translation start site and presumed translation stop site were identified by amino acid sequence analyses witharoHprotein synthesizedin vitro. Transcriptionin vitrois initiated at either of two start sites, three base-pairs apart. Although the transcription start sites are located approximately 120 base-pairs before the translation start site, there does not appear to be a site of transcription termination in the leader region. Regulatory studies performedin vivosupport this conclusion and suggest that repression may be the sole specific regulatory mechanism used to control expression of this single gene operon. RNA polymerase andtrprepressor bind at the −35 region of thearoHpromoter, in a region homologous to the operator of thetrpoperon. Since thetrpoperon operator overlaps the −10 but not the −35 region of thetrppromoter, it appears thattrprepressor inhibits transcription initiation in the two operons by binding to different RNA polymerase recognition regions in the respective promoters.