Structure and expression of the cytochrome aa3 regulatory gene ctaA of Bacillus subtilis.
Structure and expression of the cytochrome aa3 regulatory gene ctaA of Bacillus subtilis.
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枯草芽孢杆菌细胞色素aa3调控基因ctaA的结构和表达。
DOI：
10.1128/jb.171.9.4979-4986.1989
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发表时间：
1989
影响因子：
3.2
通讯作者：
Taber,HW
中科院分区：
文献类型：
--
作者：
Mueller,JP;Taber,HW
定义枯草芽孢杆菌ctaA基因的突变阻断细胞色素aa3形成和孢子形成。我们最近描述了ctaA基因座的分离和初步表征。通过RNA酶保护实验对体内mRNA转录物的分析定位ctaA转录物的5'和3'末端，证实了单顺反子结构。通过使用核酸酶保护试验，在稳态ctaA mRNA的丰度增加，观察到在孢子形成的开始，随后在随后的阶段减少。源自ctaA基因的转录物在指数生长结束后2.0小时最丰富。通过将ctaA基因的转录与整合质粒载体中的lacZ偶联，证实了ctaA mRNA积累的这种模式。ctaA的表达不受葡萄糖抑制，并且不依赖于spoOA和spoOH（sigH）基因产物。发现指数后表达依赖于strC基因的产物。ctaA的表达似乎以生长阶段特异性的方式进行调节。通过高分辨率S1核酸酶保护实验鉴定的转录起始位点之前是单个sigma A依赖性启动子序列。
Mutations that define the ctaA gene of Bacillus subtilis block cytochrome aa3 formation and sporulation. We have recently described the isolation and initial characterization of the ctaA locus. Analysis of in vivo mRNA transcripts by RNase protection experiments located the 5' and 3' termini of the ctaA transcript, confirming a monocistronic structure. By using a nuclease protection assay, an increase in the abundance of steady-state ctaA mRNA was observed during the initiation of sporulation, followed by a decrease during subsequent stages. Transcripts originating from the ctaA gene were most abundant 2.0 h after the end of exponential growth. This pattern of ctaA mRNA accumulation was confirmed by coupling the transcription of the ctaA gene to lacZ in an integrative plasmid vector. Expression of ctaA was not repressed by glucose and was independent of the spoOA and spoOH (sigH) gene products. Postexponential expression was found to be dependent on the product of the strC gene. The expression of ctaA appears to be regulated in a growth stage-specific manner. The transcriptional start site, identified by high-resolution S1 nuclease protection experiments, was preceded by a single sigma A-dependent promoter sequence.