A monoamine-regulated Klebsiella aerogenes operon containing the monoamine oxidase structural gene (maoA) and the maoC gene
A monoamine-regulated Klebsiella aerogenes operon containing the monoamine oxidase structural gene (maoA) and the maoC gene
复制标题
含有单胺氧化酶结构基因 (maoA) 和 maoC 基因的单胺调节产气克雷伯菌操纵子
作者：
H. Sugino;M. Sasaki;H. Azakami;M. Yamashita;Y. Murooka
产气克雷伯菌基因maoA参与单胺氧化酶的合成，由酪胺和相关化合物诱导，经过分解代谢物和铵离子抑制，并被克隆。确定了参与单胺氧化酶合成的区域的核苷酸序列。发现了两个开放阅读框：maoA 基因和迄今为止未知的基因（maoC）。它们位于潜在的启动子序列和转录终止子序列之间。发现了大肠杆菌染色体上与克雷伯菌 maoA 基因高度同源的区域。潜在的maoA基因位于大肠杆菌染色体上的30.9分钟处。对纯化的单胺氧化酶的N末端的前11个氨基酸的氨基酸序列的分析与从maoA基因的核苷酸序列推导的结果一致。前导肽延伸超过30个氨基酸并具有信号序列的特征。体内生成的转录物的引物延伸和 S1 核酸酶图谱表明，酪胺诱导的 mRNA 起始于 maoC 基因 ATG 起始密码子上游 62 个碱基的位点。在推定的启动子区域中，发现与环AMP受体蛋白结合位点的共有序列高度相似。因此，mao区域由两个顺反子组成，并且mao操纵子受到单胺化合物、葡萄糖和铵离子的调节。
The Klebsiella aerogenes gene maoA, which is involved in the synthesis of monoamine oxidase, was induced by tyramine and the related compounds, subjected to catabolite and ammonium ion repression, and cloned. The nucleotide sequence of the region involved in monoamine oxidase synthesis was determined. Two open reading frames, the maoA gene and a hitherto unknown gene (maoC), were found. These are located between a potential promoter sequence and a transcriptional terminator sequence. A region of the Escherichia coli chromosome that was highly homologous to the Klebsiella maoA gene was found. The potential maoA gene is located at 30.9 min on the E. coli chromosome. Analysis of the amino acid sequences of the first 11 amino acids from the N terminus of the purified monoamine oxidase agrees with those deduced from the nucleotide sequence of the maoA gene. The leader peptide extends over 30 amino acids and has the characteristics of a signal sequence. Primer extension and S1 nuclease mapping of transcripts generated in vivo suggests that the tyramine-induced mRNA starts at a site 62 bases upstream from the ATG initiation codon of the maoC gene. In the putative promoter region, a high degree of similarity to the consensus sequence for the binding site of cyclic AMP receptor protein was found. Thus, the mao region is composed of two cistrons, and the mao operon is regulated by monoamine compounds, glucose, and ammonium ions.