Primary structure of the essential replicon of the plasmid pSC101.
Primary structure of the essential replicon of the plasmid pSC101.
复制标题
质粒 pSC101 必需复制子的一级结构。
DOI：
10.1073/pnas.80.21.6557
复制
发表时间：
1983
影响因子：
11.1
通讯作者：
Bastia,D
中科院分区：
文献类型：
--
作者：
Vocke,C;Bastia,D
低拷贝数质粒pSC 101的复制子必须需要大肠杆菌的dnaA起始蛋白以及质粒编码的起始蛋白。我们已经确定了质粒编码的启动子的顺反子的DNA序列分析。启动子顺反子与大肠杆菌lacZ基因的融合。大肠杆菌产生约等于150千道尔顿的融合蛋白，从而证实通过DNA序列分析检测的开放阅读框实际上编码37.5千道尔顿的蛋白。从质粒起始物的COOH末端缺失26个氨基酸残基，消除了从pSC 101起始的自主复制。通过体外缺失分析，我们已经表明，虽然从启动顺反子下游的序列是重复的，最大的400个碱基对直接上游的NH 2-末端区域的启动子是必要的质粒复制。这些上游序列含有一个富含A + T的区域和三个21个碱基对序列的串联重复序列;这些特征是其他复制起点的特征。
The replicon of the low copy number plasmid pSC101 has an obligatory requirement for the dnaA initiator protein of Escherichia coli as well as a plasmid-encoded initiator protein. We have identified the cistron of the plasmid-encoded initiator by DNA sequence analysis. Fusion of the initiator cistron with the lacZ gene of E. coli yielded a fusion protein of approximately equal to 150 kilodaltons, thus confirming that the open reading frame detected by DNA sequence analysis actually encoded a 37.5-kilodalton protein. Deletion of 26 amino acid residues from the COOH terminus of the plasmid initiator abolished autonomous replication from pSC101 origin. By in vitro deletion analysis we have shown that, although sequences downstream from the initiator cistron are dispensable, a maximum of 400 base pairs immediately upstream from the NH2-terminal region of the initiator is necessary for plasmid replication. These upstream sequences contain an A + T-rich region and three tandem repeats of a 21-base pair sequence; these features are characteristics of other replication origins.