Organization of open complexes at Escherichia coli promoters -: Location of promoter DNA sites close to region 2.5 of the σ70 subunit of RNA polymerase
Organization of open complexes at Escherichia coli promoters -: Location of promoter DNA sites close to region 2.5 of the σ70 subunit of RNA polymerase
复制标题
DOI：
10.1074/jbc.274.4.2263
复制
发表时间：
1999-01-22
影响因子：
4.8
通讯作者：
Minchin, SD
中科院分区：
文献类型：
--
作者：
Bown, JA;Owens, JT;Minchin, SD
A cysteine-tethered DNA cleavage agent has been used to locate the position of region 2.5 of sigma(70) in transcriptionally competent complexes between Escherichia coli RNA polymerase and promoters. In this study we have engineered sigma(70) to introduce a unique cysteine residue at a number of positions in region 2.5. Mutant proteins were purified, and in each case, the single cysteine residue used as the target for covalent coupling of the DNA cleavage agent p-bromoacetamidobenzyl-EDTA . Fe (FeBABE). RNA polymerase core reconstituted with tagged a derivatives was shown to be transcriptionally active. Hydroxyl radical-based DNA cleavage mediated by tethered FeBABE was observed for each derivative of RNA polymerase in the open complex. Our results show that region 2.5 is in close proximity to promoter DNA just upstream of the -10 hexamer. This positioning is independent of promoter sequence. A model for the interaction of this region of a with promoter DNA is discussed.
