Severinov K, Fenyö D, Severinova E, Mustaev A, Chait B T, Goldfarb A, Darst S A
Public Health Research Institute, New York, New York 10016.
J Biol Chem. 1994 Aug 19;269(33):20826-8.
Ribonucleotide analogs bound in the initiating site of Escherichia coli RNA polymerase holoenzyme in open promoter complexes were cross-linked to the beta and sigma 70 subunits. Using limited proteolysis and chemical degradation, the cross-link site in sigma 70 was mapped to a segment between amino acids Glu508 and Met561 containing the C-terminal part of conserved region 3. This result, when reconciled with genetic data on the interaction of sigma 70 conserved regions 2 and 4 with the -10 and -35 promoter regions, respectively, allows us to model the orientation of the sigma 70 subunit domains within the open promoter complex.
在开放启动子复合物中与大肠杆菌RNA聚合酶全酶起始位点结合的核糖核苷酸类似物与β亚基和σ70亚基发生了交联。通过有限蛋白酶解和化学降解，将σ70中的交联位点定位到了氨基酸Glu508和Met561之间的一段区域，该区域包含保守区域3的C末端部分。当这一结果与关于σ70保守区域2和4分别与-10和-35启动子区域相互作用的遗传数据相结合时，使我们能够构建开放启动子复合物中σ70亚基结构域的取向模型。
