Fujita N, Ishihama A, Nagasawa Y, Ueda S
Department of Molecular Genetics, National Institute of Genetics, Shizuoka, Japan.
Mol Gen Genet. 1987 Nov;210(1):5-9. doi: 10.1007/BF00337751.
Antibodies were raised against a synthetic tetradecameric peptide with an amino acid sequence, DLIQEGNIGLMKAV, which corresponds to the most highly conserved region of bacterial RNA polymerase sigma factors. In a Western-blot analysis of total Escherichia coli proteins, the antiserum reacted specifically with at least three proteins with apparent molecular weights of 75 kDa, 27 kDa and 23 kDa, in addition to the known sigma factors (sigma 70 and sigma 32). The majorities of sigma 70 and sigma 32 were recovered as associated forms with the RNA polymerase on glycerol gradient centrifugation, while the other cross-reacting proteins were not. Unambiguous evidence was obtained which indicated that the intracellular level of sigma 32 increased rapidly upon heat-shock, at least in the strain containing high copy numbers of the rpoH gene.
针对一种合成的十四聚体肽产生了抗体，该肽的氨基酸序列为DLIQEGNIGLMKAV，它对应于细菌RNA聚合酶σ因子的最高度保守区域。在对大肠杆菌总蛋白进行的蛋白质印迹分析中，除了已知的σ因子（σ70和σ32）外，抗血清还与至少三种表观分子量分别为75 kDa、27 kDa和23 kDa的蛋白质发生特异性反应。在甘油梯度离心中，大多数σ70和σ32以与RNA聚合酶相关的形式被回收，而其他交叉反应蛋白则没有。获得了明确的证据，表明至少在含有高拷贝数rpoH基因的菌株中，热休克后σ32的细胞内水平迅速增加。
