Sitaram N, Chatterji D
FEBS Lett. 1985 Mar 11;182(1):77-80. doi: 10.1016/0014-5793(85)81157-1.
The interaction of bovine seminalplasmin and rifampicin with E. coli RNA polymerase was studied using fluorescence spectroscopy. Both seminalplasmin and rifampicin are known to be the inhibitors for the initiation of RNA synthesis in E. coli. Rifampicin quenced the intrinsic fluorescence of RNA polymerase and seminalplasmin when excited at 280 nm. However, excess of seminalplasmin reversed the quenching of RNA polymerase fluorescence by rifampicin. Upon addition of rifampicin to the seminalplasmin-RNA polymerase complex, no change in fluorescence spectrum was observed. It appeared that although rifampicin could form complexes with RNA polymerase and seminalplasmin alone, no binding domain was available for rifampicin in the RNA polymerase-seminalplasmin complex. These observations are discussed in the light of the 'initiation site' of E. coli RNA polymerase.
利用荧光光谱法研究了牛精浆纤溶酶和利福平与大肠杆菌RNA聚合酶的相互作用。已知精浆纤溶酶和利福平都是大肠杆菌中RNA合成起始的抑制剂。当在280nm激发时，利福平使RNA聚合酶和精浆纤溶酶的固有荧光发生猝灭。然而，过量的精浆纤溶酶可逆转利福平对RNA聚合酶荧光的猝灭作用。向精浆纤溶酶-RNA聚合酶复合物中加入利福平后，未观察到荧光光谱的变化。似乎尽管利福平可单独与RNA聚合酶和精浆纤溶酶形成复合物，但在RNA聚合酶-精浆纤溶酶复合物中没有可供利福平结合的结构域。根据大肠杆菌RNA聚合酶的“起始位点”对这些观察结果进行了讨论。
