The effects of salt on the TATA binding protein-DNA interaction from a hyperthermophilic archaeon
The effects of salt on the TATA binding protein-DNA interaction from a hyperthermophilic archaeon
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DOI：
10.1006/jmbi.1998.1743
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发表时间：
1998-05-29
影响因子：
5.6
通讯作者：
Ladbury, JE
中科院分区：
文献类型：
--
作者：
O'Brien, R;DeDecker, B;Ladbury, JE
研究了沃氏火球菌TATA盒结合蛋白（TBP）与含有特异结合位点的寡核苷酸相互作用的热力学。Pw是一种极端嗜热古生物，在高盐和高温条件下生存。可测量的蛋白质-DNA相互作用仅在高盐浓度下发生。在不同浓度（0.8至1.6 M）的一系列盐（氯化钾、磷酸钾、乙酸钾和乙酸钠）下进行等温滴定量热结合研究。在所用的高盐浓度下，所观察到的平衡结合常数随着盐浓度的增加而增加。这是非常不同的效果报告的所有其他蛋白质-DNA的相互作用，已研究在较低的盐浓度。热力学数据表明，在高盐浓度下的蛋白质-DNA相互作用是伴随着大量的水分子从掩埋的疏水表面区域的去除。此外，离子的参与似乎会影响结合，这可以通过蛋白质上的静电负侧叶和带负电荷的DNA之间的界面中的阳离子结合来解释。(C)出版社：Academic Press Limited。
This study investigates the thermodynamics of the interaction of the TATA box binding protein (TBP) from Pyrococcus woesei (Pw) with an oligonucleotide containing a specific binding site. Pw is a hyperthermophilic archeal organism which exists under conditions of high salt and high temperature. A measurable protein-DNA interaction only occurs at high salt concentrations. Isothermal titration calorimetric binding studies were performed under a range of salts (potassium chloride, potassium phosphate, potassium acetate and sodium acetate) at varying concentrations (0.8 to 1.6 M). At the high salt concentrations used the observed equilibrium binding constant increases with increasing salt concentration. This is very different to the effect reported for all other protein-DNA interactions which have been studied at lower salt concentrations. Thermodynamic data suggest that the protein-DNA interaction at high salt concentration is accompanied by the removal of large numbers of water molecules from the buried hydrophobic surface area. In addition, the involvement of ions appears to influence the binding which can be explained by binding of cations in the interface between the electrostatically negative lateral lobes on the protein and the negatively charged DNA. (C) 1998 Academic Press Limited.