An isothermal titration calorimetry study of phytate binding to lysozyme
An isothermal titration calorimetry study of phytate binding to lysozyme
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DOI：
10.1007/s10973-016-5487-6
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发表时间：
2017-02-01
影响因子：
4.4
通讯作者：
Falconer, Robert J.
中科院分区：
文献类型：
--
作者：
Darby, Samuel J.;Platts, Lauren;Falconer, Robert J.
等温滴定量热法（ITC）用于检测植酸与溶菌酶蛋白的结合。这种结合作用是由带正电荷的蛋白质和带负电荷的植酸之间的静电作用驱动的。当两个植酸分子与蛋白质结合时，蛋白质上的电荷被中和，不再发生进一步的结合。结合的化学计量法证明植酸-同工酶复合物的形成与温度有关，在较低温度下最为广泛。植酸与溶菌酶结合的初始阶段放热少于后来的注射阶段，在 313 K 时的化学计量为 0.5，这被解释为植酸交联了两个溶菌酶分子，并产生了相应的水置换。ITC 可以作为一种有价值的体外检测方法，用于了解单胃动物胃中通常发生的结合相互作用和复合物形成，以及饮用水温度对植酸盐-蛋白质相互作用程度的相关性。此外，还讨论了从合作性角度解释 ITC 数据的问题。
Isothermal titration calorimetry (ITC) was used to detect phytate binding to the protein lysozyme. This binding interaction was driven by electrostatic interaction between the positively charged protein and negatively charged phytate. When two phytate molecules bind to the protein, the charge on the protein is neutralised and no further binding occurs. The stoichiometry of binding provided evidence of phytate-lysozyme complex formation that was temperature dependent, being most extensive at lower temperatures. The initial stage of phytate binding to lysozyme was less exothermic than later injections and had a stoichiometry of 0.5 at 313 K, which was interpreted as phytate crosslinking two lysozyme molecules with corresponding water displacement. ITC could make a valuable in vitro assay to understanding binding interactions and complex formation that normally occur in the stomach of monogastric animals and the relevance of drinking water temperature on the extent of phytate-protein interaction. Interpretation of ITC data in terms of cooperativity is also discussed.