In E. coli dihydrofolate reductase, unusual conformational motions of a functional M20 loop that interacts with substrate and coenzyme have been construed as evidence for dynamical effects in enzyme catalysis. By computing this loop’s conformational free energies in the apoenzyme, we show that it is sensitive to the treatment of long-range electrostatic interactions and the solvation box size in modeling/simulations. These results provide important guidelines for computing reaction/binding free energy profiles of proteins with functional loops.

中文翻译：

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功能性环构型对远距离静电的敏感性：大肠杆菌二氢叶酸还原酶中M20环动力学的含义。

在大肠杆菌二氢叶酸还原酶中，与底物和辅酶相互作用的功能性M20环的异常构象运动被认为是酶催化动力学作用的证据。通过计算该环在脱辅酶中的构象自由能，我们表明它对远程静电相互作用的处理和建模/模拟中的溶剂化盒尺寸敏感。这些结果为计算具有功能环的蛋白质的反应/结合自由能谱提供了重要指导。