Department of Food, Agricultural and Biological Engineering, The Ohio State University, 590 Woody Hayes Drive, Columbus, Ohio 43210, USA.
Phys Chem Chem Phys. 2021 Jul 7;23(26):14422-14432. doi: 10.1039/d0cp05950a.
Experimental studies relevant to the nonthermal effects of electric fields on biological systems are emerging. However, these effects are poorly understood at the molecular level. The present study investigates pectin methylesterase, a cell wall modifying enzyme in plants, exposed to various electric field strengths. Molecular dynamics (MD) of the enzyme were studied with and without (thermal-only) electric field applications. The measurements were interpreted on the basis of equivalent energy input to gain insights into the effect of electric field treatment time at a constant temperature (50 °C). Results reveal that electric fields exert nonthermal effects on both local and global protein structure. In 1 μs simulations, the results show significant (P ≤ 0.05) shrinkage of the catalytic domain and shortening of enzyme-water hydrogen bond lifetime by a 50 V cm-1 electric field. Unwinding of the helical segments, altered intra- and intermolecular hydrogen bond patterns, and increased hydration are also caused by the 50 V cm-1 electric field. This study serves to understand the electric field influence on the functional role of proteins.
正在出现与电场对生物系统的非热效应相关的实验研究。然而，这些效应在分子水平上还没有被很好地理解。本研究调查了果胶甲酯酶，一种植物细胞壁修饰酶，暴露于不同的电场强度下。用和不用（仅热）电场应用对酶进行了分子动力学（MD）研究。根据等效能量输入进行测量解释，以深入了解在恒定温度（50°C）下电场处理时间的影响。结果表明，电场对局部和整体蛋白质结构都有非热效应。在 1 μs 的模拟中，结果表明 50 V cm-1 的电场会导致催化域显著（P ≤ 0.05）收缩，酶-水氢键的寿命缩短。50 V cm-1 的电场还会导致螺旋片段展开、改变分子内和分子间氢键模式以及增加水合作用。这项研究有助于了解电场对蛋白质功能作用的影响。
