Faculty of Chemistry and Chemical Engineering, University of Maribor, Smetanova ulica 17, Maribor SI-2000, Slovenia.
Institute of Molecular Modeling and Simulation, University of Natural Resources and Life Sciences, Muthgasse 18, Vienna 1190, Austria.
J Chem Inf Model. 2024 Mar 25;64(6):2077-2083. doi: 10.1021/acs.jcim.3c01937. Epub 2024 Mar 13.
The impact of microwave (MW) irradiation on protein folding, potentially inciting misfolding, was investigated by employing molecular dynamics (MD) simulations. Twenty-nine proteins were subjected to MD simulations under equilibrium (300 K) and MW conditions, where the rotational temperature was elevated to 700 K. The utilized replacement model captures the microwave effects of δ- and γ-relaxation processes (frequency range of ∼300 MHz to ∼20 GHz). The results disclosed that MW heating incited a shift toward more compact protein conformations, as indicated by decreased root-mean-square deviations, root-mean-square fluctuations, head-to-tail distances, and radii of gyration. This compaction was attributed to the intensification of intramolecular electrostatic interactions and hydrogen bonds within the protein caused by MW-destabilized hydrogen bonds between the protein and solvent. The solvent-accessible surface area (SASA), particularly that of polar amino-acid residues, shrank under MW conditions, corresponding to a reduced polarity of the water solvent. However, MW irradiation produced no significant alterations in protein secondary structures; hence, MW heating was observed to primarily affect the protein tertiary structures.
采用分子动力学（MD）模拟研究了微波（MW）辐照对蛋白质折叠的影响，可能会引发错误折叠。对 29 种蛋白质进行了 MD 模拟，分别在平衡（300K）和 MW 条件下进行，其中旋转温度升高到 700K。所采用的替换模型捕获了微波 δ-和 γ-弛豫过程的影响（频率范围约为 300MHz 至 20GHz）。结果表明，MW 加热会导致蛋白质构象向更紧凑的方向转变，这表现为均方根偏差、均方根波动、头尾距离和回转半径的降低。这种紧凑化归因于 MW 破坏的氢键导致蛋白质和溶剂之间的氢键不稳定，从而加剧了蛋白质内部的分子间静电相互作用和氢键。溶剂可及表面积（SASA），特别是极性氨基酸残基的 SASA，在 MW 条件下收缩，对应于水溶剂极性的降低。然而，MW 辐照对蛋白质二级结构没有产生显著影响；因此，MW 加热主要影响蛋白质三级结构。
