Dimerization of\nthe Aβ<sub>42</sub> under the\nInfluence of the Gold Nanoparticle: A REMD Study

Advances in Alzheimer’s disease (AD) are related\nto the\noligomerization of Amyloid β (Aβ) peptides. Therefore,\nalteration of the process can prevent AD. We investigated the Aβ<sub>42</sub> dimerization under the effects of gold nanoparticles using\ntemperature replica-exchange molecular dynamics (REMD) simulations.\nThe structural change of dimers in the presence and absence of the\ngold nanoparticle, Au<sub>55</sub>, was monitored over stable intervals.\nPhysical insights into the oligomerization of Aβ were thus clarified.\nThe computed metrics indicate that Au<sub>55</sub> affects the progress\nof oligomerization. Specifically, the presence of the gold nanoparticle\nsignificantly modifies the structure of dimeric Aβ<sub>42</sub>. The β-content experienced a substantial decrease with the\ninduction of Au<sub>55</sub>. The turn and coil-contents are also\ndecreased under the effects of the gold nanoparticle. However, the\nα-content of the dimer exhibited a rigid increase. The influence\nof gold nanoparticles on the dimeric Aβ<sub>42</sub> differs\nsignificantly from that of silver nanoparticles, which reduce β-content\nbut increase coil-, turn-, and α-contents. The nature of inhibition\nwill be discussed, in which the vdW interaction plays a driving force\nfor the interaction between the Aβ<sub>42</sub> dimer and the\ngold nanoparticle.