Evidence for protein misfolding in the presence of nanoplastics

Abstract

The possible effect of plastic nanoparticles of waste origin on biological systems is still unclear and could pose a severe threat. Model studies at the molecular level are urgently needed in order to help reveal the interplay between these particles and biological systems, and thereby to indicate the direction of further research. In the present study, simulated annealing molecular dynamics is adjusted and applied to generate an array of conformations for a sample peptide oligoalanine possibly binding to polyethylene and nylon 6,6 nanoplastics. The resulting structures, with a diameter of up to 5 nm, were investigated with the aid of static quantum chemical calculations. The obtained data unequivocally show that both plastic nanoparticles influence the relative stability of α-helix, β-hairpin, and other conformations strongly. Polyethylene nanoparticle increases the stability of the helical foldamer. Nylon 6,6 nanoplastic offers strong plastic-peptide interactions on its surface, making the unfolding of the peptide thermodynamically highly favorable. These results further underscore that nanoplastics can do significant molecular-level damage to living organisms via facilitating the misfolding and denaturation of proteins. Furthermore, it is apparent that plastics can have very different effects on living matter depending upon their composition, and hence experiments with any single kind of plastics (eg, polystyrene) should not be considered generally valid for all nanoplastics.

Ionic Liquids as Extractants for Nanoplastics

“…[16] They can alter biologically relevant properties of lipid bilayers (and thereby cell membranes), [38,39] while our and other research groups have also shown their effects on proteins as well. [30][31][32][33] For this reason, it is paramount to establish strategies for the accurate measurement of PNP concentrations, and eventually for the removal of these particles from the environment and from consumption products. [40] Nguyen et al recently gave an overview addressing the challenges related to the separation of small plastic particles and their analysis in complex samples.…”

“…There is an increasing number of studies showing potentially adverse effects of nanoplastics, and the findings are rather alarming . It was recently shown that nanoplastics can enter individual cells .…”

“…It was recently shown that nanoplastics can enter individual cells . They can alter biologically relevant properties of lipid bilayers (and thereby cell membranes), while our and other research groups have also shown their effects on proteins as well . For this reason, it is paramount to establish strategies for the accurate measurement of PNP concentrations, and eventually for the removal of these particles from the environment and from consumption products .…”

“…[27,28] There is an increasing number of studies showing potentially adverse effects of nanoplastics, and the findings are rather alarming. [16,[29][30][31][32][33][34][35][36][37] It was recently shown that nanoplastics can enter individual cells. [16] They can alter biologically relevant properties of lipid bilayers (and thereby cell membranes), [38,39] while our and other research groups have also shown their effects on proteins as well.…”

Germany’s Future in Theoretical and Computational Chemistry: a Special Issue Celebrating DEAL

“…For example, Götze et al [14] present a new QM/MM software interface (gmx2qmmm), that offers novel ways to treat the QM/MM boundary region, showing how it fares for flexible amino‐acid conformations and the calculation of UV/vis spectra. Finally, Oldamur Hollóczki [15] investigates the stability of oligoalanines in the presence of plastic nanoparticles through simulated annealing and semi‐empirical approaches for the conformational search and stability assessment, respectively.…”