Xie, YuxinLi, Nan K.Singh, AbhishekDeshmukh, Sanket A.Yingling, Yaroslava G.2022-03-282022-03-282022-03-18Xie, Y.; Li, N.K.; Singh, A.; Deshmukh, S.A.; Yingling, Y.G. A Comparison between the Lower Critical Solution Temperature Behavior of Polymers and Biomacromolecules. Physchem 2022, 2, 52-71.http://hdl.handle.net/10919/109456All-atom molecular dynamics (MD) simulations are employed to compare the lower critical solution temperature (LCST) behaviors of poly(N-isopropylacrylamide) (PNIPAM) and elastin-like polypeptides (ELPs) with the canonical Val-Pro-Gly-Val-Gly ((VPGVG)<i>_n</i>) sequence over a range of temperatures from 280 K to 380 K. Our simulations suggest that the structure of proximal water dictates the conformation of both the (VPGVG)<i>_n</i> ELPs and PNIPAM chains. Specifically, the LCST transition in ELPs can be attributed to a combination of thermal disruption of the network of the proximal water near both hydrophilic and hydrophobic groups in the backbone and side-chain of (VPGVG)<i>_n</i>, resulting in a reduction in solvent accessible surface area (SASA). This is accompanied with an increase in the secondary structure above its LCST. In the case of PNIPAM, the LCST transition is a result of a combination of a reduction in the hydrophobic SASA primarily due to the contributions of isopropyl side-chain and less to the backbone and the formation of intra-chain hydrogen bonds between the amide groups on the side-chain above its LCST.application/pdfenCreative Commons Attribution 4.0 Internationalall-atom molecular dynamics simulationslower critical solution temperaturepolymers and biopolymersArticle - Refereed2022-03-24https://doi.org/10.3390/physchem2010005