Effects of PHB and SFC charge models on the side chain-side chain interactions in the simulation of β-hairpins

• Polarizable force fields PHB and SFC were applied to simulate two β-hairpins. • Their effects on side chain-side chain interaction were examined. • Future force fields require consideration of both backbone H bonds and side chains. In view of the recent development of polarizable force fields namely polarizable hydrogen bond (PHB) and semi-fluctuating charge (SFC) developed by Zhang's group, we would like to explore the effects of these two models on side chain-side chain interactions through the simulation of two β-hairpins. The results show that the PHB model strengthens but the SFC model weakens side chain-side chain interactions in our studies. Through this study, we aim to have a more comprehensive understanding of these two models which only focus on the charge updating of backbone atoms.