Stability of SIV gp32 fusion-peptide single-layer protofibrils as monitored by molecular-dynamics simulations

Modeling the mechanisms of protofibril twisting: Molecular-dynamics simulations of simian viral peptide aggregates show that β sheets of 10 to 30 chains form left-handed helical ribbons with saddlelike curvature (see picture). These structures are highly dynamic, with oscillations around an average twist angle of 9-10°, and a pitch of 15-20 nm, depending on β-sheet length. The peptides studied are key to viral entry into host cells. © 2005 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.