Impact of Surface Charge Density and Motor Force Upon Polyelectrolyte Packaging in Viral Capsids
نویسندگان
چکیده
By means of Langevin molecular dynamics simulations, we study the packaging dynamics of flexible and semiflexible polyelectrolytes in spherical cavities that resemble viral capsids. We employ a coarse-grained model of the polymer– capsid complex that allows us to perform simulations of a 900mer and investigate the influence of surface charges inside the capsid and an additional motor force, acting on the polymer in the portal region of the cavity, on the packaging process. Our results indicate that it is most efficient if surface charges are present that initially promote the formation of an ordered surface layer inside the capsid. Once these charges are screened, the motor force pulls in the remaining part of the chain. Additionally, the simulations also demonstrate that the packaging dynamics depends on the counterion valence. VC 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2016, 54, 1054–1065
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