Constant pH molecular dynamics of porcine circovirus 2 capsid protein reveals a mechanism for capsid assembly.

ABSTRACT: Spatiotemporal regulation of viral capsid assembly ensures the selection of the viral genome for encapsidation. The porcine circovirus 2 is the smallest autonomously replicating pathogenic virus, yet how PCV2 capsid assembly is regulated to occur within the nucleus remains unknown. We report that pure PCV2 capsid proteins, in the absence of nucleic acids, require acidic conditions to assemble into empty capsids in vitro. By employing constant pH replica exchange molecular dynamics, we unveil the atomistic mechanism of pH-dependency for capsid assembly. The results show that an appropriate protonation configuration for a cluster of acidic amino acids is necessary to appropriately position the GH-loop for driving the capsid assembly. We demonstrate that assembly is prohibited at neutr

SUBMITTER: Tarasova E 

PROVIDER: S-EPMC8705882 | biostudies-literature | 2021 Nov

REPOSITORIES: biostudies-literature