Deciphering the kinetic mechanism of spontaneous self-assembly of icosahedral capsids.
Self-assembly of viral proteins into icosahedral capsids is an interesting yet poorly understood phenomenon of which elucidation may aid the exploration of beneficial applications of capsids in materials science and medicine. Using molecular dynamics simulations of coarse-grained models for capsid proteins, we show that the competition between the formation of full capsids and nonidealized structures is strongly dependent upon the protein concentration and temperature, occurring kinetically as a cascade of elementary reactions in which free monomers are added to the growing oligomers on a downhill free-energy landscape. However, the insertion of the final subunits is the rate-limiting, energetically unfavorable step in viral capsid assembly. A phase diagram has been constructed to show the regions where capsids or nonidealized structures are stable at each concentration and temperature. We anticipate that our findings will provide guidance in identifying suitable conditions required for in vitro viral capsid assembly experiments.
Nguyen
Hung D
HD
Department of Molecular Biology, TPC6, 10550 North Torrey Pines Road, La Jolla, California 92037, USA.
Reddy
Vijay S
VS
Brooks
Charles L
CL
D002213:Capsid / Q000737:chemistry* / Q000502:physiology / Q000648:ultrastructure; D004355:Drug Stability; D007700:Kinetics; D008854:Microscopy, Electron; D008958:Models, Molecular; D046912:Multiprotein Complexes; D036103:Nanotechnology; D013816:Thermodynamics; D019065:Virus Assembly
D046912:Multiprotein Complexes