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Generation and Assembly of Virus-Specific Nucleocapsids of the Respiratory Syncytial Virus
Published on: July 27, 2021
Orientational phase transitions and the assembly of viral capsids
Sanjay Dharmavaram1, Fangming Xie2, William Klug3
1Department of Physics and Astronomy, University of California, Los Angeles, California 90095, USA.
Abstract:
We present a Landau theory for large-l orientational phase transitions and apply it to the assembly of icosahedral viral capsids. The theory predicts two distinct types of ordering transitions. Transitions dominated by the l=6,10,12, and 18 icosahedral spherical harmonics resemble robust first-order phase transitions that are not significantly affected by chirality. The remaining transitions depend essentially on including mixed l states denoted as l=15+16 corresponding to a mixture of l=15 and l=16 spherical harmonics. The l=15+16 transition is either continuous or weakly first-order and it is strongly influenced by chirality, which suppresses spontaneous chiral symmetry breaking. The icosahedral state is in close competition with states that have tetrahedral, D_{5}, and octahedral symmetries. We present a group-theoretic method to analyze the competition between the different symmetries. The theory is applied to a variety of viral shells.
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