Major capsid protein self-assembles to form an icosahedral capsid with a pseudo T=25 symmetry, about 66 nm in diameter, and consisting of 240 capsid proteins trimers. The capsid encapsulates an inner membrane and the genomic dsDNA genome. The major coat protein P3 and two assembly factors (P10 and P17) are needed during the assembly of the virus particle inside the host cell, when the capsid protein multimers are capable of enclosing the host-derived membrane, containing the virus-encoded membrane-associated proteins. Homotrimer. Icosahedral capsid structure Icosahedral capsid structure Icosahedral capsid structure of SUS607 mutant Icosahedral virus capsid P3-shell structure Icosahedral capsid structure of SUS1 mutant