title: Molecular architecture of the prolate head of bacteriophage T4.
abstract: The head of bacteriophage T4 is a prolate icosahedron with one unique portal vertex to which the phage tail is attached. The three-dimensional structure of mature bacteriophage T4 head has been determined to 22-A resolution by using cryo-electron microscopy. The T4 capsid has a hexagonal surface lattice characterized by the triangulation numbers T(end) = 13 laevo for the icosahedral caps and T(mid) = 20 for the midsection. Hexamers of the major capsid protein gene product (gp)23* and pentamers of the vertex protein gp24*, as well as the outer surface proteins highly antigenic outer capsid protein (hoc) and small outer capsid protein (soc), are clearly evident in the reconstruction. The size and shape of the gp23* hexamers are similar to the major capsid protein organization of bacteriophage HK97. The binding sites and shape of the hoc and soc proteins have been established by analysis of the soc(-) and hoc(-)soc(-) T4 structures.
authors.affiliation: Department of Biological Sciences, Purdue University, 915 West State Street, West Lafayette, IN 47907-2054, USA.
authors.forename: Andrei
authors.initials: A
authors.lastname: Fokine
authors.forename: Paul R
authors.initials: PR
authors.lastname: Chipman
authors.forename: Petr G
authors.initials: PG
authors.lastname: Leiman
authors.forename: Vadim V
authors.initials: VV
authors.lastname: Mesyanzhinov
authors.forename: Venigalla B
authors.initials: VB
authors.lastname: Rao
authors.forename: Michael G
authors.initials: MG
authors.lastname: Rossmann
mesh_terms: D017122:Bacteriophage T4 / Q000737:chemistry* / Q000648:ultrastructure; D020285:Cryoelectron Microscopy