5VF3

Bacteriophage T4 isometric capsid

Summary for 5VF3

• Entry DOI: 10.2210/pdb5vf3/pdb
• EMDB information: 8661
• Descriptor: Capsid vertex protein gp24, Major capsid protein, Small outer capsid protein, ... (5 entities in total)
• Functional Keywords: bacteriophage t4, isometric head, virus capsid assembly, triangulation numbers, size-determining mutations, capsid stabilization, capsid decoration proteins, virus
• Biological source: Enterobacteria phage T4; More
• Total number of polymer chains: 26
• Total formula weight: 772232.11

Authors

Chen, Z.,Sun, L.,Zhang, Z.,Fokine, A.,Padilla-Sanchez, V.,Hanein, D.,Jiang, W.,Rossmann, M.G.,Rao, V.B. (deposition date: 2017-04-06, release date: 2017-09-13, Last modification date: 2024-03-13)

Primary citation

Chen, Z.,Sun, L.,Zhang, Z.,Fokine, A.,Padilla-Sanchez, V.,Hanein, D.,Jiang, W.,Rossmann, M.G.,Rao, V.B.
Cryo-EM structure of the bacteriophage T4 isometric head at 3.3- angstrom resolution and its relevance to the assembly of icosahedral viruses.
Proc. Natl. Acad. Sci. U.S.A., 114:E8184-E8193, 2017

PubMed Abstract: The 3.3-Å cryo-EM structure of the 860-Å-diameter isometric mutant bacteriophage T4 capsid has been determined. WT T4 has a prolate capsid characterized by triangulation numbers (T numbers) T = 13 for end caps and T = 20 for midsection. A mutation in the major capsid protein, gp23, produced T=13 icosahedral capsids. The capsid is stabilized by 660 copies of the outer capsid protein, Soc, which clamp adjacent gp23 hexamers. The occupancies of Soc molecules are proportional to the size of the angle between the planes of adjacent hexameric capsomers. The angle between adjacent hexameric capsomers is greatest around the fivefold vertices, where there is the largest deviation from a planar hexagonal array. Thus, the Soc molecules reinforce the structure where there is the greatest strain in the gp23 hexagonal lattice. Mutations that change the angles between adjacent capsomers affect the positions of the pentameric vertices, resulting in different triangulation numbers in bacteriophage T4. The analysis of the T4 mutant head assembly gives guidance to how other icosahedral viruses reproducibly assemble into capsids with a predetermined T number, although the influence of scaffolding proteins is also important.

PubMed: 28893988
DOI: 10.1073/pnas.1708483114

Experimental method

ELECTRON MICROSCOPY (3.3 Å)