2FT1

Bacteriophage HK97 Head II

Summary for 2FT1

• Entry DOI: 10.2210/pdb2ft1/pdb
• Related: 1OHG 2FRP 2FS3 2FSY 2FTE
• Descriptor: major capsid protein (1 entity in total)
• Functional Keywords: bacteriophage, hk97, capsid protein, mature capsid, icosahedral virus, virus
• Biological source: Enterobacteria phage HK97
• Cellular location: Virion: P49861
• Total number of polymer chains: 7
• Total formula weight: 215632.25

Authors

Gan, L.,Speir, J.A.,Conway, J.F.,Lander, G.,Cheng, N.,Firek, B.A.,Hendrix, R.W.,Duda, R.L.,Liljas, L.,Johnson, J.E. (deposition date: 2006-01-23, release date: 2006-02-07, Last modification date: 2023-09-20)

Primary citation

Gan, L.,Speir, J.A.,Conway, J.F.,Lander, G.,Cheng, N.,Firek, B.A.,Hendrix, R.W.,Duda, R.L.,Liljas, L.,Johnson, J.E.
Capsid Conformational Sampling in HK97 Maturation Visualized by X-Ray Crystallography and Cryo-EM.
Structure, 14:1655-1665, 2006

PubMed Abstract: Maturation of the bacteriophage HK97 capsid from a precursor (Prohead II) to the mature state (Head II) involves a 60 A radial expansion. The mature particle is formed by 420 copies of the major capsid protein organized on a T = 7 laevo lattice with each subunit covalently crosslinked to two neighbors. Well-characterized pH 4 expansion intermediates make HK97 valuable for investigating quaternary structural dynamics. Here, we use X-ray crystallography and cryo-EM to demonstrate that in the final transition in maturation (requiring neutral pH), pentons in Expansion Intermediate IV (EI-IV) reversibly sample 14 A translations and 6 degrees rotations relative to a fixed hexon lattice. The limit of this trajectory corresponds to the Head II conformation that is secured at this extent only by the formation of the final class of covalent crosslinks. Mutants that cannot crosslink or EI-IV particles that have been rendered incapable of forming the final crosslink remain in the EI-IV state.

PubMed: 17098191
DOI: 10.1016/j.str.2006.09.006

Experimental method

X-RAY DIFFRACTION (3.9 Å)