5JJ1

Structure of the Immature Procapsid Conformation of P22 Portal Protein

5JJ1 の概要

• エントリーDOI: 10.2210/pdb5jj1/pdb
• 関連するPDBエントリー: 3LJ4 3LJ5 4V4K 5JJ3
• 分子名称: Portal protein (1 entity in total)
• 機能のキーワード: portal protein; dodecamer; packaging motor; procapsid, viral protein
• 由来する生物種: Enterobacteria phage P22
• タンパク質・核酸の鎖数: 12
• 化学式量合計: 842909.72

構造登録者

Lokareddy, R.K.,Cingolani, G. (登録日: 2016-04-22, 公開日: 2017-02-08, 最終更新日: 2024-03-06)

主引用文献

Lokareddy, R.K.,Sankhala, R.S.,Roy, A.,Afonine, P.V.,Motwani, T.,Teschke, C.M.,Parent, K.N.,Cingolani, G.
Portal protein functions akin to a DNA-sensor that couples genome-packaging to icosahedral capsid maturation.
Nat Commun, 8:14310-14310, 2017

PubMed Abstract: Tailed bacteriophages and herpesviruses assemble infectious particles via an empty precursor capsid (or 'procapsid') built by multiple copies of coat and scaffolding protein and by one dodecameric portal protein. Genome packaging triggers rearrangement of the coat protein and release of scaffolding protein, resulting in dramatic procapsid lattice expansion. Here, we provide structural evidence that the portal protein of the bacteriophage P22 exists in two distinct dodecameric conformations: an asymmetric assembly in the procapsid (PC-portal) that is competent for high affinity binding to the large terminase packaging protein, and a symmetric ring in the mature virion (MV-portal) that has negligible affinity for the packaging motor. Modelling studies indicate the structure of PC-portal is incompatible with DNA coaxially spooled around the portal vertex, suggesting that newly packaged DNA triggers the switch from PC- to MV-conformation. Thus, we propose the signal for termination of 'Headful Packaging' is a DNA-dependent symmetrization of portal protein.

PubMed: 28134243
DOI: 10.1038/ncomms14310

実験手法

X-RAY DIFFRACTION (3.3 Å)