9K2V

Cyanophage A4 pre-ejectosome

9K2V の概要

• エントリーDOI: 10.2210/pdb9k2v/pdb
• EMDBエントリー: 61998
• 分子名称: Portal protein, Internal virion protein, Internal protein, ... (4 entities in total)
• 機能のキーワード: cyanophage, virus, ejectosome, viral protein
• 由来する生物種: Anabaena phage A-4L; 詳細
• タンパク質・核酸の鎖数: 30
• 化学式量合計: 2315258.50

構造登録者

Hou, P.,Li, Q.,Zhou, C.Z. (登録日: 2024-10-18, 公開日: 2025-04-09, 最終更新日: 2025-07-02)

主引用文献

Hou, P.,Zhou, R.Q.,Jiang, Y.L.,Yu, R.C.,Du, K.,Gan, N.,Ke, F.,Zhang, Q.Y.,Li, Q.,Zhou, C.Z.
Cryo-EM structure of cyanopodophage A4 reveals a pentameric pre-ejectosome in the double-stabilized capsid.
Proc.Natl.Acad.Sci.USA, 122:e2423403122-e2423403122, 2025

PubMed Abstract: Upon infection, the podophages usually eject a couple of proteins from the capsid to form a transmembrane ejectosome on the host cell membrane that facilitates the ejection of viral genome. However, it remains unclear how these proteins of pre-ejectosome are finely assembled at the center of highly packaged genome. Here, we report the intact structure of cyanopodophage A4, which consists of a capsid stabilized by two types of cement proteins and a short tail attached with six tail fibers. Notably, we find a pentameric pre-ejectosome at the core of capsid, which is composed of four ejection proteins wrapped into a coaxial cylinder of triple layers. Moreover, a segment of genomic DNA runs along the positively charged circular cleft formed by two ejection proteins. Based on the mortise-and-tenon architecture of pre-ejectosome in combination with previous studies, we propose a putative DNA packaging process and ejection mechanism for podophages. These findings largely enrich our knowledge on the assembly mechanism of podophages, which might facilitate the application of A4 as a chassis cyanophage in synthetic biology.

PubMed: 40163721
DOI: 10.1073/pnas.2423403122

実験手法

ELECTRON MICROSCOPY (3.4 Å)