9VCB

Cryo-EM structure of Shewanella putrefaciens ComEC in complex with ssDNA

9VCB の概要

• エントリーDOI: 10.2210/pdb9vcb/pdb
• 関連するPDBエントリー: 9VC6 9VC9 9VCF
• EMDBエントリー: 64951
• 分子名称: DNA internalization-related competence protein ComEC/Rec2, DNA (30-MER), ZINC ION (3 entities in total)
• 機能のキーワード: competence, dna channel, membrane protein, hydrolase
• 由来する生物種: Shewanella putrefaciens; 詳細
• タンパク質・核酸の鎖数: 2
• 化学式量合計: 98437.87

構造登録者

Hirano, H.,Nureki, O. (登録日: 2025-06-05, 公開日: 2026-04-29)

主引用文献

Hirano, H.,Tsuji, N.,Chiba, S.,Nureki, O.
Structural basis for DNA processing and membrane translocation by ComEC in natural transformation.
Science, 392:311-316, 2026

PubMed Abstract: Natural transformation is one of the major pathways of horizontal gene transfer in bacteria, enabling the acquisition of extracellular DNA and its integration into the host genome. ComEC is a membrane protein responsible for DNA translocation in this process, yet its precise function and structure have remained elusive. Here, we report cryo-electron microscopy structures of ComEC in DNA-free, single-stranded DNA (ssDNA)-bound, and double-stranded DNA (dsDNA)-bound forms, together with biochemical analyses. These structures reveal that ComEC cleaves one strand of dsDNA at its extracellular domain and guides the remaining strand into a positively charged pore formed within the membrane domain. These findings provide a structural basis for the long-hypothesized roles of ComEC in both DNA processing and translocation across the inner membrane during natural transformation.

PubMed: 41990170
DOI: 10.1126/science.aea3485

実験手法

ELECTRON MICROSCOPY (2.82 Å)