9MMU

M5 protein with Factor H 6-7 domain

9MMU の概要

• エントリーDOI: 10.2210/pdb9mmu/pdb
• 分子名称: M protein, serotype 5, Complement factor H (3 entities in total)
• 機能のキーワード: complement evasion, m protein, factor h, immune system
• 由来する生物種: Streptococcus pyogenes str. Manfredo; 詳細
• タンパク質・核酸の鎖数: 8
• 化学式量合計: 97676.91

構造登録者

Kumar, A.,Ghosh, P. (登録日: 2024-12-20, 公開日: 2026-02-04, 最終更新日: 2026-04-22)

主引用文献

Kumar, A.,Wang, K.C.,Ghosh, P.
Structural mechanisms for the recruitment of factor H by Streptococcus pyogenes.
Structure, 2026

PubMed Abstract: The bacterial pathogen Streptococcus pyogenes (Strep A) recruits the complement regulator factor H (FH) to its surface using M proteins and FbaA. However, no conserved FH-binding sequence pattern is evident in these proteins. To address this, we determined the structures of M5 protein, M6 protein, and FbaA fragments complexed with FH domains 6 and 7. M5 and M6 proteins formed dimeric α-helical coiled coils, as expected, while FbaA formed a monomeric three-helix bundle preceded by a loop. Each Strep A protein had a different FH-binding mode, and distinct FH-binding sequence patterns were constructed for each based on substitution mutagenesis. About half of the known 250 Strep A strains were identified to have FH-binding patterns, with the majority due to FbaA as compared to M or M-like Enn proteins. Our structural and functional elucidation of the mechanism of FH recruitment is applicable to the precise investigation of its role in Strep A virulence.

PubMed: 41844154
DOI: 10.1016/j.str.2026.02.010

実験手法

X-RAY DIFFRACTION (2.25 Å)