7S9Y

Helicobacter Hepaticus CcsBA Open Conformation

7S9Y の概要

• エントリーDOI: 10.2210/pdb7s9y/pdb
• EMDBエントリー: 24941
• 分子名称: Cytochrome c biogenesis protein, HEME B/C, PHOSPHATIDYLETHANOLAMINE (3 entities in total)
• 機能のキーワード: cytochrome c biogenesis, heme transporter, heme lyase, membrane protein
• 由来する生物種: Helicobacter hepaticus
• タンパク質・核酸の鎖数: 1
• 化学式量合計: 109262.51

構造登録者

Mendez, D.L.,Lowder, E.P.,Tillman, D.E.,Sutherland, M.C.,Collier, A.L.,Rau, M.J.,Fitzpatrick, J.A.,Kranz, R.G. (登録日: 2021-09-21, 公開日: 2021-12-22, 最終更新日: 2024-06-05)

主引用文献

Mendez, D.L.,Lowder, E.P.,Tillman, D.E.,Sutherland, M.C.,Collier, A.L.,Rau, M.J.,Fitzpatrick, J.A.J.,Kranz, R.G.
Cryo-EM of CcsBA reveals the basis for cytochrome c biogenesis and heme transport.
Nat.Chem.Biol., 18:101-108, 2022

PubMed Abstract: Although the individual structures and respiratory functions of cytochromes are well studied, the structural basis for their assembly, including transport of heme for attachment, are unknown. We describe cryo-electron microscopy (cryo-EM) structures of CcsBA, a bifunctional heme transporter and cytochrome c (cyt c) synthase. Models built from the cryo-EM densities show that CcsBA is trapped with heme in two conformations, herein termed the closed and open states. The closed state has heme located solely at a transmembrane (TM) site, with a large periplasmic domain oriented such that access of heme to the cytochrome acceptor is denied. The open conformation contains two heme moieties, one in the TM-heme site and another in an external site (P-heme site). The presence of heme in the periplasmic site at the base of a chamber induces a large conformational shift that exposes the heme for reaction with apocytochrome c (apocyt c). Consistent with these structures, in vivo and in vitro cyt c synthase studies suggest a mechanism for transfer of the periplasmic heme to cytochrome.

PubMed: 34931065
DOI: 10.1038/s41589-021-00935-y

実験手法

ELECTRON MICROSCOPY (3.56 Å)