5A42

Cryo-EM single particle 3D reconstruction of the native conformation of E. coli alpha-2-macroglobulin (ECAM)

5A42 の概要

• エントリーDOI: 10.2210/pdb5a42/pdb
• EMDBエントリー: 3016
• 分子名称: UNCHARACTERIZED LIPOPROTEIN YFHM (1 entity in total)
• 機能のキーワード: hydrolase inhibitor, peptidase inhibitor
• 由来する生物種: ESCHERICHIA COLI K-12
• 細胞内の位置: Cell membrane ; Lipid-anchor : P76578
• タンパク質・核酸の鎖数: 1
• 化学式量合計: 177690.30

構造登録者

Garcia-Ferrer, I.,Arede, P.,Gomez-Blanco, J.,Luque, D.,Duquerroy, S.,Caston, J.R.,Goulas, T.,Gomis-Ruth, F.X. (登録日: 2015-06-04, 公開日: 2015-07-29, 最終更新日: 2024-05-08)

主引用文献

Garcia-Ferrer, I.,Arede, P.,Gomez-Blanco, J.,Luque, D.,Duquerroy, S.,Caston, J.R.,Goulas, T.,Gomis-Ruth, F.X.
Structural and Functional Insights Into Escherichia Coli Alpha2- Macroglobulin Endopeptidase Snap-Trap Inhibition.
Proc.Natl.Acad.Sci.USA, 112:8290-, 2015

PubMed Abstract: The survival of commensal bacteria requires them to evade host peptidases. Gram-negative bacteria from the human gut microbiome encode a relative of the human endopeptidase inhibitor, α2-macroglobulin (α2M). Escherichia coli α2M (ECAM) is a ∼ 180-kDa multidomain membrane-anchored pan-peptidase inhibitor, which is cleaved by host endopeptidases in an accessible bait region. Structural studies by electron microscopy and crystallography reveal that this cleavage causes major structural rearrangement of more than half the 13-domain structure from a native to a compact induced form. It also exposes a reactive thioester bond, which covalently traps the peptidase. Subsequently, peptidase-laden ECAM is shed from the membrane and may dimerize. Trapped peptidases are still active except against very large substrates, so inhibition potentially prevents damage of large cell envelope components, but not host digestion. Mechanistically, these results document a novel monomeric "snap trap."

PubMed: 26100869
DOI: 10.1073/PNAS.1506538112

実験手法

ELECTRON MICROSCOPY (16 Å)