4U59

Crystal structure of Salmonella alpha-2-macroglobulin reacted with methylamine

4U59 の概要

• エントリーDOI: 10.2210/pdb4u59/pdb
• 分子名称: alpha-2-macroglobulin (1 entity in total)
• 機能のキーワード: macroglobulin, thioester, protease inhibitor, methylamine, hydrolase inhibitor
• 由来する生物種: Salmonella typhimurium
• タンパク質・核酸の鎖数: 1
• 化学式量合計: 180068.23

構造登録者

Wong, S.G.,Dessen, A. (登録日: 2014-07-24, 公開日: 2014-09-17, 最終更新日: 2024-11-06)

主引用文献

Wong, S.G.,Dessen, A.
Structure of a bacterial alpha 2-macroglobulin reveals mimicry of eukaryotic innate immunity.
Nat Commun, 5:4917-4917, 2014

PubMed Abstract: Alpha-2-macroglobulins (A2Ms) are plasma proteins that trap and inhibit a broad range of proteases and are major components of the eukaryotic innate immune system. Surprisingly, A2M-like proteins were identified in pathogenically invasive bacteria and species that colonize higher eukaryotes. Bacterial A2Ms are located in the periplasm where they are believed to provide protection to the cell by trapping external proteases through a covalent interaction with an activated thioester. Here we report the crystal structures and characterization of Salmonella enterica ser. Typhimurium A2M in different states of thioester activation. The structures reveal thirteen domains whose arrangement displays high similarity to proteins involved in eukaryotic immune defence. A structural lock mechanism maintains the stability of the buried thioester, a requirement for its protease-trapping activity. These findings indicate that bacteria have developed a rudimentary innate immune system whose mechanism mimics that of eukaryotes.

PubMed: 25221932
DOI: 10.1038/ncomms5917

実験手法

X-RAY DIFFRACTION (3.09 Å)