4FGE

Structure of the effector protein Tse1 from Pseudomonas aeruginosa

4FGE の概要

• エントリーDOI: 10.2210/pdb4fge/pdb
• 関連するPDBエントリー: 4FGD 4FGI
• 分子名称: Tse1, CHLORIDE ION, THIOCYANATE ION, ... (5 entities in total)
• 機能のキーワード: n1pc/p60 superfamily, peptidoglycan hydrolase, cytosol, hydrolase
• 由来する生物種: Pseudomonas aeruginosa
• タンパク質・核酸の鎖数: 4
• 化学式量合計: 71378.97

構造登録者

Benz, J.,Sendlmeier, C.,Barends, T.R.M.,Meinhart, A. (登録日: 2012-06-04, 公開日: 2012-06-20, 最終更新日: 2024-02-28)

主引用文献

Benz, J.,Sendlmeier, C.,Barends, T.R.,Meinhart, A.
Structural Insights into the Effector - Immunity System Tse1/Tsi1 from Pseudomonas aeruginosa.
Plos One, 7:e40453-e40453, 2012

PubMed Abstract: During an interbacterial battle, the type-6-secretion-system (T6SS) of the human pathogen Pseudomonas aeruginosa injects the peptidoglycan(PG)-hydrolase Tse1 into the periplasm of gram-negative enemy cells and induces their lysis. However, for its own benefit, P. aeruginosa produces and transports the immunity-protein Tsi1 into its own periplasm where in prevents accidental exo- and endogenous intoxication. Here we present the high-resolution X-ray crystal structure of the lytic enzyme Tse1 and describe the mechanism by which Tse1 cleaves the γ-D-glutamyl-l-meso-diaminopimelic acid amide bond of crosslinked PG. Tse1 belongs to the superfamily of N1pC/P60 peptidases but is unique among described members of this family of which the structure was described, since it is a single domain protein without any putative localization domain. Most importantly, we present the crystal structure of Tse1 bound to its immunity-protein Tsi1 as well and describe the mechanism of enzyme inhibition. Tsi1 occludes the active site of Tse1 and abolishes its enzyme activity by forming a hydrogen bond to a catalytically important histidine residue in Tse1. Based on our structural findings in combination with a bioinfomatic approach we also identified a related system in Burkholderia phytofirmans. Not only do our findings point to a common catalytic mechanism of the Tse1 PG-hydrolases, but we can also show that it is distinct from other members of this superfamily. Furthermore, we provide strong evidence that the mechanism of enzyme inhibition between Tsi1 orthologues is conserved. This work is the first structural description of an entire effector/immunity pair injected by the T6SS system. Moreover, it is also the first example of a member of the N1pC/P60 superfamily which becomes inhibited upon binding to its cognate immunity protein.

PubMed: 22792331
DOI: 10.1371/journal.pone.0040453

実験手法

X-RAY DIFFRACTION (1.7 Å)