8SXF

The C-terminal protease CtpA-LbcA complex of pseudomonas aeruginosa with the TPR at the high position

8SXF の概要

• エントリーDOI: 10.2210/pdb8sxf/pdb
• EMDBエントリー: 40847 40850
• 分子名称: Probable carboxyl-terminal protease, TPR repeat-containing protein PA4667, polyA (3 entities in total)
• 機能のキーワード: ctpa, lbca, c-terminal protease, pseudomonas aeruginosa, hydrolase
• 由来する生物種: Pseudomonas aeruginosa; 詳細
• タンパク質・核酸の鎖数: 5
• 化学式量合計: 191032.02

構造登録者

Hsu, H.-C.,Li, H. (登録日: 2023-05-22, 公開日: 2024-03-06, 最終更新日: 2024-04-24)

主引用文献

Hsu, H.C.,Wang, M.,Kovach, A.,Darwin, A.J.,Li, H.
P. aeruginosa CtpA protease adopts a novel activation mechanism to initiate the proteolytic process.
Embo J., 43:1634-1652, 2024

PubMed Abstract: During bacterial cell growth, hydrolases cleave peptide cross-links between strands of the peptidoglycan sacculus to allow new strand insertion. The Pseudomonas aeruginosa carboxyl-terminal processing protease (CTP) CtpA regulates some of these hydrolases by degrading them. CtpA assembles as an inactive hexamer composed of a trimer-of-dimers, but its lipoprotein binding partner LbcA activates CtpA by an unknown mechanism. Here, we report the cryo-EM structures of the CtpA-LbcA complex. LbcA has an N-terminal adaptor domain that binds to CtpA, and a C-terminal superhelical tetratricopeptide repeat domain. One LbcA molecule attaches to each of the three vertices of a CtpA hexamer. LbcA triggers relocation of the CtpA PDZ domain, remodeling of the substrate binding pocket, and realignment of the catalytic residues. Surprisingly, only one CtpA molecule in a CtpA dimer is activated upon LbcA binding. Also, a long loop from one CtpA dimer inserts into a neighboring dimer to facilitate the proteolytic activity. This work has revealed an activation mechanism for a bacterial CTP that is strikingly different from other CTPs that have been characterized structurally.

PubMed: 38467832
DOI: 10.1038/s44318-024-00069-6

実験手法

ELECTRON MICROSCOPY (3.92 Å)