3SLJ

Pre-cleavage Structure of the Autotransporter EspP - N1023A mutant

3SLJ の概要

• エントリーDOI: 10.2210/pdb3slj/pdb
• 関連するPDBエントリー: 3SLO 3SLT
• 分子名称: Serine protease espP, (HYDROXYETHYLOXY)TRI(ETHYLOXY)OCTANE (3 entities in total)
• 機能のキーワード: beta barrel, membrane protein, asparagine cyclization, autocleavage, protein transport
• 由来する生物種: Escherichia coli
• 細胞内の位置: Serine protease EspP: Periplasm . Secreted autotransporter protein EspP: Secreted. Autotransporter protein EspP translocator: Cell outer membrane ; Multi-pass membrane protein : Q7BSW5
• タンパク質・核酸の鎖数: 1
• 化学式量合計: 37175.94

構造登録者

Barnard, T.B.,Noinaj, N.,Easley, N.C.,Kuszak, A.J.,Buchanan, S.K. (登録日: 2011-06-24, 公開日: 2011-11-16, 最終更新日: 2023-09-13)

主引用文献

Barnard, T.J.,Gumbart, J.,Peterson, J.H.,Noinaj, N.,Easley, N.C.,Dautin, N.,Kuszak, A.J.,Tajkhorshid, E.,Bernstein, H.D.,Buchanan, S.K.
Molecular basis for the activation of a catalytic asparagine residue in a self-cleaving bacterial autotransporter.
J.Mol.Biol., 415:128-142, 2012

PubMed Abstract: Autotransporters are secreted proteins produced by pathogenic Gram-negative bacteria. They consist of a membrane-embedded β-domain and an extracellular passenger domain that is sometimes cleaved and released from the cell surface. We solved the structures of three noncleavable mutants of the autotransporter EspP to examine how it promotes asparagine cyclization to cleave its passenger. We found that cyclization is facilitated by multiple factors. The active-site asparagine is sterically constrained to conformations favorable for cyclization, while electrostatic interactions correctly orient the carboxamide group for nucleophilic attack. During molecular dynamics simulations, water molecules were observed to enter the active site and to form hydrogen bonds favorable for increasing the nucleophilicity of the active-site asparagine. When the activated asparagine attacks its main-chain carbonyl carbon, the resulting oxyanion is stabilized by a protonated glutamate. Upon cleavage, this proton could be transferred to the leaving amine group, helping overcome a significant energy barrier. Together, these findings provide insight into factors important for asparagine cyclization, a mechanism broadly used for protein cleavage.

PubMed: 22094314
DOI: 10.1016/j.jmb.2011.10.049

実験手法

X-RAY DIFFRACTION (2.481 Å)