4V3A

Membrane bound pleurotolysin prepore (TMH1 lock) trapped with engineered disulphide cross-link

4V3A の概要

• エントリーDOI: 10.2210/pdb4v3a/pdb
• 関連するPDBエントリー: 4V2T 4V3M 4V3N
• EMDBエントリー: 2794
• 分子名称: PLEUROTOLYSIN A, PLEUROTOLYSIN B (2 entities in total)
• 機能のキーワード: transport protein, macpf/cdc superfamily, pore-forming proteins
• 由来する生物種: PLEUROTUS OSTREATUS (OYSTER MUSHROOM); 詳細
• タンパク質・核酸の鎖数: 3
• 化学式量合計: 72615.75

構造登録者

Lukoyanova, N.,Kondos, S.C.,Farabella, I.,Law, R.H.P.,Reboul, C.F.,CaradocDavies, T.T.,Spicer, B.A.,Kleifeld, O.,Perugini, M.,Ekkel, S.,Hatfaludi, T.,Oliver, K.,Hotze, E.M.,Tweten, R.K.,Whisstock, J.C.,Topf, M.,Dunstone, M.A.,Saibil, H.R. (登録日: 2014-10-17, 公開日: 2015-02-18, 最終更新日: 2024-05-08)

主引用文献

Lukoyanova, N.,Kondos, S.C.,Farabella, I.,Law, R.H.P.,Reboul, C.F.,Caradoc-Davies, T.T.,Spicer, B.A.,Kleifeld, O.,Traore, D.A.K.,Ekkel, S.M.,Voskoboinik, I.,Trapani, J.A.,Hatfaludi, T.,Oliver, K.,Hotze, E.M.,Tweten, R.K.,Whisstock, J.C.,Topf, M.,Saibil, H.R.,Dunstone, M.A.
Conformational Changes During Pore Formation by the Perforin-Related Protein Pleurotolysin.
Plos Biol., 13:02049-, 2015

PubMed Abstract: Membrane attack complex/perforin-like (MACPF) proteins comprise the largest superfamily of pore-forming proteins, playing crucial roles in immunity and pathogenesis. Soluble monomers assemble into large transmembrane pores via conformational transitions that remain to be structurally and mechanistically characterised. Here we present an 11 Å resolution cryo-electron microscopy (cryo-EM) structure of the two-part, fungal toxin Pleurotolysin (Ply), together with crystal structures of both components (the lipid binding PlyA protein and the pore-forming MACPF component PlyB). These data reveal a 13-fold pore 80 Å in diameter and 100 Å in height, with each subunit comprised of a PlyB molecule atop a membrane bound dimer of PlyA. The resolution of the EM map, together with biophysical and computational experiments, allowed confident assignment of subdomains in a MACPF pore assembly. The major conformational changes in PlyB are a ∼70° opening of the bent and distorted central β-sheet of the MACPF domain, accompanied by extrusion and refolding of two α-helical regions into transmembrane β-hairpins (TMH1 and TMH2). We determined the structures of three different disulphide bond-trapped prepore intermediates. Analysis of these data by molecular modelling and flexible fitting allows us to generate a potential trajectory of β-sheet unbending. The results suggest that MACPF conformational change is triggered through disruption of the interface between a conserved helix-turn-helix motif and the top of TMH2. Following their release we propose that the transmembrane regions assemble into β-hairpins via top down zippering of backbone hydrogen bonds to form the membrane-inserted β-barrel. The intermediate structures of the MACPF domain during refolding into the β-barrel pore establish a structural paradigm for the transition from soluble monomer to pore, which may be conserved across the whole superfamily. The TMH2 region is critical for the release of both TMH clusters, suggesting why this region is targeted by endogenous inhibitors of MACPF function.

PubMed: 25654333
DOI: 10.1371/JOURNAL.PBIO.1002049

実験手法

ELECTRON MICROSCOPY (15 Å)