5ODW

Structure of the FpvAI-pyocin S2 complex

5ODW の概要

• エントリーDOI: 10.2210/pdb5odw/pdb
• 分子名称: Ferripyoverdine receptor, Pyocin-S2, SULFATE ION (3 entities in total)
• 機能のキーワード: antimicrobial protein, membrane protein complex, protein transport
• 由来する生物種: Pseudomonas aeruginosa (strain ATCC 15692 / DSM 22644 / CIP 104116 / JCM 14847 / LMG 12228 / 1C / PRS 101 / PAO1); 詳細
• 細胞内の位置: Cell outer membrane: P48632
• タンパク質・核酸の鎖数: 4
• 化学式量合計: 232052.79

構造登録者

White, P.,Joshi, A.,Kleanthous, C. (登録日: 2017-07-06, 公開日: 2017-11-08, 最終更新日: 2024-01-17)

主引用文献

White, P.,Joshi, A.,Rassam, P.,Housden, N.G.,Kaminska, R.,Goult, J.D.,Redfield, C.,McCaughey, L.C.,Walker, D.,Mohammed, S.,Kleanthous, C.
Exploitation of an iron transporter for bacterial protein antibiotic import.
Proc. Natl. Acad. Sci. U.S.A., 114:12051-12056, 2017

PubMed Abstract: Unlike their descendants, mitochondria and plastids, bacteria do not have dedicated protein import systems. However, paradoxically, import of protein bacteriocins, the mechanisms of which are poorly understood, underpins competition among pathogenic and commensal bacteria alike. Here, using X-ray crystallography, isothermal titration calorimetry, confocal fluorescence microscopy, and in vivo photoactivatable cross-linking of stalled translocation intermediates, we demonstrate how the iron transporter FpvAI in the opportunistic pathogen is hijacked to translocate the bacteriocin pyocin S2 (pyoS2) across the outer membrane (OM). FpvAI is a TonB-dependent transporter (TBDT) that actively imports the small siderophore ferripyoverdine (Fe-Pvd) by coupling to the proton motive force (PMF) via the inner membrane (IM) protein TonB1. The crystal structure of the N-terminal domain of pyoS2 (pyoS2) bound to FpvAI ( = 240 pM) reveals that the pyocin mimics Fe-Pvd, inducing the same conformational changes in the receptor. Mimicry leads to fluorescently labeled pyoS2 being imported into FpvAI-expressing cells by a process analogous to that used by bona fide TBDT ligands. PyoS2 induces unfolding by TonB1 of a force-labile portion of the plug domain that normally occludes the central channel of FpvAI. The pyocin is then dragged through this narrow channel following delivery of its own TonB1-binding epitope to the periplasm. Hence, energized nutrient transporters in bacteria also serve as rudimentary protein import systems, which, in the case of FpvAI, results in a protein antibiotic 60-fold bigger than the transporter's natural substrate being translocated across the OM.

PubMed: 29078392
DOI: 10.1073/pnas.1713741114

実験手法

X-RAY DIFFRACTION (2.8 Å)