PspA adopts an ESCRT-III-like fold and remodels bacterial membranes

Junglas, B., Huber, S. T., Heidler, T., Schlosser, L., Mann, D., Hennig, R., Clarke, M. , Hellmann, N., Schneider, D. and Sachse, C. (2021) PspA adopts an ESCRT-III-like fold and remodels bacterial membranes. Cell, 184(14), 3674-3688.e18. (doi: 10.1016/j.cell.2021.05.042) (PMID:34166616)

Abstract

PspA is the main effector of the phage shock protein (Psp) system and preserves the bacterial inner membrane integrity and function. Here, we present the 3.6 Å resolution cryoelectron microscopy (cryo-EM) structure of PspA assembled in helical rods. PspA monomers adopt a canonical ESCRT-III fold in an extended open conformation. PspA rods are capable of enclosing lipids and generating positive membrane curvature. Using cryo-EM, we visualized how PspA remodels membrane vesicles into μm-sized structures and how it mediates the formation of internalized vesicular structures. Hotspots of these activities are zones derived from PspA assemblies, serving as lipid transfer platforms and linking previously separated lipid structures. These membrane fusion and fission activities are in line with the described functional properties of bacterial PspA/IM30/LiaH proteins. Our structural and functional analyses reveal that bacterial PspA belongs to the evolutionary ancestry of ESCRT-III proteins involved in membrane remodeling.

• Item Type: Articles
• Additional Information: This work was funded by the Max-Planck Graduate Center at the Max Planck Institutes and the University of Mainz. This work has been initially supported by iNEXT (653706) funded by the Horizon 2020 program of the European Union.
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Clarke, Dr Mairi
• Authors: Junglas, B., Huber, S. T., Heidler, T., Schlosser, L., Mann, D., Hennig, R., Clarke, M., Hellmann, N., Schneider, D., and Sachse, C.
• College/School: College of Medical Veterinary and Life Sciences > School of Infection & Immunity; College of Medical Veterinary and Life Sciences > School of Infection & Immunity > Centre for Virus Research
• Journal Name: Cell
• Publisher: Elsevier (Cell Press)
• ISSN: 0092-8674
• ISSN (Online): 1097-4172
• Published Online: 23 June 2021
• Copyright Holders: Copyright © 2021 Elsevier
• First Published: First published in Cell 184(14): 3674-3688.e18
• Publisher Policy: Reproduced in accordance with the copyright policy of the publisher