Three-dimensional imaging of isolated membrane-protein complexes in vacuo with an X-ray laser
Abstract
The prospect of imaging single biomolecules, viruses and cells with intense, ultrashort X-ray pulses has driven the development of X-ray free-electron lasers (XFELs). However, the weak scattering from small particles is easily swamped by background from residual gas, which has so far limited applications to strongly scattering targets such as viruses, cell organelles and cells. Here we report a three-dimensional (3D) reconstruction of an isolated 1-MDa membrane-protein complex, photosystem I (PS I), from single-particle diffraction data. PS I trimers were aerosolised by charge-reduction electrospray ionisation and injected into the European XFEL beam, with partial helium gas exchange reducing background scattering by 80%. From 32 788 diffraction patterns of single trimers in random orientations, we reconstructed the 3D electron density to a resolution of 3.8 nm, limited by the detector geometry. The disc-shaped density, about 22 nm across and 10 nm thick, matches the size of a PS I trimer in a detergent micelle and is consistent with the compaction predicted by molecular dynamics simulations of the complex in vacuo and observed in native mass spectrometry. These results show that membrane-protein complexes can be imaged in vacuo with X-ray lasers, an important step towards ultrafast diffractive imaging of single macromolecules.
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BibTeX
@misc{ayyer2026threedimensional,
title = {{Three-dimensional imaging of isolated membrane-protein complexes in vacuo with an X-ray laser}},
author = {Kartik Ayyer and Tej Varma Yenupuri and Johan Bielecki and Lutz A. Eichacker and J. Domingo Meza-Aguilar and Louise J. Persson and Lena Worbs and Patrick Adams and Roberto Alvarez and Adil Ansari and Alfredo Bellisario and Rebecca Boll and Carl Caleman and Sebastian Cardoch and Andrea Castoldi and Joe P. J. Chen and Cyril Danilevski and Merle Dechering and Simon Dold and Armando D. Estillore and Alberto De Fanis and Lukas V. Haas and Patrick Konold and David Lomitze and Abhishek Mall and Dimitra Manatou and Iñaki de Diego Martinez and Parichita Mazumder and Andrew J. Morgan and Anna Munke and Yevheniy Ovcharenko and Matteo Porro and Safi Rafie-Zinedine and Amit K. Samanta and Christina Schmidt and Arezu Sehati and Jonas A. Sellberg and Björn Senfftleben and Carolin Seuring and Zhou Shen and Nicusor Timneanu and Sergey Usenko and Daniel Westphal and August Wollter and Tamme Wollweber and Paul Lourdu Xavier and Henry N. Chapman and Janos Hajdu and Richard A. Kirian and Jochen Küpper and Erik G. Marklund and Petra Fromme and Michael Meyer and Filipe R. N. C. Maia},
howpublished = {arXiv},
year = {2026},
month = oct,
doi = {10.48550/arxiv.2610.11729},
eprint = {2610.11729},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2610.11729},
note = {CC BY 4.0},
}
RIS
TY - UNPB
TI - Three-dimensional imaging of isolated membrane-protein complexes in vacuo with an X-ray laser
AU - Kartik Ayyer
AU - Tej Varma Yenupuri
AU - Johan Bielecki
AU - Lutz A. Eichacker
AU - J. Domingo Meza-Aguilar
AU - Louise J. Persson
AU - Lena Worbs
AU - Patrick Adams
AU - Roberto Alvarez
AU - Adil Ansari
AU - Alfredo Bellisario
AU - Rebecca Boll
AU - Carl Caleman
AU - Sebastian Cardoch
AU - Andrea Castoldi
AU - Joe P. J. Chen
AU - Cyril Danilevski
AU - Merle Dechering
AU - Simon Dold
AU - Armando D. Estillore
AU - Alberto De Fanis
AU - Lukas V. Haas
AU - Patrick Konold
AU - David Lomitze
AU - Abhishek Mall
AU - Dimitra Manatou
AU - Iñaki de Diego Martinez
AU - Parichita Mazumder
AU - Andrew J. Morgan
AU - Anna Munke
AU - Yevheniy Ovcharenko
AU - Matteo Porro
AU - Safi Rafie-Zinedine
AU - Amit K. Samanta
AU - Christina Schmidt
AU - Arezu Sehati
AU - Jonas A. Sellberg
AU - Björn Senfftleben
AU - Carolin Seuring
AU - Zhou Shen
AU - Nicusor Timneanu
AU - Sergey Usenko
AU - Daniel Westphal
AU - August Wollter
AU - Tamme Wollweber
AU - Paul Lourdu Xavier
AU - Henry N. Chapman
AU - Janos Hajdu
AU - Richard A. Kirian
AU - Jochen Küpper
AU - Erik G. Marklund
AU - Petra Fromme
AU - Michael Meyer
AU - Filipe R. N. C. Maia
PY - 2026
DA - 2026/10/08
PB - arXiv
DO - 10.48550/arxiv.2610.11729
UR - https://arxiv.org/abs/2610.11729
AB - The prospect of imaging single biomolecules, viruses and cells with intense, ultrashort X-ray pulses has driven the development of X-ray free-electron lasers (XFELs). However, the weak scattering from small particles is easily swamped by background from residual gas, which has so far limited applications to strongly scattering targets such as viruses, cell organelles and cells. Here we report a three-dimensional (3D) reconstruction of an isolated 1-MDa membrane-protein complex, photosystem I (PS I), from single-particle diffraction data. PS I trimers were aerosolised by charge-reduction electrospray ionisation and injected into the European XFEL beam, with partial helium gas exchange reducing background scattering by 80%. From 32 788 diffraction patterns of single trimers in random orientations, we reconstructed the 3D electron density to a resolution of 3.8 nm, limited by the detector geometry. The disc-shaped density, about 22 nm across and 10 nm thick, matches the size of a PS I trimer in a detergent micelle and is consistent with the compaction predicted by molecular dynamics simulations of the complex in vacuo and observed in native mass spectrometry. These results show that membrane-protein complexes can be imaged in vacuo with X-ray lasers, an important step towards ultrafast diffractive imaging of single macromolecules.
ER -