Structure of the two-component S-layer of the archaeon Sulfolobus acidocaldarius
- MRC Laboratory of Molecular Biology, United Kingdom
- University of Exeter, United Kingdom
- Max Planck Institute of Biophysics, Germany
- Inserm U894, University Paris-Descartes, France
Abstract
Surface layers (S-layers) are resilient two-dimensional protein lattices that encapsulate many bacteria and most archaea. In archaea, S-layers usually form the only structural component of the cell wall and thus act as the final frontier between the cell and its environment. Therefore, S-layers are crucial for supporting microbial life. Notwithstanding their importance, little is known about archaeal S-layers at the atomic level. Here, we combined single particle cryo electron microscopy (cryoEM), cryo electron tomography (cryoET) and Alphafold2 predictions to generate an atomic model of the two-component S-layer of Sulfolobus acidocaldarius. The outer component of this S-layer (SlaA) is a flexible, highly glycosylated, and stable protein. Together with the inner and membrane-bound component (SlaB), they assemble into a porous and interwoven lattice. We hypothesise that jackknife-like conformational changes, changes play important roles in S-layer assembly.
Data availability
The atomic coordinates of SlaA were deposited in the Protein Data Bank (https://www.rcsb.org/) with accession numbers PDB-7ZCX, PDDB-8AN3, and PDB-8AN3 for pH 4, 7 and 10, respectively. The electron density maps were deposited in the EM DataResource (https://www.emdataresource.org/) with accession numbers EMD-14635, EMD-15531 and EMD-15531 for pH 4, 7 and 10, respectively.Sub-tomogram averaging map of the S-layer has been deposited in the EMDB (EMD-18127) and models of the hexameric and trimeric pores in the Protein Databank under accession codes PDB-8QP0 and PDB-8QOX, respectivelyOther structural data used in this study are: H. volcanii csg (PDB ID: 7PTR, http://dx.doi.org/10.2210/pdb7ptr/pdb), and C. crescentus RsaA ((N-terminus PDB ID: 6T72, http://dx.doi.org/10.2210/pdb6t72/pdb, C-terminus PDB ID: 5N8P, http://dx.doi.org/10.2210/pdb5n8p/pdb).
Article and author information
Author details
Funding
European Research Council (803894)
- Lavinia Gambelli
- Mathew McLaren
- Rebecca Conners
- Kelly Sanders
- Matthew C Gaines
- Bertram Daum
Wellcome Trust (210363/Z/18/Z)
- Rebecca Conners
- Vicki AM Gold
Wellcome Trust (212439/Z/18/Z)
- Bertram Daum
Agence Nationale de la Recherche (ANR-16-CE16-0009-01)
- Cyril Hanus
Agence Nationale de la Recherche (ANR-21-CE16-0021-01)
- Cyril Hanus
Leverhulme Trust (RPG-2020-261)
- Daniel Kattnig
Biotechnology and Biological Sciences Research Council (BB/R008639/1)
- Rebecca Conners
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2024, Gambelli et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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Structure of the two-component S-layer of the archaeon Sulfolobus acidocaldarius
eLife 13:e84617.
https://doi.org/10.7554/eLife.84617
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