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Architecture and modular assembly of Sulfolobus S-layers revealed by electron cryotomography.

ABSTRACT: Surface protein layers (S-layers) often form the only structural component of the archaeal cell wall and are therefore important for cell survival. S-layers have a plethora of cellular functions including maintenance of cell shape, osmotic, and mechanical stability, the formation of a semipermeable protective barrier around the cell, and cell-cell interaction, as well as surface adhesion. Despite the central importance of S-layers for archaeal life, their 3-dimensional (3D) architecture is still poorly understood. Here we present detailed 3D electron cryomicroscopy maps of archaeal S-layers from 3 different Sulfolobus strains. We were able to pinpoint the positions and determine the structure of the 2 subunits SlaA and SlaB. We also present a model describing the assembly of the mature S-layer.

SUBMITTER: Gambelli L

PROVIDER: S-EPMC6911244 | biostudies-literature | 2019 Dec

REPOSITORIES: biostudies-literature

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Architecture and modular assembly of <i>Sulfolobus</i> S-layers revealed by electron cryotomography.

Gambelli Lavinia L Meyer Benjamin H BH McLaren Mathew M Sanders Kelly K Quax Tessa E F TEF Gold Vicki A M VAM Albers Sonja-Verena SV Daum Bertram B

Proceedings of the National Academy of Sciences of the United States of America 20191125 50

Surface protein layers (S-layers) often form the only structural component of the archaeal cell wall and are therefore important for cell survival. S-layers have a plethora of cellular functions including maintenance of cell shape, osmotic, and mechanical stability, the formation of a semipermeable protective barrier around the cell, and cell-cell interaction, as well as surface adhesion. Despite the central importance of S-layers for archaeal life, their 3-dimensional (3D) architecture is still ...[more]

PMID: 31767763

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