6NAV

Cryo-EM reconstruction of Sulfolobus islandicus LAL14/1 Pilus

Summary for 6NAV

• Entry DOI: 10.2210/pdb6nav/pdb
• EMDB information: 0397
• Descriptor: M9UD72 (1 entity in total)
• Functional Keywords: helical symmetry, archaeal pilus, structural protein
• Biological source: Sulfolobus islandicus LAL14/1
• Total number of polymer chains: 21
• Total formula weight: 266308.88

Authors

Wang, F.,Cvirkaite-Krupovic, V.,Prangishvili, D.,Krupovic, M.,Egelman, E.H. (deposition date: 2018-12-06, release date: 2019-05-08, Last modification date: 2024-03-20)

Primary citation

Wang, F.,Cvirkaite-Krupovic, V.,Kreutzberger, M.A.B.,Su, Z.,de Oliveira, G.A.P.,Osinski, T.,Sherman, N.,DiMaio, F.,Wall, J.S.,Prangishvili, D.,Krupovic, M.,Egelman, E.H.
An extensively glycosylated archaeal pilus survives extreme conditions.
Nat Microbiol, 4:1401-1410, 2019

PubMed Abstract: Pili on the surface of Sulfolobus islandicus are used for many functions, and serve as receptors for certain archaeal viruses. The cells grow optimally at pH 3 and ~80 °C, exposing these extracellular appendages to a very harsh environment. The pili, when removed from cells, resist digestion by trypsin or pepsin, and survive boiling in sodium dodecyl sulfate or 5 M guanidine hydrochloride. We used electron cryo-microscopy to determine the structure of these filaments at 4.1 Å resolution. An atomic model was built by combining the electron density map with bioinformatics without previous knowledge of the pilin sequence-an approach that should prove useful for assemblies where all of the components are not known. The atomic structure of the pilus was unusual, with almost one-third of the residues being either threonine or serine, and with many hydrophobic surface residues. While the map showed extra density consistent with glycosylation for only three residues, mass measurements suggested extensive glycosylation. We propose that this extensive glycosylation renders these filaments soluble and provides the remarkable structural stability. We also show that the overall fold of the archaeal pilin is remarkably similar to that of archaeal flagellin, establishing common evolutionary origins.

PubMed: 31110358
DOI: 10.1038/s41564-019-0458-x

Experimental method

ELECTRON MICROSCOPY (4.1 Å)