Electron cryo-microscopy reveals the structure of the archaeal thread filament

DOI: 10.1038/s41467-022-34652-4

Authors: Matthew C. Gaines (University of Exeter) , Michail N. Isupov (University of Exeter) , Shamphavi Sivabalasarma (University of Freiburg) , Risat U. I. Haque (University of Exeter) , Mathew Mclaren (University of Exeter) , Clara L. Mollat (University of Freiburg) , Patrick Tripp (University of Freiburg) , Alexander Neuhaus (University of Exeter) , Vicki A. M. Gold (University of Exeter) , Sonja-Verena Albers (University of Freiburg) , Bertram Daum (University of Exeter)
Co-authored by industrial partner: No

Type: Journal Paper
Journal: Nature Communications , VOL 13

State: Published (Approved)
Published: December 2022

Abstract: Pili are filamentous surface extensions that play roles in bacterial and archaeal cellular processes such as adhesion, biofilm formation, motility, cell-cell communication, DNA uptake and horizontal gene transfer. The model archaeaon Sulfolobus acidocaldarius assembles three filaments of the type-IV pilus superfamily (archaella, archaeal adhesion pili and UV-inducible pili), as well as a so-far uncharacterised fourth filament, named “thread”. Here, we report on the cryo-EM structure of the archaeal thread. The filament is highly glycosylated and consists of subunits of the protein Saci_0406, arranged in a head-to-tail manner. Saci_0406 displays structural similarity, but low sequence homology, to bacterial type-I pilins. Thread subunits are interconnected via donor strand complementation, a feature reminiscent of bacterial chaperone-usher pili. However, despite these similarities in overall architecture, archaeal threads appear to have evolved independently and are likely assembled by a distinct mechanism.

Diamond Keywords: Archaea

Subject Areas: Biology and Bio-materials

Diamond Offline Facilities: Electron Bio-Imaging Centre (eBIC)
Instruments: Krios I-Titan Krios I at Diamond

Added On: 08/12/2022 09:59

Documents:
s41467-022-34652-4.pdf

Discipline Tags:

Structural biology Life Sciences & Biotech

Technical Tags:

Microscopy Electron Microscopy (EM) Cryo Electron Microscopy (Cryo EM)