8E5F

Cryo-EM of P. calidifontis cytochrome filament

Summary for 8E5F

• Entry DOI: 10.2210/pdb8e5f/pdb
• EMDB information: 27911
• Descriptor: c-type cytochrome, HEME C (2 entities in total)
• Functional Keywords: helical symmetry, cytochrome filmanet, conductive nanowires, microbial nanowires, electron transport
• Biological source: Pyrobaculum calidifontis
• Total number of polymer chains: 1
• Total formula weight: 43230.32

Authors

Wang, F.,Cvirkaite-Krupovic, V.,Krupovic, M.,Egelman, E.H. (deposition date: 2022-08-22, release date: 2023-05-10, Last modification date: 2023-07-26)

Primary citation

Baquero, D.P.,Cvirkaite-Krupovic, V.,Hu, S.S.,Fields, J.L.,Liu, X.,Rensing, C.,Egelman, E.H.,Krupovic, M.,Wang, F.
Extracellular cytochrome nanowires appear to be ubiquitous in prokaryotes.
Cell, 186:2853-2864.e8, 2023

PubMed Abstract: Electrically conductive appendages from the anaerobic bacterium Geobacter sulfurreducens, recently identified as extracellular cytochrome nanowires (ECNs), have received wide attention due to numerous potential applications. However, whether other organisms employ similar ECNs for electron transfer remains unknown. Here, using cryoelectron microscopy, we describe the atomic structures of two ECNs from two major orders of hyperthermophilic archaea present in deep-sea hydrothermal vents and terrestrial hot springs. Homologs of Archaeoglobus veneficus ECN are widespread among mesophilic methane-oxidizing Methanoperedenaceae, alkane-degrading Syntrophoarchaeales archaea, and in the recently described megaplasmids called Borgs. The ECN protein subunits lack similarities in their folds; however, they share a common heme arrangement, suggesting an evolutionarily optimized heme packing for efficient electron transfer. The detection of ECNs in archaea suggests that filaments containing closely stacked hemes may be a common and widespread mechanism for long-range electron transfer in both prokaryotic domains of life.

PubMed: 37290436
DOI: 10.1016/j.cell.2023.05.012

Experimental method

ELECTRON MICROSCOPY (3.8 Å)