7LQ5

Cryo-EM structure of OmcZ nanowire from Geobacter sulfurreducens

Summary for 7LQ5

• Entry DOI: 10.2210/pdb7lq5/pdb
• EMDB information: 23481
• Descriptor: Cytochrome c, HEME C (2 entities in total)
• Functional Keywords: nanowires, protein fibril
• Biological source: Geobacter sulfurreducens PCA
• Total number of polymer chains: 3
• Total formula weight: 97904.46

Authors

Gu, Y.,Srikanth, V.,Malvankar, N.S.,Samatey, F.A. (deposition date: 2021-02-13, release date: 2022-08-24, Last modification date: 2024-12-25)

Primary citation

Gu, Y.,Guberman-Pfeffer, M.J.,Srikanth, V.,Shen, C.,Giska, F.,Gupta, K.,Londer, Y.,Samatey, F.A.,Batista, V.S.,Malvankar, N.S.
Structure of Geobacter cytochrome OmcZ identifies mechanism of nanowire assembly and conductivity.
Nat Microbiol, 8:284-298, 2023

PubMed Abstract: OmcZ nanowires produced by Geobacter species have high electron conductivity (>30 S cm). Of 111 cytochromes present in G. sulfurreducens, OmcZ is the only known nanowire-forming cytochrome essential for the formation of high-current-density biofilms that require long-distance (>10 µm) extracellular electron transport. However, the mechanisms underlying OmcZ nanowire assembly and high conductivity are unknown. Here we report a 3.5-Å-resolution cryogenic electron microscopy structure for OmcZ nanowires. Our structure reveals linear and closely stacked haems that may account for conductivity. Surface-exposed haems and charge interactions explain how OmcZ nanowires bind to diverse extracellular electron acceptors and how organization of nanowire network re-arranges in different biochemical environments. In vitro studies explain how G. sulfurreducens employ a serine protease to control the assembly of OmcZ monomers into nanowires. We find that both OmcZ and serine protease are widespread in environmentally important bacteria and archaea, thus establishing a prevalence of nanowire biogenesis across diverse species and environments.

PubMed: 36732469
DOI: 10.1038/s41564-022-01315-5

Experimental method

ELECTRON MICROSCOPY (3.4 Å)