Download MendeleyStructure of Geobacter cytochrome OmcZ identifies mechanism of nanowire assembly and conductivity.
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.(2023) Nat Microbiol 8: 284-298
- PubMed: 36732469
- DOI: https://doi.org/10.1038/s41564-022-01315-5
- Primary Citation of Related Structures:
7LQ5 - PubMed Abstract:
OmcZ nanowires produced by Geobacter species have high electron conductivity (>30 S cm -1 ). 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.
Organizational Affiliation:
Microbial Sciences Institute, Yale University, West Haven, CT, USA. ygu@mrc-lmb.cam.ac.uk.
