Engineering Geobacter pili to produce metal:organic filaments

Biosens Bioelectron. 2023 Feb 15:222:114993. doi: 10.1016/j.bios.2022.114993. Epub 2022 Dec 6.


The organized self-assembly of conductive biological structures holds promise for creating new bioelectronic devices. In particular, Geobacter sulfurreducens type IVa pili have proven to be a versatile material for fabricating protein nanowire-based devices. To scale the production of conductive pili, we designed a strain of Shewanella oneidensis that heterologously expressed abundant, conductive Geobacter pili when grown aerobically in liquid culture. S. oneidensis expressing a cysteine-modified pilin, designed to enhance the capability to bind to gold, generated conductive pili that self-assembled into biohybrid filaments in the presence of gold nanoparticles. Elemental composition analysis confirmed the filament-metal interactions within the structures, which were several orders of magnitude larger than previously described metal:organic filaments. The results demonstrate that the S. oneidensis chassis significantly advances the possibilities for facile conductive protein nanowire design and fabrication.

Keywords: Bioelectronics; Bioengineering; Biohybrid; Metal:organic; Pili; Self-assembly.

MeSH terms

  • Biosensing Techniques*
  • Electron Transport
  • Fimbriae, Bacterial / metabolism
  • Geobacter*
  • Gold
  • Metal Nanoparticles*


  • Gold