Evidence for High Conductivity in the Pili of \textit{Geobacter sulfurreducens}: ``Nano-wires'' in a Prokaryotic Electron Transport Chain?

ORAL

Abstract

We discuss results of Conducting-Probe Atomic Force Microscopy (CP-AFM) applied to the nanoscopic filamentary pili of the prokaryote \textit{Geobacter sulfurreducens.} (G. Reguera, et al., Nature \textbf{435}, 1038, 2005) The apparently high cross-axis conductivity of this bacterial membrane protein complex, along with evidence of its necessity for respiratory reduction of insoluble Fe(III) deposits in nature, points to the possibility of a novel role for the pili protein complex in the electron transport chain of a prokaryote: as a kind of ``nano-wire'' for conduction of electrons to Fe(III) oxides. CP-AFM and \textit{in vivo} genetic engineering experiments supporting the ``nano-wire'' hypothesis are presented.

*This work was supported by DOE cooperative agreement DE-FC02-02ER63446 and NSF grant DMR-0306951

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Authors

  • Kevin D. McCarthy

    • Dept. of Physics and Dept. of Microbiology, UMass

  • Gemma Reguera

  • Teena Mehta

  • Julie S. Nicoll

    • Dept. of Microbiology, UMass

  • Xinyu Wang

    • Dept. of Phyics, UMass

  • Mark T. Tuominen

  • Derek R. Lovley

    • Dept. of Microbiology and The Geobacter Project, UMass