Reconstitution of respiratory complex I on a biomimetic membrane supported on gold electrodes

Langmuir. 2014 Jul 29;30(29):9007-15. doi: 10.1021/la501825r. Epub 2014 Jul 16.

Abstract

For the first time, respiratory complex I has been reconstituted on an electrode preserving its structure and activity. Respiratory complex I is a membrane-bound enzyme that has an essential function in cellular energy production. It couples NADH:quinone oxidoreduction to translocation of ions across the cellular (in prokaryotes) or mitochondrial membranes. Therefore, complex I contributes to the establishment and maintenance of the transmembrane difference of electrochemical potential required for adenosine triphosphate synthesis, transport, and motility. Our new strategy has been applied for reconstituting the bacterial complex I from Rhodothermus marinus onto a biomimetic membrane supported on gold electrodes modified with a thiol self-assembled monolayer (SAM). Atomic force microscopy and faradaic impedance measurements give evidence of the biomimetic construction, whereas electrochemical measurements show its functionality. Both electron transfer and proton translocation by respiratory complex I were monitored, simulating in vivo conditions.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Bacterial Proteins / chemistry*
  • Bacterial Proteins / isolation & purification
  • Biomimetic Materials
  • Electrodes
  • Electron Transport
  • Electron Transport Complex I / chemistry*
  • Electron Transport Complex I / isolation & purification
  • Gold / chemistry*
  • Membranes, Artificial
  • Microscopy, Atomic Force
  • Protons*
  • Rhodothermus / chemistry*
  • Rhodothermus / enzymology
  • Sulfhydryl Reagents / chemistry

Substances

  • Bacterial Proteins
  • Membranes, Artificial
  • Protons
  • Sulfhydryl Reagents
  • Gold
  • Electron Transport Complex I