Next Article in Journal
Tuning the Emission Energy of Chemically Doped Graphene Quantum Dots
Next Article in Special Issue
The Electrosome: A Surface-Displayed Enzymatic Cascade in a Biofuel Cell’s Anode and a High-Density Surface-Displayed Biocathodic Enzyme
Previous Article in Journal
DNA Origami Reorganizes upon Interaction with Graphite: Implications for High-Resolution DNA Directed Protein Patterning
Previous Article in Special Issue
Effect of Graphene-Graphene Oxide Modified Anode on the Performance of Microbial Fuel Cell
Article Menu

Export Article

Open AccessArticle
Nanomaterials 2016, 6(11), 197; doi:10.3390/nano6110197

Nanoscale Electric Characteristics and Oriented Assembly of Halobacterium salinarum Membrane Revealed by Electric Force Microscopy

1
Agricultural Information Institute, Chinese Academy of Agricultural Sciences/Key Laboratory of Agricultural Information Service Technology of Ministry of Agriculture, Beijing 100081, China
2
CAS Key Laboratory of Standardization and Measurement for Nanotechnology, CAS Center for Excellence in Nanoscience, National Center for Nanoscience and Technology, Beijing 100190, China
*
Authors to whom correspondence should be addressed.
Academic Editor: Lital Alfonta
Received: 15 July 2016 / Revised: 28 September 2016 / Accepted: 8 October 2016 / Published: 2 November 2016
(This article belongs to the Special Issue Nanostructured Biofuel Cells)
View Full-Text   |   Download PDF [2612 KB, uploaded 2 November 2016]   |  

Abstract

Purple membranes (PM) of the bacteria Halobacterium salinarum are a unique natural membrane where bacteriorhodopsin (BR) can convert photon energy and pump protons. Elucidating the electronic properties of biomembranes is critical for revealing biological mechanisms and developing new devices. We report here the electric properties of PMs studied by using multi-functional electric force microscopy (EFM) at the nanoscale. The topography, surface potential, and dielectric capacity of PMs were imaged and quantitatively measured in parallel. Two orientations of PMs were identified by EFM because of its high resolution in differentiating electrical characteristics. The extracellular (EC) sides were more negative than the cytoplasmic (CP) side by 8 mV. The direction of potential difference may facilitate movement of protons across the membrane and thus play important roles in proton pumping. Unlike the side-dependent surface potentials observed in PM, the EFM capacitive response was independent of the side and was measured to be at a dC/dz value of ~5.25 nF/m. Furthermore, by modification of PM with de novo peptides based on peptide-protein interaction, directional oriented PM assembly on silicon substrate was obtained for technical devices. This work develops a new method for studying membrane nanoelectronics and exploring the bioelectric application at the nanoscale. View Full-Text
Keywords: electrostatic force microscopy (EFM); purple membrane (PM); surface potential; peptides; oriented assembly electrostatic force microscopy (EFM); purple membrane (PM); surface potential; peptides; oriented assembly
Figures

Figure 1

This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. (CC BY 4.0).

Supplementary material

Scifeed alert for new publications

Never miss any articles matching your research from any publisher
  • Get alerts for new papers matching your research
  • Find out the new papers from selected authors
  • Updated daily for 49'000+ journals and 6000+ publishers
  • Define your Scifeed now

SciFeed Share & Cite This Article

MDPI and ACS Style

Li, D.; Wang, Y.; Du, H.; Xu, S.; Li, Z.; Yang, Y.; Wang, C. Nanoscale Electric Characteristics and Oriented Assembly of Halobacterium salinarum Membrane Revealed by Electric Force Microscopy. Nanomaterials 2016, 6, 197.

Show more citation formats Show less citations formats

Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.

Related Articles

Article Metrics

Article Access Statistics

1

Comments

[Return to top]
Nanomaterials EISSN 2079-4991 Published by MDPI AG, Basel, Switzerland RSS E-Mail Table of Contents Alert
Back to Top