Abundance of the multiheme c-type cytochrome OmcB increases in outer biofilm layers of electrode-grown Geobacter sulfurreducens
| Autor: | Edward V. LaBelle, Daniel R. Bond, Camille S. Stephen, Susan L. Brantley |
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| Rok vydání: | 2014 |
| Předmět: |
Cytochrome
Standard hydrogen electrode Bioelectric Energy Sources Applied Microbiology lcsh:Medicine Bioenergetics Research and Analysis Methods Biochemistry Microbiology Microbial Ecology Electron Transport Electrochemistry lcsh:Science Geobacter sulfurreducens Electrodes Immunohistochemistry Techniques Multidisciplinary biology Ecology Chemistry Electron Transport Chain Electrode Potentials lcsh:R Biofilm Biology and Life Sciences Bacteriology Immunogold labelling biology.organism_classification Respiratory protein Histochemistry and Cytochemistry Techniques Standard electrode potential Biofilms Physical Sciences biology.protein Biophysics Engineering and Technology lcsh:Q Electronics Bacterial outer membrane Geobacter Bacterial Biofilms Oxidation-Reduction Bioremediation Bacterial Outer Membrane Proteins Research Article Biotechnology |
| Zdroj: | PLoS ONE PLoS ONE, Vol 9, Iss 8, p e104336 (2014) |
| ISSN: | 1932-6203 |
| Popis: | When Geobacter sulfurreducens utilizes an electrode as its electron acceptor, cells embed themselves in a conductive biofilm tens of microns thick. While environmental conditions such as pH or redox potential have been shown to change close to the electrode, less is known about the response of G. sulfurreducens to growth in this biofilm environment. To investigate whether respiratory protein abundance varies with distance from the electrode, antibodies against an outer membrane multiheme cytochrome (OmcB) and cytoplasmic acetate kinase (AckA) were used to determine protein localization in slices spanning ∼25 µm-thick G. sulfurreducens biofilms growing on polished electrodes poised at +0.24 V (vs. Standard Hydrogen Electrode). Slices were immunogold labeled post-fixing, imaged via transmission electron microscopy, and digitally reassembled to create continuous images allowing subcellular location and abundance per cell to be quantified across an entire biofilm. OmcB was predominantly localized on cell membranes, and 3.6-fold more OmcB was detected on cells 10-20 µm distant from the electrode surface compared to inner layers (0-10 µm). In contrast, acetate kinase remained constant throughout the biofilm, and was always associated with the cell interior. This method for detecting proteins in intact conductive biofilms supports a model where the utilization of redox proteins changes with depth. |
| Databáze: | OpenAIRE |
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