Bacterial nanowires

El-Naggar MY, Wanger G, Leung KM, Yuzvinsky TD, Southam G, Yang J, Lau WM, Nealson KH, Gorby YA. Electrical transport along bacterial nanowires from ShewaneUa oneidensis MR-1. Proc Natl Acad Sci USA 2010 107 18127-18131. 

Leung KM, Wanger G, El-Naggar MY, Gorby Y, Southam G, Lau WM, Yang J. She-wanella oneidensis MR-1 bacterial nanowires exhibit p-type, tunable electronic behavior. Nano Lett 2013 13 2407-2411. 

Polizzi NF, Skourtis SS, Beratan DN. Physical constraints on charge transport through bacterial nanowires. Earaday Discuss 2012 155 43-62. 

Gorby YA et al (2(X)6) Electrically conductive bacterial nanowires produced by Shewanella oneidensis strain MR-1 and other microorganisms. Proc Natl Acad Sci USA 103 11358-11363... 

Elias, D.A., Keimedy, D.W., Pinchuk, G., Watanabe, K., Ishii, S.I., Logan, B., and Nealson, K.H., and Fredrickson, J.K. (2006) Electrically conductive bacterial nanowires produced by Shewanella oneidemis strain MR-1 and other microorganisms. Proceedings of the National Academy of Sciences of the United States of America, 103,11358-11363. 

Thus, electrons can be directly transferred (DET) to the anode via the cell membrane (a) or via so-called nanowires (b) [vi.vii]. Alternatively, mediated electron transfer (MET) can take place via bacterial electron-shuttling compounds [viii] or reduced secondary metabolites like, e.g., hydrogen, formate, or ethanol [v,ix]. 

Biotemplates have been fabricated from two-dimensional crystalline surface proteins for the subsequent electrochemical deposition of nanowire structures [82]. These surface layer proteins encapsulate certain bacterial cells, controlling extracellular transport. They form especially robust thin films over cells, and are resistant to conditions that normally denature proteins, such as low pH and heat, thus making them ideal as template materials for electrodeposition. Schwartz and coworkers investigated a hexagonally packed intermediate surface layer protein from... 

Zhang and Qi synthesized hybrid bacterial cellulose/titania. They obtained mesoporous Titania networks consisting of nanowires, using as a template bacterial cellulose membrane. The network obtained shows Titania photocatalytic activity [46]. Composites of cellulose acetate/silica were obtained by sol-gel method [47]. Tanaka and Kozuka precipitated silica by acid catalysis of tetraethyl orthosilicate (TEOS). The composites of cellulose acetate/silica showed... 

Zhang, D., Qi, L. Synthesis of mesoporous titania networks consisting of anatase nanowires by templating of bacterial cellulose membranes. Chem. Common. 21, 2735-2737 (2005)... 

Nanowires in the microchip industry and as nanowaveguides for electromagnetic radiation, for solvent evaporation of hydrophobic nanoparticle molecular crosslinking in colloidal aggregates and templates [45-47], and in assemblies using biomacromolecules [48] such as DNA [49] and bacterial S-layer proteins [50]... 

D. Zhang, and L. Qi, Synthesis of mesoporous titania networks consisting of anatase nanowires by templating of bacterial cellulose membranes. Chem. Commun. 21,2735-2737 (2005). D. Mullera, C. R. Rambo, L. M. Portoc, W. H. Schreiner, and G. M. O. Barra, Structure and properties of polypyrrole/bacterial cellulose nanocomposites. Carbohydr. Polym. 94, 655-662, (2013). 

Wang, L., Wang, H., Yuan, L., Yang, W, Wu, Z., Chen, H. (2011). Step-wise control of protein adsorption and bacterial attachment on a nanowire array surface tuning surface wettability by salt concentration. Journal of Materials Chemistry, 21, 13920-13925. http //dx.doi.org/10.1039/ClJM12148K. 

Common to DET mechanisms is the necessity of some form of physical contact between the microorganism and the terminal electron acceptor. As Figure 8.3 shows, two possibilities of DET can be distinguished DET via membrane-boimd redox proteins and DET via bacterial pili - so-called nanowires. Recent research indicates that these options likely occur in conjunction, and are mutually dependent to achieve high electron transfer rates. 

Over the last 2 decades, there has been an increasing interest in the development of one-dimensional nanomaterials, such as carbon nanotubes (Ounaies et al., 2003), bacterial nanofibers (Yano et al., 2005), silica nanotubes (Miyaji et al., 2003), and titanium dioxide nanotubes and nanowires (Yuan and Su, 2004). These new materials have relatively large specific surface areas and high aspect ratios hence, they are suitable for use as reinforcements, chemical probes, sensors, hydrogen storage, displays, and templates. One-dimension material/polymer nanocomposites allow us to take advantage of the extraordinary properties of one-dimension nanomaterials. 

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