Metamorphosis of pathogen to electrigen at the electrode/electrolyte interface: Direct electron transfer of Staphylococcus aureus leading to superior electrocatalytic activity

• Published in: Electrochemistry communications Vol. 34; pp. 25 - 28
• Main Authors: A., Bhuvaneswari, R., Navanietha Krishnaraj, Berchmans, Sheela
• Format: Journal Article
• Language: English
• Published: Lausanne Elsevier B.V 01.09.2013; Amsterdam Elsevier; New York, NY
• Subjects: Applied sciences; Bioelectricity; Biological and medical sciences; Biotechnology; Cellulose; Electrochemistry; Energy; Energy. Thermal use of fuels; Equipments for energy generation and conversion: thermal, electrical, mechanical energy, etc; Exact sciences and technology; Fuel cells; Fundamental and applied biological sciences. Psychology; Industrial applications and implications. Economical aspects; Microbial electrocatalysis; Microbial fuel cell; Miscellaneous; Molecular biophysics; Physical chemistry in biology; Microbial electrocatalysis; Microbial fuel cell; Cellulose; Bioelectricity; Phosphates; Biological fluid; Ruminant animal; Electrode electrolyte interface; Electron transfer; Surface structure; Cyclic voltammetry; Electrocatalysis; Pathogenic; Bacteria; Micrococcales; Micrococcaceae; Oxidation; Staphylococcus aureus; Modified material; Stomach; Scanning electron microscopy; Porous electrode; Buffer solution; Carbon; Morphology; Biofilm
• ISSN: 1388-2481; 1873-1902
• DOI: 10.1016/j.elecom.2013.05.013

In this paper, we report that Staphylococcus aureus isolated from the rumen fluid can display direct electron transfer on carbon felt electrodes and exhibit enhanced microbial electrocatalysis towards the oxidation of complex substrate like cellulose. The phenomena of direct electron transfer and electrocatalysis were investigated in detail by cyclic voltammentry and chronoamperometry. The electron transfer was closer to perfect reversibility with a peak separation value of only 7mV at a scan rate of 50mV/s. The enhanced microbial electrocatalysis towards the oxidation of cellulose revealed the potential of the microorganism for application in microbial fuel cells. The pure cultures of S. aureus produced an electrocatalytic current density of 1.4mA/cm2 as estimated by long-term chronoamperometry for a cellulose concentration of 20mM. To the best of our knowledge we report for the first time the use of S. aureus for bioelectricity generation with cellulose as a sole source of electron donor. •Pathogenic Staphylococcus aureus, as an electrigen at the electrode interface.•Biofilms utilize carbon felt electrodes as electron acceptors for respiration.•Enhanced microbial electrocatalysis for complex substrates like cellulose.