Introduction
All living organisms generate electrochemical gradients over biological membranes, which are fueled by electron flow through metalloproteins. Bacteria have a fascinating ability to use electricity in their metabolism, transferring electrons to and from their environment. This natural process can be captured and manipulated for innovative applications, such as generating electricity in microbial fuel cells and developing advanced biosensors. In this research, I focused on leveraging these unique capabilities of bacteria to create sustainable energy solutions and enhance environmental monitoring.
Shewanella oneidensis MR-1: Enhancing Microbial Fuel Cells with Cisplatin
I worked on an exciting project where we used an anticancer drug, cisplatin, to improve the performance of microbial fuel cells. Cancer cells treated with this DNA-binding drug cannot divide and die. In bacteria, this treatment results in the inability to divide into sister cells, while the cells keep growing, resulting in so-called “spaghetti-like” growth. By treating the bacteria Shewanella oneidensis MR-1 with cisplatin, we discovered that this treatment significantly boosted their electrical communication with the electrodes, leading to up to a five-fold increase in electricity generation! This innovative approach of modifying bacterial cells, rather than focusing on attachment modes, could lead to more efficient bioelectrochemical systems, which is incredibly promising for sustainable energy solutions.
- S. A. Patil, K. Górecki, C. Hägerhäll, L. Gorton Cisplatin-induced elongation of Shewanella oneidensis MR-1 cells improves microbe-electrode interactions for use in microbial fuel cells, (2013) Energy & Environmental Science, 6: 2626-2630. Read
Rhodobacter capsulatus: Wiring for Biofuel Cells and Electrochemical Communication
In our research on the purple bacteria Rhodobacter capsulatus, we explored their potential for use in biofuel cells and microbial biosensors. By using an osmium redox polymer to facilitate electron transfer between the bacteria and electrodes, we achieved impressive results. The wild type strain generated a much better and more stable current compared to a mutant strain lacking the outer capsule. This demonstrated how these versatile bacteria can be effectively used in various electrochemical applications, opening new doors for sustainable energy and environmental monitoring.
Furthermore, we delved into how different growth conditions of Rhodobacter capsulatus impact their ability to communicate with electrodes. Using the same osmium redox polymer, we established a stable and efficient electron transfer system. This study was particularly exciting because it showed the potential of the metabolically versatile Rhodobacter capsulatus in biofuel cells and biosensors, especially for light-driven applications.
- K. Hasan, K.V.R. Reddy, V. Essman, K. Górecki, P. O Conghaile, W. Schuhmmann, D. Leech, C. Hägerhäll, L. Gorton, Electrochemical Communication Between Electrodes and Rhodobacter capsulatus Grown in Different Metabolic Modes, (2015) Electroanalysis 27 (1): 118-127. Read
- K. Hasan, S. A. Patil, K. Górecki, D. Leech, C. Hägerhäll, L. Gorton, Electrochemical communication between heterotrophically grown Rhodobacter capsulatus with electrodes mediated by an osmium redox polymer, (2013) Bioelectrochemistry, pp. 30-36. Read