Authors: Satish Kumar Lodhi, Shikha Gupta
Abstract: Microbial nanowires represent a transformative advancement in bioenergy science, offering a novel mechanism for extracellular electron transport (EET) that can be harnessed for sustainable energy generation. These protein-based conductive filaments, produced by certain electroactive bacteria such as Geobacter and Shewanella species, enable microbes to transfer electrons across cell membranes to external electron acceptors such as metal oxides or electrodes. This unique capability has immense implications for microbial fuel cells (MFCs), bioremediation, and electro-fermentation. Unlike traditional conductive materials, microbial nanowires are biodegradable, self-assembling, and functionally dynamic under ambient environmental conditions. Recent discoveries have revealed the complex structure of nanowires, often comprising multi-heme cytochromes or type IV pili modified with aromatic amino acids, which contribute to long-range electron conductivity. Their integration into bioelectrochemical systems significantly enhances current output and efficiency. This review synthesizes current knowledge of microbial nanowire biology, electrochemical behavior, and engineering strategies to optimize their conductive properties. It also highlights future directions in synthetic biology and materials science for scalable bioenergy solutions. As global energy demands grow, microbial nanowires stand at the forefront of next-generation, eco-friendly energy technologies, bridging the gap between living systems and electrical networks.
DOI: https://doi.org/10.5281/zenodo.16835489
