All Climate Events

Thursday, September 17, 2020. 11:00AM. Webinar: Protein Nanowires: Electrification of the Microbial World and Maybe Our Own. Derek Lovley, University of Massachusetts. Register here.

Electrically conductive protein nanowires are widespread in the microbial world and are a revolutionary, ‘green’ material for the fabrication of electronic devices. Protein nanowires have independently evolved multiple times in microbial history to support direct interspecies electron transfer (DIET) and extracellular electron exchange between microbes and insoluble minerals. Electron transfer to Fe(III) and Mn(IV) oxides influences several natural biogeochemical cycles and plays an important role in the bioremediation of toxic organic and metal wastes. Protein nanowires function as electrical connects for DIET in methane-producing communities, routing electrons to microbes that convert carbon dioxide to methane. Artificially enhancing DIET with conductive materials improves the conversion of organic wastes to methane, one of the few successful large-scale bioenergy processes. DIET has also been documented in terrestrial wetlands, an important source of the powerful greenhouse gas methane. Numerous bio electrochemical systems for energy generation and environmental remediation are based on the ability of electroactive microbes to electrically interact with electrodes through protein nanowires and other biologically produced electrical connects. Protein nanowires harvested from microbes have many functional advantages over traditional nanowire materials and are the key components in novel electronic devices designed for sustainable electricity production, neuromorphic memory, and environmental and biomedical sensing. An E. coli chassis for mass production of protein nanowires has been constructed, providing a ready source of material for electronics, as well as for studies on the basic mechanisms for long-range electron transport along protein nanowires. Continued exploration is required to better understand the electrification of microbial communities with microbial nanowires and to expand the ‘green toolbox’ of sustainable electronic materials for wiring and powering the emerging ‘Internet of Things’.