@article {3065, title = {Intrinsically Conductive Microbial Nanowires for {\textquoteright}Green{\textquoteright} Electronics with Novel Functions.}, journal = {Trends Biotechnol}, volume = {39}, year = {2021}, month = {2021 Sep}, pages = {940-952}, abstract = {

Intrinsically conductive protein nanowires, microbially produced from inexpensive, renewable feedstocks, are a sustainable alternative to traditional nanowire electronic materials, which require high energy inputs and hazardous conditions/chemicals for fabrication and can be highly toxic. Pilin-based nanowires can be tailored for specific functions via the design of synthetic pilin genes to tune wire conductivity or introduce novel functionalities. Other microbially produced nanowire options for electronics may include cytochrome wires, curli fibers, and the conductive fibers of cable bacteria. Proof-of-concept protein nanowire electronics that have been successfully demonstrated include biomedical sensors, neuromorphic devices, and a device that generates electricity from ambient humidity. Further development of applications will require interdisciplinary teams of engineers, biophysicists, and synthetic biologists.

}, keywords = {Electric Conductivity, Electronics, Nanowires, Proteins}, issn = {1879-3096}, doi = {10.1016/j.tibtech.2020.12.005}, author = {Lovley, Derek R and Yao, Jun} } @article {3061, title = {Self-sustained green neuromorphic interfaces.}, journal = {Nat Commun}, volume = {12}, year = {2021}, month = {2021 Jun 07}, pages = {3351}, abstract = {

Incorporating neuromorphic electronics in bioelectronic interfaces can provide intelligent responsiveness to environments. However, the signal mismatch between the environmental stimuli and driving amplitude in neuromorphic devices has limited the functional versatility and energy sustainability. Here we demonstrate multifunctional, self-sustained neuromorphic interfaces by achieving signal matching at the biological level. The advances rely on the unique properties of microbially produced protein nanowires, which enable both bio-amplitude (e.g., <100 mV) signal processing and energy harvesting from ambient humidity. Integrating protein nanowire-based sensors, energy devices and memristors of bio-amplitude functions yields flexible, self-powered neuromorphic interfaces that can intelligently interpret biologically relevant stimuli for smart responses. These features, coupled with the fact that protein nanowires are a green biomaterial of potential diverse functionalities, take the interfaces a step closer to biological integration.

}, keywords = {Biocompatible Materials, Electronics, Nanotechnology, Nanowires, Neural Networks, Computer, Proteins, Synapses}, issn = {2041-1723}, doi = {10.1038/s41467-021-23744-2}, author = {Fu, Tianda and Liu, Xiaomeng and Fu, Shuai and Woodard, Trevor and Gao, Hongyan and Lovley, Derek R and Yao, Jun} } @article {3075, title = {Decorating the Outer Surface of Microbially Produced Protein Nanowires with Peptides.}, journal = {ACS Synth Biol}, volume = {8}, year = {2019}, month = {2019 Aug 16}, pages = {1809-1817}, abstract = {

The potential applications of electrically conductive protein nanowires (e-PNs) harvested from might be greatly expanded if the outer surface of the wires could be modified to confer novel sensing capabilities or to enhance binding to other materials. We developed a simple strategy for functionalizing e-PNs with surface-exposed peptides. The gene for the monomer that assembles into e-PNs was modified to add peptide tags at the carboxyl terminus of the monomer. Strains of were constructed that fabricated synthetic e-PNs with a six-histidine "His-tag" or both the His-tag and a nine-peptide "HA-tag" exposed on the outer surface. Addition of the peptide tags did not diminish e-PN conductivity. The abundance of HA-tag in e-PNs was controlled by placing expression of the gene for the synthetic monomer with the HA-tag under transcriptional regulation. These studies suggest broad possibilities for tailoring e-PN properties for diverse applications.

}, keywords = {Carboxy-Lyases, Ethylene Glycols, Molecular Structure, Nanowires, Oxygenases, Peptides, Phenylalanine Ammonia-Lyase, Plasmids, Proteins, Saccharomyces cerevisiae, Saccharomyces cerevisiae Proteins, Styrenes}, issn = {2161-5063}, doi = {10.1021/acssynbio.9b00131}, author = {Ueki, Toshiyuki and Walker, David J F and Tremblay, Pier-Luc and Nevin, Kelly P and Ward, Joy E and Woodard, Trevor L and Nonnenmann, Stephen S and Lovley, Derek R} } @article {3101, title = {Synthetic Biological Protein Nanowires with High Conductivity.}, journal = {Small}, volume = {12}, year = {2016}, month = {2016 Sep}, pages = {4481-5}, abstract = {

Genetic modification to add tryptophan to PilA, the monomer for the electrically conductive pili of Geobacter sulfurreducens, yields conductive protein filaments 2000-fold more conductive than the wild-type pili while cutting the diameter in half to 1.5 nm.

}, keywords = {Amino Acid Sequence, Electric Conductivity, Fimbriae, Bacterial, Geobacter, Nanowires, Proteins, Tryptophan}, issn = {1613-6829}, doi = {10.1002/smll.201601112}, author = {Tan, Yang and Adhikari, Ramesh Y and Malvankar, Nikhil S and Pi, Shuang and Ward, Joy E and Woodard, Trevor L and Nevin, Kelly P and Xia, Qiangfei and Tuominen, Mark T and Lovley, Derek R} }