Bioinspired Heme Binding Peptide Assemblies—Synthetic Analogs of Electronically Conductive Multiheme Proteins

Anaerobic bacteria cast long, one dimensional, cytochrome rich, nanoscale fibers to transfer electrons over long ranges as part of their respiratory pathway. These fibers were found to be electronically conductive due to the organized network of overlapping heme molecules. Inspired by this phenomenon, a library of synthetic one-dimensional heme binding peptide assemblies has been synthesized and characterized. Although these materials are reminiscent of the naturally occurring multiheme cytochromes, they currently do not possess the same electronically conductive properties. However, due to the synthetic ease of these libraries, the molecular structure of the peptide can be modified to facilitate variations in amino acid and secondary structure content that impact the function of the resulting assemblies. Consequently, the self-assembled peptide product can be tuned to accommodate a multitude of fabrication processes for incorporation into materials and devices. The presentation will highlight the molecular assemblies and the motivation behind their design and briefly introduce our use of machine learning to predict new sequences of heme binding peptide assemblies.