Coherent Electron Transport across a 3 nm Bioelectronic Junction Made of Multi-Heme Proteins

Zdenek Futera, Ichiro Ide, Ben Kayser, Kavita Garg, Xiuyun Jiang, Jessica H. Van Wonderen, Julea N. Butt, Hisao Ishii, Israel Pecht, Mordechai Sheves, David Cahen, Jochen Blumberger

Research output: Contribution to journalArticlepeer-review

39 Scopus citations

Abstract

Multi-heme cytochromes (MHCs) are fascinating proteins used by bacterial organisms to shuttle electrons within, between, and out of their cells. When placed in solid-state electronic junctions, MHCs support temperature-independent currents over several nanometers that are 3 orders of magnitude higher compared to other redox proteins of similar size. To gain molecular-level insight into their astonishingly high conductivities, we combine experimental photoemission spectroscopy with DFT+ς current-voltage calculations on a representative Gold-MHC-Gold junction. We find that conduction across the dry, 3 nm long protein occurs via off-resonant coherent tunneling, mediated by a large number of protein valence-band orbitals that are strongly delocalized over heme and protein residues. This picture is profoundly different from the electron hopping mechanism induced electrochemically or photochemically under aqueous conditions. Our results imply that the current output in solid-state junctions can be even further increased in resonance, for example, by applying a gate voltage, thus allowing a quantum jump for next-generation bionanoelectronic devices.

Original languageEnglish
Pages (from-to)9766-9774
Number of pages9
JournalJournal of Physical Chemistry Letters
Volume11
Issue number22
DOIs
StatePublished - 19 Nov 2020
Externally publishedYes

Bibliographical note

Publisher Copyright:
© 2020 American Chemical Society.

Funding

Z.F. was supported by EPSRC (EP/M001946/1) and by the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme (grant agreement no. 682539/SOFTCHARGE). X.J. was supported by a Ph.D. studentship cosponsored by the Chinese Scholarship Council and University College London. J.H.v.W. was supported by EPSRC (EP/M001989/1). I.I. and H.I. were supported by JSPS KAKENHI Grant 16H04222. M.S. and D.C. thank the Israel Science Foundation and the German Science Foundation (DFG) for partial support. Via UCL-group membership of the UK’s HEC Materials Chemistry Consortium, which is funded by EPSRC (EP/L000202, EP/R029431), this work used the ARCHER UK National Supercomputing Service ( http://www.archer.ac.uk ). We are grateful to the UK Materials and Molecular Modelling Hub for computational resources, which is partially funded by EPSRC (EP/P020194/1).

FundersFunder number
Chinese Scholarship Council
German Science Foundation
Horizon 2020 Framework Programme682539
Engineering and Physical Sciences Research CouncilEP/M001946/1
University College LondonEP/M001989/1
European Research Council
Deutsche ForschungsgemeinschaftEP/P020194/1, EP/R029431, EP/L000202
Japan Society for the Promotion of Science16H04222
Israel Science Foundation

    Fingerprint

    Dive into the research topics of 'Coherent Electron Transport across a 3 nm Bioelectronic Junction Made of Multi-Heme Proteins'. Together they form a unique fingerprint.

    Cite this