Shallow conductance decay along the heme array of a single tetraheme protein wire

Garg, Kavita, Futera, Zdenek, Wu, Xiaojing, Jeong, Yongchan, Chiu, Rachel, Chittari Pisharam, Varun, Ha, Tracy, Aragones, Albert, van Wonderen, Jessica H., Butt, Julea N. ORCID: https://orcid.org/0000-0002-9624-5226, Blumberger, Jochen and Diez-Perez, Ismael (2024) Shallow conductance decay along the heme array of a single tetraheme protein wire. Chemical Science, 15 (31). pp. 12326-12335. ISSN 2041-6520

[thumbnail of Garg_etal_2024_ ChemSci_d4sc01366b]
Preview
PDF (Garg_etal_2024_ ChemSci_d4sc01366b) - Published Version
Available under License Creative Commons Attribution.

Download (1MB) | Preview

Abstract

Multiheme cytochromes (MHCs) are the building blocks of highly conductive micrometre-long supramolecular wires found in so-called electrical bacteria. Recent studies have revealed that these proteins possess a long supramolecular array of closely packed heme cofactors along the main molecular axis alternating between perpendicular and stacking configurations (TST = T-shaped, Stacked, T-shaped). While TST arrays have been identified as the likely electron conduit, the mechanisms of outstanding long-range charge transport observed in these structures remain unknown. Here we study charge transport on individual small tetraheme cytochromes (STCs) containing a single TST heme array. Individual STCs are trapped in a controllable nanoscale tunnelling gap. By modulating the tunnelling gap separation, we are able to selectively probe four different electron pathways involving 1, 2, 3 and 4 heme cofactors, respectively, leading to the determination of the electron tunnelling decay constant along the TST heme motif. Conductance calculations of selected single-STC junctions are in excellent agreement with experiments and suggest a mechanism of electron tunnelling with shallow length decay constant through an individual STC. These results demonstrate that an individual TST motif supporting electron tunnelling might contribute to a tunnelling-assisted charge transport diffusion mechanism in larger TST associations.

Item Type: Article
Additional Information: Funding information: ID-P, KG, YJ and TH thanks support from the European Research Council (ERC) under the European Union Horizon 2020 Research and Innovation Program (Grant Agreement ERC Fields4CAT-772391) and from UKRI-BBSRC BB/X002810/1. VCP was supported by NMES King's College London Faculty via the Physical Sciences of Life Institute. ACA thanks to the support of the Spanish MICINN with the fellowship RYC2021-031001-I and from the Max Planck Society. JvW and JNB thank EPSRC for funding (Grant EP/M001989/1). RC was supported by the UKRI Biotechnology and Biological Sciences Research Council Norwich Research Park Biosciences Doctoral Training Partnership (Grant number BB/T008717/1). ZF was supported by the Czech Science Foundation (project 20-02067Y) and he is grateful for computational resources provided by the project “e-Infrastruktura CZ” (e-INFRA LM2018140) within the program Projects of Large Research, Development and Innovations Infrastructures. XW was supported by the European Research Council (ERC) under the European Union Horizon 2020 Research and Innovation Program (Grant Agreement ERC 682539/SOFTCHARGE). Via our membership in the UK's HEC Materials Chemistry Consortium, which is funded by EPSRC (Grants EP/L000202 and EP/R029431), this work used the ARCHER UK National Supercomputing Service as well as the UK Materials and Molecular Modelling (MMM) Hub, which is partially funded by EPSRC (Grant EP/P020194), for computational resources.
Faculty \ School: Faculty of Science > School of Biological Sciences
Faculty of Science > School of Chemistry (former - to 2024)
UEA Research Groups: Faculty of Science > Research Groups > Centre for Photonics and Quantum Science
Faculty of Science > Research Groups > Molecular Microbiology
Faculty of Science > Research Groups > Energy Materials Laboratory
Faculty of Science > Research Groups > Chemistry of Light and Energy
Faculty of Science > Research Groups > Chemistry of Life Processes
Faculty of Science > Research Centres > Centre for Molecular and Structural Biochemistry
Related URLs:
Depositing User: LivePure Connector
Date Deposited: 01 Jul 2024 11:33
Last Modified: 18 Nov 2024 12:30
URI: https://ueaeprints.uea.ac.uk/id/eprint/95719
DOI: 10.1039/D4SC01366B

Downloads

Downloads per month over past year

Actions (login required)

View Item View Item