1
|
Selikhanov G, Atamas A, Yukhimchuk D, Fufina T, Vasilieva L, Gabdulkhakov A. Stabilization of Cereibacter sphaeroides Photosynthetic Reaction Center by the Introduction of Disulfide Bonds. MEMBRANES 2023; 13:154. [PMID: 36837657 PMCID: PMC9967408 DOI: 10.3390/membranes13020154] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/29/2022] [Revised: 01/19/2023] [Accepted: 01/23/2023] [Indexed: 06/18/2023]
Abstract
The photosynthetic reaction center of the purple nonsulfur bacterium Cereibacter sphaeroides is a useful model for the study of mechanisms of photoinduced electron transfer and a promising component for photo-bio-electrocatalytic systems. The basic research and technological applications of this membrane pigment-protein complex require effective approaches to increase its structural stability. In this work, a rational design approach to genetically modify the reaction centers by introducing disulfide bonds is used. This resulted in significantly increasing the thermal stability of some of the mutant pigment-protein complexes. The formation of the S-S bonds was confirmed by X-ray crystallography as well as SDS-PAGE, and the optical properties of the reaction centers were studied. The genetically modified reaction centers presented here preserved their ability for photochemical charge separation and could be of interest for basic science and biotechnology.
Collapse
Affiliation(s)
- Georgii Selikhanov
- Institute of Protein Research, Russian Academy of Sciences, Institutskaya 4, 142290 Pushchino, Moscow Region, Russia
- Federal Research Center Pushchino Scientific Center for Biological Research PSCBR, Institute of Basic Biological Problems, Russian Academy of Sciences, Institutskaya 2, 142290 Pushchino, Moscow Region, Russia
| | - Anastasia Atamas
- Institute of Protein Research, Russian Academy of Sciences, Institutskaya 4, 142290 Pushchino, Moscow Region, Russia
| | - Diana Yukhimchuk
- Institute of Protein Research, Russian Academy of Sciences, Institutskaya 4, 142290 Pushchino, Moscow Region, Russia
| | - Tatiana Fufina
- Federal Research Center Pushchino Scientific Center for Biological Research PSCBR, Institute of Basic Biological Problems, Russian Academy of Sciences, Institutskaya 2, 142290 Pushchino, Moscow Region, Russia
| | - Lyudmila Vasilieva
- Federal Research Center Pushchino Scientific Center for Biological Research PSCBR, Institute of Basic Biological Problems, Russian Academy of Sciences, Institutskaya 2, 142290 Pushchino, Moscow Region, Russia
| | - Azat Gabdulkhakov
- Institute of Protein Research, Russian Academy of Sciences, Institutskaya 4, 142290 Pushchino, Moscow Region, Russia
| |
Collapse
|
2
|
Furuya R, Omagari S, Tan Q, Lokstein H, Vacha M. Enhancement of the Photocurrent of a Single Photosystem I Complex by the Localized Plasmon of a Gold Nanorod. J Am Chem Soc 2021; 143:13167-13174. [PMID: 34374520 DOI: 10.1021/jacs.1c04691] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A combination of conductive atomic force microscopy (AFM) and confocal fluorescence microscopy was used to measure photocurrents passing through single trimeric photosytem I (PSI) complexes located in the vicinity of single gold nanorods (AuNRs). Simultaneous excitation of PSI and of the AuNR longitudinal plasmon mode and detection of photocurrents from individual PSI in relation to the position of single AuNRs enable insight into plasmon-induced phenomena that are otherwise inaccessible in ensemble experiments. We have observed photocurrent enhancement by the localized plasmons by a factor of 2.9 on average, with maximum enhancement values of up to 8. Selective excitation of the longitudinal plasmon modes by the polarization of the excitation laser enables controllable switch-on of the photocurrent enhancement. The dependence of the extent of enhancement on the distance between PSI and AuNRs indicates that, apart from the enhancement of absorption, there is an additional enhancement mechanism affecting directly the electron transport process. The present study provides deeper insight into the molecular mechanisms of plasmon-enhanced photocurrents, not only in PSI but also potentially in other systems as well.
Collapse
Affiliation(s)
- Ryotaro Furuya
- Department of Materials Science and Engineering, Tokyo Institute of Technology, Ookayama 2-12-1-S8-44, Meguro-ku, Tokyo 152-8552, Japan
| | - Shun Omagari
- Department of Materials Science and Engineering, Tokyo Institute of Technology, Ookayama 2-12-1-S8-44, Meguro-ku, Tokyo 152-8552, Japan
| | - Qiwen Tan
- Department of Materials Science and Engineering, Tokyo Institute of Technology, Ookayama 2-12-1-S8-44, Meguro-ku, Tokyo 152-8552, Japan
| | - Heiko Lokstein
- Department of Chemical Physics and Optics, Faculty of Mathematics and Physics, Charles University, Ke Karlovu 3, 121 16 Prague, Czech Republic
| | - Martin Vacha
- Department of Materials Science and Engineering, Tokyo Institute of Technology, Ookayama 2-12-1-S8-44, Meguro-ku, Tokyo 152-8552, Japan.,Department of Chemical Physics and Optics, Faculty of Mathematics and Physics, Charles University, Ke Karlovu 3, 121 16 Prague, Czech Republic
| |
Collapse
|
3
|
Stones R, Hossein-Nejad H, van Grondelle R, Olaya-Castro A. On the performance of a photosystem II reaction centre-based photocell. Chem Sci 2017; 8:6871-6880. [PMID: 29147512 PMCID: PMC5636947 DOI: 10.1039/c7sc02983g] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2017] [Accepted: 08/04/2017] [Indexed: 12/26/2022] Open
Abstract
The photosystem II reaction centre is the photosynthetic complex responsible for oxygen production on Earth. Its water splitting function is particularly favoured by the formation of a stable charge separated state via a pathway that starts at an accessory chlorophyll. Here we envision a photovoltaic device that places one of these complexes between electrodes and investigate how the mean current and its fluctuations depend on the microscopic interactions underlying charge separation in the pathway considered. Our results indicate that coupling to well resolved vibrational modes does not necessarily offer an advantage in terms of power output but can lead to photo-currents with suppressed noise levels characterizing a multi-step ordered transport process. Besides giving insight into the suitability of these complexes for molecular-scale photovoltaics, our work suggests a new possible biological function for the vibrational environment of photosynthetic reaction centres, namely, to reduce the intrinsic current noise for regulatory processes.
Collapse
Affiliation(s)
- Richard Stones
- Department of Physics and Astronomy , University College London , Gower Street , London , WC1E 6BT , UK .
| | - Hoda Hossein-Nejad
- Department of Physics and Astronomy , University College London , Gower Street , London , WC1E 6BT , UK .
| | - Rienk van Grondelle
- Department of Physics and Astronomy , VU University , 1081 HV Amsterdam , The Netherlands
| | - Alexandra Olaya-Castro
- Department of Physics and Astronomy , University College London , Gower Street , London , WC1E 6BT , UK .
| |
Collapse
|
4
|
Kamran M, Akkilic N, Luo J, Abbasi AZ. RETRACTED: Monolayers of pigment-protein complexes on a bare gold electrode: Orientation controlled deposition and comparison of electron transfer rate for two configurations. Biosens Bioelectron 2015; 69:40-5. [DOI: 10.1016/j.bios.2015.01.063] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2014] [Revised: 01/10/2015] [Accepted: 01/26/2015] [Indexed: 11/30/2022]
|
5
|
Castañeda Ocampo OE, Gordiichuk P, Catarci S, Gautier DA, Herrmann A, Chiechi RC. Mechanism of Orientation-Dependent Asymmetric Charge Transport in Tunneling Junctions Comprising Photosystem I. J Am Chem Soc 2015; 137:8419-27. [PMID: 26057523 PMCID: PMC4558993 DOI: 10.1021/jacs.5b01241] [Citation(s) in RCA: 49] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Recently, photoactive proteins have gained a lot of attention due to their incorporation into bioinspired (photo)electrochemical and solar cells. This paper describes the measurement of the asymmetry of current transport of self-assembled monolayers (SAMs) of the entire photosystem I (PSI) protein complex (not the isolated reaction center, RCI), on two different "director SAMs" supported by ultraflat Au substrates. The director SAMs induce the preferential orientation of PSI, which manifest as asymmetry in tunneling charge-transport. We measured the oriented SAMs of PSI using eutectic Ga-In (EGaIn), a large-area technique, and conducting probe atomic force microscopy (CP-AFM), a single-complex technique, and determined that the transport properties are comparable. By varying the temperatures at which the measurements were performed, we found that there is no measurable dependence of the current on temperature from ±0.1 to ±1.0 V bias, and thus, we suggest tunneling as the mechanism for transport; there are no thermally activated (e.g., hopping) processes. Therefore, it is likely that relaxation in the electron transport chain is not responsible for the asymmetry in the conductance of SAMs of PSI complexes in these junctions, which we ascribe instead to the presence of a large, net dipole moment present in PSI.
Collapse
Affiliation(s)
- Olga E Castañeda Ocampo
- †Stratingh Institute for Chemistry, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands.,‡Zernike Institute for Advanced Materials, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands
| | - Pavlo Gordiichuk
- ‡Zernike Institute for Advanced Materials, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands
| | - Stefano Catarci
- ‡Zernike Institute for Advanced Materials, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands
| | - Daniel A Gautier
- ‡Zernike Institute for Advanced Materials, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands
| | - Andreas Herrmann
- ‡Zernike Institute for Advanced Materials, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands
| | - Ryan C Chiechi
- †Stratingh Institute for Chemistry, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands.,‡Zernike Institute for Advanced Materials, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands
| |
Collapse
|
6
|
Kamran M, Friebe VM, Delgado JD, Aartsma TJ, Frese RN, Jones MR. Demonstration of asymmetric electron conduction in pseudosymmetrical photosynthetic reaction centre proteins in an electrical circuit. Nat Commun 2015; 6:6530. [PMID: 25751412 PMCID: PMC4366537 DOI: 10.1038/ncomms7530] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2014] [Accepted: 02/04/2015] [Indexed: 12/22/2022] Open
Abstract
Photosynthetic reaction centres show promise for biomolecular electronics as nanoscale solar-powered batteries and molecular diodes that are amenable to atomic-level re-engineering. In this work the mechanism of electron conduction across the highly tractable Rhodobacter sphaeroides reaction centre is characterized by conductive atomic force microscopy. We find, using engineered proteins of known structure, that only one of the two cofactor wires connecting the positive and negative termini of this reaction centre is capable of conducting unidirectional current under a suitably oriented bias, irrespective of the magnitude of the bias or the applied force at the tunnelling junction. This behaviour, strong functional asymmetry in a largely symmetrical protein–cofactor matrix, recapitulates the strong functional asymmetry characteristic of natural photochemical charge separation, but it is surprising given that the stimulus for electron flow is simply an externally applied bias. Reasons for the electrical resistance displayed by the so-called B-wire of cofactors are explored. Photosynthetic reaction centres have been proposed for applications in bioelectronics. Here, the authors examine electron transport through the reaction centre from R. sphaeroides using conductive AFM, observing asymmetric conductance along only one cofactor wire under an applied bias.
Collapse
Affiliation(s)
- Muhammad Kamran
- Leiden Institute of Physics, Leiden University, Niels Bohrweg 2, 2333 CA Leiden, The Netherlands
| | - Vincent M Friebe
- Department of Physics and Astronomy, LaserLaB Amsterdam, VU University Amsterdam, De Boelelaan 1081, 1081 HV Amsterdam, The Netherlands
| | - Juan D Delgado
- Department of Physics and Astronomy, LaserLaB Amsterdam, VU University Amsterdam, De Boelelaan 1081, 1081 HV Amsterdam, The Netherlands
| | - Thijs J Aartsma
- Leiden Institute of Physics, Leiden University, Niels Bohrweg 2, 2333 CA Leiden, The Netherlands
| | - Raoul N Frese
- Department of Physics and Astronomy, LaserLaB Amsterdam, VU University Amsterdam, De Boelelaan 1081, 1081 HV Amsterdam, The Netherlands
| | - Michael R Jones
- School of Biochemistry, University of Bristol, Medical Sciences Building, University Walk, Bristol BS8 1TD, UK
| |
Collapse
|
7
|
Kamran M, Delgado JD, Friebe V, Aartsma TJ, Frese RN. Photosynthetic Protein Complexes as Bio-photovoltaic Building Blocks Retaining a High Internal Quantum Efficiency. Biomacromolecules 2014; 15:2833-8. [DOI: 10.1021/bm500585s] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Affiliation(s)
- Muhammad Kamran
- Leiden
Institute of Physics, Leiden University, Niels Bohrweg 2, 2333CA Leiden, The Netherlands
| | - Juan D. Delgado
- VU University, De Boelelaan 1081, 1081HV Amsterdam, The Netherlands
| | - Vincent Friebe
- VU University, De Boelelaan 1081, 1081HV Amsterdam, The Netherlands
| | - Thijs J. Aartsma
- Leiden
Institute of Physics, Leiden University, Niels Bohrweg 2, 2333CA Leiden, The Netherlands
| | - Raoul N. Frese
- VU University, De Boelelaan 1081, 1081HV Amsterdam, The Netherlands
| |
Collapse
|
8
|
|
9
|
Yaghoubi H, Jun D, Beatty JT, Takshi A. Photosynthetic Reaction Center Immobilization through Carboxylic Acid Terminated\Cytochrome C Linker for Applications in Photoprotein-based Bio-photovoltaic Devices. ACTA ACUST UNITED AC 2013. [DOI: 10.1557/opl.2013.682] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
ABSTRACTBacterial photosynthetic reaction centers (RCs) are promising materials for solar energy harvesting, due to their high internal quantum efficiency. However, applications of RCs in bio-photovoltaic devices so far show relatively low external power conversion efficiency, mainly due to low efficiency of the charge transfer to the electrode. Preferential orientation of RCs on an electrode’s surface can enhance the charge transfer rate to some extent. Yet, the results of direct coupling of RCs to an Au electrode, through cysteine residues from the H-subunit, revealed that direct electron transfer is not efficient. This work focuses on a different approach to achieve high charge transfer rate between an Au electrode and RC protein complexes by employing cytochrome c (Cyt c)\carboxylic acid-terminated linker molecules. This approach preferentially orients RCs with the primary donor site to the electrode. Furthermore, Cyt c can be considered as a conductive linker, while the charge transfer mechanism through carboxylic acid-terminated linker molecules is dominated by tunneling. The photochronoamperometric results for a two electrode cell setup indicated a 156 nA.cm-2 cathodic photocurrent density; the photocurrent was measured in an electrochemical cell with ubiquinone-10 (Q2) in the electrolyte. Negligible photocurrents were observed in the case of coupled RCs to the Au via cysteine residues on H-subunit, with only Cyt c in the electrolyte. These findings contribute to the design of highly efficient bio-photovoltaic devices.
Collapse
|
10
|
Sumino A, Dewa T, Sasaki N, Kondo M, Nango M. Electron Conduction and Photocurrent Generation of a Light-Harvesting/Reaction Center Core Complex in Lipid Membrane Environments. J Phys Chem Lett 2013; 4:1087-1092. [PMID: 26282025 DOI: 10.1021/jz301976z] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
To reveal the structure-function relationship of membrane proteins, a membrane environment is often used to establish a suitable platform for assembly, functioning, and measurements. The control of the orientation of membrane proteins is the main challenge. In this study, the electron conductivity and photocurrent of a light-harvesting/reaction center core complex (LH1-RC) embedded in a lipid membrane were measured using conductive atomic force microscopy (C-AFM) and photoelectrochemical analysis. AFM topographs showed that LH1-RC molecules were well-orientated, with their H-subunits toward the membrane surface. Rectified conductivity was observed in LH1-RC under precise control of the applied force on the probe electrode (<600 pN). LH1-RC embedded in a membrane generated photocurrent upon irradiation when assembled on an electrode. The observed action spectrum was consistent with the absorption spectrum of LH1-RC. The control of the orientation of LH1-RC by lipid membranes provided well-defined conductivity and photocurrent.
Collapse
Affiliation(s)
- Ayumi Sumino
- †Department of Frontier Materials, Graduate School of Engineering, Nagoya Institute of Technology, Gokiso-cho, Showa-ku, Nagoya 466-8555, Japan
| | - Takehisa Dewa
- †Department of Frontier Materials, Graduate School of Engineering, Nagoya Institute of Technology, Gokiso-cho, Showa-ku, Nagoya 466-8555, Japan
- ‡PRESTO/JST, 4-1-8 Honcho Kawaguchi, Saitama 332-0012, Japan
| | - Nobuaki Sasaki
- †Department of Frontier Materials, Graduate School of Engineering, Nagoya Institute of Technology, Gokiso-cho, Showa-ku, Nagoya 466-8555, Japan
| | - Masaharu Kondo
- †Department of Frontier Materials, Graduate School of Engineering, Nagoya Institute of Technology, Gokiso-cho, Showa-ku, Nagoya 466-8555, Japan
| | - Mamoru Nango
- †Department of Frontier Materials, Graduate School of Engineering, Nagoya Institute of Technology, Gokiso-cho, Showa-ku, Nagoya 466-8555, Japan
| |
Collapse
|
11
|
Gerster D, Reichert J, Bi H, Barth JV, Kaniber SM, Holleitner AW, Visoly-Fisher I, Sergani S, Carmeli I. Photocurrent of a single photosynthetic protein. NATURE NANOTECHNOLOGY 2012; 7:673-6. [PMID: 23023644 DOI: 10.1038/nnano.2012.165] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/29/2012] [Accepted: 08/28/2012] [Indexed: 05/03/2023]
Abstract
Photosynthesis is used by plants, algae and bacteria to convert solar energy into stable chemical energy. The initial stages of this process--where light is absorbed and energy and electrons are transferred--are mediated by reaction centres composed of chlorophyll and carotenoid complexes. It has been previously shown that single small molecules can be used as functional components in electric and optoelectronic circuits, but it has proved difficult to control and probe individual molecules for photovoltaic and photoelectrochemical applications. Here, we show that the photocurrent generated by a single photosynthetic protein-photosystem I-can be measured using a scanning near-field optical microscope set-up. One side of the protein is anchored to a gold surface that acts as an electrode, and the other is contacted by a gold-covered glass tip. The tip functions as both counter electrode and light source. A photocurrent of ∼10 pA is recorded from the covalently bound single-protein junctions, which is in agreement with the internal electron transfer times of photosystem I.
Collapse
Affiliation(s)
- Daniel Gerster
- Physik-Department E20, Technische Universität München, James-Franck Strasse, D-85748 Garching, Germany
| | | | | | | | | | | | | | | | | |
Collapse
|
12
|
Chen YS, Hong MY, Huang GS. A protein transistor made of an antibody molecule and two gold nanoparticles. NATURE NANOTECHNOLOGY 2012; 7:197-203. [PMID: 22367097 DOI: 10.1038/nnano.2012.7] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/27/2011] [Accepted: 01/10/2012] [Indexed: 05/11/2023]
Abstract
A major challenge in molecular electronics is to attach electrodes to single molecules in a reproducible manner to make molecular junctions that can be operated as transistors. Several attempts have been made to attach electrodes to proteins, but these devices have been unstable. Here, we show that self-assembly can be used to fabricate, in a highly reproducible manner, molecular junctions in which an antibody molecule (immunoglobulin G) binds to two gold nanoparticles, which in turn are connected to source and drain electrodes. We also demonstrate effective gating of the devices with an applied voltage, and show that the charge transport characteristics of these protein transistors are caused by conformational changes in the antibody. Moreover, by attaching CdSe quantum dots to the antibody, we show that the protein transistor can also be gated by an applied optical field. This approach offers a versatile platform for investigations of single-molecule-based biological functions and might also lead to the large-scale manufacture of integrated bioelectronic circuits.
Collapse
Affiliation(s)
- Yu-Shiun Chen
- Biomedical Electronics Translational Research Center, National Chiao Tung University, 1001 University Road, Hsinchu, Taiwan, ROC [corrected]
| | | | | |
Collapse
|
13
|
Kondo M, Iida K, Dewa T, Tanaka H, Ogawa T, Nagashima S, Nagashima KVP, Shimada K, Hashimoto H, Gardiner AT, Cogdell RJ, Nango M. Photocurrent and electronic activities of oriented-His-tagged photosynthetic light-harvesting/reaction center core complexes assembled onto a gold electrode. Biomacromolecules 2012; 13:432-8. [PMID: 22239547 DOI: 10.1021/bm201457s] [Citation(s) in RCA: 66] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A polyhistidine (His) tag was fused to the C- or N-terminus of the light-harvesting (LH1)-α chain of the photosynthetic antenna core complex (LH1-RC) from Rhodobacter sphaeroides to allow immobilization of the complex on a solid substrate with defined orientation. His-tagged LH1-RCs were adsorbed onto a gold electrode modified with Ni-NTA. The LH1-RC with the C-terminal His-tag (C-His LH1-RC) on the modified electrode produced a photovoltaic response upon illumination. Electron transfer is unidirectional within the RC and starts when the bacteriochlorophyll a dimer in the RC is activated by light absorbed by LH1. The LH1-RC with the N-terminal His-tag (N-His LH1-RC) produced very little or no photocurrent upon illumination at any wavelength. The conductivity of the His-tagged LH1-RC was measured with point-contact current imaging atomic force microscopy, indicating that 60% of the C-His LH1-RC are correctly oriented (N-His 63%). The oriented C-His LH1-RC or N-His LH1-RC showed semiconductive behavior, that is, had the opposite orientation. These results indicate that the His-tag successfully controlled the orientation of the RC on the solid substrate, and that the RC produced photocurrent depending upon the orientation on the electrode.
Collapse
Affiliation(s)
- Masaharu Kondo
- Department of Frontier Materials, Tsukuri College, Graduate School of Engineering, Nagoya Institute of Technology , Gokiso-cho, Showa-ku, Nagoya 466-8555, Japan
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
14
|
den Hollander MJ, Magis JG, Fuchsenberger P, Aartsma TJ, Jones MR, Frese RN. Enhanced photocurrent generation by photosynthetic bacterial reaction centers through molecular relays, light-harvesting complexes, and direct protein-gold interactions. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2011; 27:10282-10294. [PMID: 21728318 DOI: 10.1021/la2013528] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
The utilization of proteins as nanodevices for solar cells, bioelectronics, and sensors generally necessitates the transfer of electrons to or from a conducting material. Here we report on efforts to maximize photocurrent generation by bacterial photosynthetic reaction center pigment-protein complexes (RCs) interfaced with a metal electrode. The possibility of adhering RCs to a bare gold electrode was investigated with a view to minimizing the distance for electron tunneling between the protein-embedded electron-transfer cofactors and the metal surface. Substantial photocurrents were achieved despite the absence of coating layers on the electrode or engineered linkers to achieve the oriented deposition of RCs on the surface. Comparison with SAM-covered gold electrodes indicating enhanced photocurrent densities was achieved because of the absence of an insulating layer between the photoactive pigments and the metal. Utilizing RCs surrounded by light-harvesting 1 complex resulted in higher photocurrents, surprisingly not due to enhanced photoabsorption but likely due to better surface coverage of uniformly oriented RC-LH1 complexes and the presence of a tetraheme cytochrome that could act as a connecting wire. The introduction of cytochrome-c (cyt-c) as a molecular relay also produced increases in current, probably by intercalating between the adhered RCs or RC-LH1 complexes and the electrode to mediate electron transfer. Varying the order in which components were introduced to the electrode indicated that dynamic rearrangements of RCs and cyt-c occurred at the bare metal surface. An upper limit for current generation could not be detected within the range of the illumination power available, with the maximum current density achieved by RC-LH1 complexes being on the order of 25 μA/cm(2). High currents could be generated consecutively for several hours or days under ambient conditions.
Collapse
Affiliation(s)
- Mart-Jan den Hollander
- Biophysics, Faculty of Mathematics and Natural Sciences, Leiden University, P.O. Box 9502, 2300RA Leiden, The Netherlands
| | | | | | | | | | | |
Collapse
|
15
|
Zhang Y, LaFountain AM, Magdaong N, Fuciman M, Allen JP, Frank HA, Rusling JF. Thin Film Voltammetry of Wild Type and Mutant Reaction Center Proteins from Photosynthetic Bacteria. J Phys Chem B 2011; 115:3226-32. [PMID: 21384836 DOI: 10.1021/jp111680p] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Yun Zhang
- Department of Chemistry, University of Connecticut, Storrs, Connecticut 06269, United States
| | - Amy M. LaFountain
- Department of Chemistry, University of Connecticut, Storrs, Connecticut 06269, United States
| | - Nikki Magdaong
- Department of Chemistry, University of Connecticut, Storrs, Connecticut 06269, United States
| | - Marcel Fuciman
- Department of Chemistry, University of Connecticut, Storrs, Connecticut 06269, United States
| | - James P. Allen
- Department of Chemistry and Biochemistry, Arizona State University, Tempe, Arizona 85287, United States
| | - Harry A. Frank
- Department of Chemistry, University of Connecticut, Storrs, Connecticut 06269, United States
| | - James F. Rusling
- Department of Chemistry, University of Connecticut, Storrs, Connecticut 06269, United States
- Department of Cell Biology, University of Connecticut Health Center, Farmington, Connecticut 06032, United States
| |
Collapse
|
16
|
Ron I, Pecht I, Sheves M, Cahen D. Proteins as solid-state electronic conductors. Acc Chem Res 2010; 43:945-53. [PMID: 20329769 DOI: 10.1021/ar900161u] [Citation(s) in RCA: 95] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Protein structures can facilitate long-range electron transfer in solution. But a fundamental question remains: can these structures also serve as solid-state electronic conductors? Answering this question requires methods for studying conductivity of the "dry" protein (which only contains tightly bound structured water molecules) sandwiched between two electronic conductors in a solid-state type configuration. If successful, such systems could serve as the basis for future, bioinspired electronic device technology. In this Account, we survey, analyze, and compare macroscopic and nanoscopic (scanning probe) solid-state conductivities of proteins, noting the inherent constraints of each of these, and provide the first status report on this research area. This analysis shows convincing evidence that "dry" proteins pass orders of magnitude higher currents than saturated molecules with comparable thickness and that proteins with known electrical activity show electronic conductivity, nearly comparable to that of conjugated molecules ("wires"). These findings suggest that the structural features of proteins must have elements that facilitate electronic conductivity, even if they do not have a known electron transfer function. As a result, proteins could serve not only as sensing, polar,or photoactive elements in devices (such as field-effect transistor configurations) but also as electronic conductors. Current knowledge of peptide synthesis and protein modification paves the way toward a greater understanding of how changes in a protein's structure affect its conductivity. Such an approach could minimize the need for biochemical cascades in systems such as enzyme-based circuits, which transduce the protein's response to electronic current. In addition, as precision and sensitivity of solid-state measurements increase, and as knowledge of the structure and function of "dry" proteins grows, electronic conductivity may become an additional approach to study electron transfer in proteins and solvent effects without the introduction of donor or acceptor moieties. We are particularly interested in whether evolution might have prompted the electronic carrier transport capabilities of proteins for which no electrically active function is known in their native biological environment and anticipate that further research may help address this fascinating question.
Collapse
Affiliation(s)
- Izhar Ron
- Materials & Interfaces, Immunology and Organic Chemistry Departments, Weizmann Institute of Science, Rehovot, Israel 76100
| | - Israel Pecht
- Materials & Interfaces, Immunology and Organic Chemistry Departments, Weizmann Institute of Science, Rehovot, Israel 76100
| | - Mordechai Sheves
- Materials & Interfaces, Immunology and Organic Chemistry Departments, Weizmann Institute of Science, Rehovot, Israel 76100
| | - David Cahen
- Materials & Interfaces, Immunology and Organic Chemistry Departments, Weizmann Institute of Science, Rehovot, Israel 76100
| |
Collapse
|
17
|
Ron I, Sepunaru L, Itzhakov S, Belenkova T, Friedman N, Pecht I, Sheves M, Cahen D. Proteins as electronic materials: electron transport through solid-state protein monolayer junctions. J Am Chem Soc 2010; 132:4131-40. [PMID: 20210314 DOI: 10.1021/ja907328r] [Citation(s) in RCA: 142] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Electron transfer (ET) through proteins, a fundamental element of many biochemical reactions, is studied intensively in aqueous solutions. Over the past decade, attempts were made to integrate proteins into solid-state junctions in order to study their electronic conductance properties. Most such studies to date were conducted with one or very few molecules in the junction, using scanning probe techniques. Here we present the high-yield, reproducible preparation of large-area monolayer junctions, assembled on a Si platform, of proteins of three different families: azurin (Az), a blue-copper ET protein, bacteriorhodopsin (bR), a membrane protein-chromophore complex with a proton pumping function, and bovine serum albumin (BSA). We achieve highly reproducible electrical current measurements with these three types of monolayers using appropriate top electrodes. Notably, the current-voltage (I-V) measurements on such junctions show relatively minor differences between Az and bR, even though the latter lacks any known ET function. Electron Transport (ETp) across both Az and bR is much more efficient than across BSA, but even for the latter the measured currents are higher than those through a monolayer of organic, C18 alkyl chains that is about half as wide, therefore suggesting transport mechanism(s) different from the often considered coherent mechanism. Our results show that the employed proteins maintain their conformation under these conditions. The relatively efficient ETp through these proteins opens up possibilities for using such biomolecules as current-carrying elements in solid-state electronic devices.
Collapse
Affiliation(s)
- Izhar Ron
- Departments of Materials and Interfaces, Weizmann Institute of Science, POB 26, Rehovot 76100, Israel
| | | | | | | | | | | | | | | |
Collapse
|