1
|
Sil D, Khan FST, Rath SP. Effect of intermacrocyclic interactions: Modulation of metal spin-state in oxo/hydroxo/fluoro-bridged diiron(III)/dimanganese(III) porphyrin dimers. ADVANCES IN INORGANIC CHEMISTRY 2023. [DOI: 10.1016/bs.adioch.2022.08.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
|
2
|
Khan FST, Samanta D, Chandel D, Shah SJ, Rath SP. Heme-Heme Interactions in Diheme Cytochromes: Effect of Mixed-Axial Ligation on the Electronic Structure and Electrochemical Properties. Inorg Chem 2021; 60:12870-12882. [PMID: 34370470 DOI: 10.1021/acs.inorgchem.1c01215] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Diheme cytochromes, the simplest members in the multiheme family, play substantial biochemical roles in enzymatic catalysis as well as in electron transfer. A series of diiron(III) porphyrin dimers have been synthesized as active site analogues of diheme cytochromes. The complexes contain six-coordinated iron(III) having thiophenol and imidazole at the fifth and sixth coordination sites, respectively. The iron centers in the complexes have been found to be in a low-spin state, as confirmed through solid-state Mössbauer and electron paramagnetic resonance (EPR) spectroscopic investigations. Mössbauer quadrupole splitting of complexes having mixed ligands is substantially larger than that observed when both axial ligands are the same. Rhombic types of EPR spectra with narrow separation between gx, gy, and gz clearly distinguish heme thiolate coordination compared to bis(imidazole)-ligated low-spin heme centers. The redox potential in diheme cytochromes has been found to be tuned by interheme interactions along with the nature of axial ligands. The effect of mixed-axial ligation within the diiron(III) porphyrin dimers is demonstrated by a positive shift in the Fe(III)/Fe(II) redox couple upon thiophenolate coordination compared to their bis(imidazole) analogues. The pKa of the imidazole also decides the extent of the shift for the Fe(III)/Fe(II) couple, while the potential of the mixed-ligated diiron(III) porphyrin dimer is more positive compared to their monomeric analogue. A variation of around 1.1 V for the Fe(III)/Fe(II) redox potential in the diiron(III) porphyrin dimer can be achieved with the combined effect of axial ligation and a metal spin state, while such a large variation in the redox potential, compared to their monomeric analogues, is attributed to the heme-heme interactions observed in dihemes. Moreover, theoretical calculations also support the experimental shifts in the redox potential values.
Collapse
Affiliation(s)
| | - Deepannita Samanta
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur 208016, India
| | - Dolly Chandel
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur 208016, India
| | - Syed Jehanger Shah
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur 208016, India
| | - Sankar Prasad Rath
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur 208016, India
| |
Collapse
|
3
|
Blake RC, Shively JE, Timkovich R, White RA. Homogeneous Cytochrome 579 Is an Octamer That Reacts Too Slowly With Soluble Iron to Be the Initial Iron Oxidase in the Respiratory Chain of Leptospirillum ferriphilum. Front Microbiol 2021; 12:673066. [PMID: 34012429 PMCID: PMC8126622 DOI: 10.3389/fmicb.2021.673066] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2021] [Accepted: 04/13/2021] [Indexed: 11/20/2022] Open
Abstract
The exact role that cytochrome 579 plays in the aerobic iron respiratory chain of Leptospirillum ferriphilum is unclear. This paper presents genomic, structural, and kinetic data on the cytochrome 579 purified from cell-free extracts of L. ferriphilum cultured on soluble iron. Electrospray mass spectrometry of electrophoretically homogeneous cytochrome 579 yielded two principal peaks at 16,015 and 16,141 Daltons. N-terminal amino acid sequencing of the purified protein yielded data that were used to determine the following: there are seven homologs of cytochrome 579; each homolog possesses the CXXCH heme-binding motif found in c-type cytochromes; each of the seven sequenced strains of L. ferriphilum expresses only two of the seven homologs of the cytochrome; and each homolog contains an N-terminal signal peptide that directs the mature protein to an extra-cytoplasmic location. Static light scattering and macroion mobility measurements on native cytochrome 579 yielded masses of 125 and 135 kDaltons, respectively. The reduced alkaline pyridine hemochromogen spectrum of the purified cytochrome had an alpha absorbance maximum at 567 nm, a property not exhibited by any known heme group. The iron-dependent reduction and oxidation of the octameric cytochrome exhibited positively cooperative kinetic behavior with apparent Hill coefficients of 5.0 and 3.7, respectively, when the purified protein was mixed with mM concentrations of soluble iron. Consequently, the extrapolated rates of reduction at sub-mM iron concentrations were far too slow for cytochrome 579 to be the initial iron oxidase in the aerobic respiratory chain of L. ferriphilum. Rather, these observations support the hypothesis that the acid-stable cytochrome 579 is a periplasmic conduit of electrons from initial iron oxidation in the outer membrane of this Gram-negative bacterium to a terminal oxidase in the plasma membrane.
Collapse
Affiliation(s)
- Robert C Blake
- Division of Basic Pharmaceutical Sciences, Xavier University of Louisiana, New Orleans, LA, United States
| | - John E Shively
- Division of Immunology, Beckman Research Institute of the City of Hope, Duarte, CA, United States
| | - Russell Timkovich
- Department of Chemistry, University of Alabama, Tuscaloosa, AL, United States
| | - Richard Allen White
- Department of Bioinformatics and Genomics, University of North Carolina, Charlotte, NC, United States.,Department of Bioinformatics and Genomics, University of North Carolina, Kannapolis, NC, United States.,Australian Centre for Astrobiology, University of New South Wales, Sydney, NSW, Australia
| |
Collapse
|
4
|
Singh AK, Rath SP. Intermacrocyclic Interactions upon Stepwise Oxidations in a Monometallic Porphyrin Dimer: Ring versus Metal‐Center Oxidations and Effect of Counter Anions. Chemistry 2020; 26:14405-14418. [DOI: 10.1002/chem.202002188] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2020] [Revised: 06/15/2020] [Indexed: 12/22/2022]
Affiliation(s)
- Akhil Kumar Singh
- Department of Chemistry Indian Institute of Technology Kanpur Kanpur 208016 India
| | - Sankar Prasad Rath
- Department of Chemistry Indian Institute of Technology Kanpur Kanpur 208016 India
| |
Collapse
|
5
|
Lam BR, Barr CR, Rowe AR, Nealson KH. Differences in Applied Redox Potential on Cathodes Enrich for Diverse Electrochemically Active Microbial Isolates From a Marine Sediment. Front Microbiol 2019; 10:1979. [PMID: 31555224 PMCID: PMC6724507 DOI: 10.3389/fmicb.2019.01979] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2019] [Accepted: 08/12/2019] [Indexed: 01/21/2023] Open
Abstract
The diversity of microbially mediated redox processes that occur in marine sediments is likely underestimated, especially with respect to the metabolisms that involve solid substrate electron donors or acceptors. Though electrochemical studies that utilize poised potential electrodes as a surrogate for solid substrate or mineral interactions have shed some much needed light on these areas, these studies have traditionally been limited to one redox potential or metabolic condition. This work seeks to uncover the diversity of microbes capable of accepting cathodic electrons from a marine sediment utilizing a range of redox potentials, by coupling electrochemical enrichment approaches to microbial cultivation and isolation techniques. Five lab-scale three-electrode electrochemical systems were constructed, using electrodes that were initially incubated in marine sediment at cathodic or electron-donating voltages (five redox potentials between -400 and -750 mV versus Ag/AgCl) as energy sources for enrichment. Electron uptake was monitored in the laboratory bioreactors and linked to the reduction of supplied terminal electron acceptors (nitrate or sulfate). Enriched communities exhibited differences in community structure dependent on poised redox potential and terminal electron acceptor used. Further cultivation of microbes was conducted using media with reduced iron (Fe0, FeCl2) and sulfur (S0) compounds as electron donors, resulting in the isolation of six electrochemically active strains. The isolates belong to the genera Vallitalea of the Clostridia, Arcobacter of the Epsilonproteobacteria, Desulfovibrio of the Deltaproteobacteria, and Vibrio and Marinobacter of the Gammaproteobacteria. Electrochemical characterization of the isolates with cyclic voltammetry yielded a wide range of midpoint potentials (99.20 to -389.1 mV versus Ag/AgCl), indicating diverse metabolic pathways likely support the observed electron uptake. Our work demonstrates culturing under various electrochemical and geochemical regimes allows for enhanced cultivation of diverse cathode-oxidizing microbes from one environmental system. Understanding the mechanisms of solid substrate oxidation from environmental microbes will further elucidation of the ecological relevance of these electron transfer interactions with implications for microbe-electrode technologies.
Collapse
Affiliation(s)
- Bonita R. Lam
- Department of Biological Sciences, University of Southern California, Los Angeles, CA, United States
| | - Casey R. Barr
- Department of Earth Sciences, University of Southern California, Los Angeles, CA, United States
| | - Annette R. Rowe
- Department of Biological Sciences, University of Cincinnati, Cincinnati, OH, United States
| | - Kenneth H. Nealson
- Department of Biological Sciences, University of Southern California, Los Angeles, CA, United States
- Department of Earth Sciences, University of Southern California, Los Angeles, CA, United States
| |
Collapse
|
6
|
Lebègue E, Costa NL, Fonseca BM, Louro RO, Barrière F. Electrochemical properties of pH-dependent flavocytochrome c3 from Shewanella putrefaciens adsorbed onto unmodified and catechol-modified edge plane pyrolytic graphite electrode. J Electroanal Chem (Lausanne) 2019. [DOI: 10.1016/j.jelechem.2019.113232] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
|
7
|
Tian T, Fan X, Feng M, Su L, Zhang W, Chi H, Fu D. Flavin-mediated extracellular electron transfer in Gram-positive bacteria Bacillus cereus DIF1 and Rhodococcus ruber DIF2. RSC Adv 2019; 9:40903-40909. [PMID: 35540069 PMCID: PMC9076428 DOI: 10.1039/c9ra08045g] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2019] [Accepted: 11/19/2019] [Indexed: 12/11/2022] Open
Abstract
A flavin-mediated EET process was reported here in two new isolated electrochemically active Gram-positive bacterial strains DIF1 and DIF2.
Collapse
Affiliation(s)
- Tian Tian
- State Key Laboratory of Bioelectronics
- School of Biomedical Science and Engineering
- Southeast University
- Nanjing
- China
| | - Xiaoyang Fan
- State Key Laboratory of Bioelectronics
- School of Biomedical Science and Engineering
- Southeast University
- Nanjing
- China
| | - Man Feng
- State Key Laboratory of Palaeobiology and Stratigraphy
- Nanjing Institute of Geology & Palaeontology, CAS
- China
| | - Lin Su
- State Key Laboratory of Bioelectronics
- School of Biomedical Science and Engineering
- Southeast University
- Nanjing
- China
| | - Wen Zhang
- State Key Laboratory of Bioelectronics
- School of Biomedical Science and Engineering
- Southeast University
- Nanjing
- China
| | - Huimei Chi
- State Key Laboratory of Bioelectronics
- School of Biomedical Science and Engineering
- Southeast University
- Nanjing
- China
| | - Degang Fu
- State Key Laboratory of Bioelectronics
- School of Biomedical Science and Engineering
- Southeast University
- Nanjing
- China
| |
Collapse
|
8
|
Khan FST, Kumar A, Lai D, Rath SP. Ethene-bridged diiron porphyrin dimer as models of diheme cytochrome c: Structure-function correlation and modulation of heme redox potential. Inorganica Chim Acta 2019. [DOI: 10.1016/j.ica.2018.09.047] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
|
9
|
van Wonderen JH, Li D, Piper SEH, Lau CY, Jenner LP, Hall CR, Clarke TA, Watmough NJ, Butt JN. Photosensitised Multiheme Cytochromes as Light-Driven Molecular Wires and Resistors. Chembiochem 2018; 19:2206-2215. [DOI: 10.1002/cbic.201800313] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2018] [Indexed: 01/12/2023]
Affiliation(s)
- Jessica H. van Wonderen
- School of Chemistry and School of Biology; University of East Anglia; Norwich Research Park Norfolk NR4 7TJ UK
| | - Daobo Li
- School of Chemistry and School of Biology; University of East Anglia; Norwich Research Park Norfolk NR4 7TJ UK
- Present address: Department of Chemistry; University of Science and Technology of China; Hefei 230026 China
- Present address: Collaborative Innovation Center of Suzhou Nano Science and Technology; Suzhou 215123 China
| | - Samuel E. H. Piper
- School of Chemistry and School of Biology; University of East Anglia; Norwich Research Park Norfolk NR4 7TJ UK
| | - Cheuk Y. Lau
- School of Chemistry and School of Biology; University of East Anglia; Norwich Research Park Norfolk NR4 7TJ UK
| | - Leon P. Jenner
- School of Chemistry and School of Biology; University of East Anglia; Norwich Research Park Norfolk NR4 7TJ UK
| | - Christopher R. Hall
- School of Chemistry and School of Biology; University of East Anglia; Norwich Research Park Norfolk NR4 7TJ UK
- Present address: ARC Centre of Excellence in Exciton Science; School of Chemistry; The University of Melbourne; Parkville Victoria 3010 Australia
| | - Thomas A. Clarke
- School of Chemistry and School of Biology; University of East Anglia; Norwich Research Park Norfolk NR4 7TJ UK
| | - Nicholas J. Watmough
- School of Chemistry and School of Biology; University of East Anglia; Norwich Research Park Norfolk NR4 7TJ UK
| | - Julea N. Butt
- School of Chemistry and School of Biology; University of East Anglia; Norwich Research Park Norfolk NR4 7TJ UK
| |
Collapse
|
10
|
Khan FST, Banerjee S, Kumar D, Rath SP. Diheme Cytochrome c: Structure–Function Correlation and Effect of Heme−Heme Interactions. Inorg Chem 2018; 57:11498-11510. [DOI: 10.1021/acs.inorgchem.8b01368] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
| | - Sayantani Banerjee
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur-208016, India
| | - Devesh Kumar
- Department of Physics, School for Physical and Decision Sciences, Babasaheb Bhimrao Ambedkar University, Lucknow-226025, India
| | - Sankar Prasad Rath
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur-208016, India
| |
Collapse
|
11
|
Novak D, Mojovic M, Pavicevic A, Zatloukalova M, Hernychova L, Bartosik M, Vacek J. Electrochemistry and electron paramagnetic resonance spectroscopy of cytochrome c and its heme-disrupted analogs. Bioelectrochemistry 2018; 119:136-141. [DOI: 10.1016/j.bioelechem.2017.09.011] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2017] [Revised: 09/19/2017] [Accepted: 09/19/2017] [Indexed: 11/30/2022]
|
12
|
Lai D, Khan FST, Rath SP. Multiheme proteins: effect of heme–heme interactions. Dalton Trans 2018; 47:14388-14401. [DOI: 10.1039/c8dt00518d] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
This Frontier illustrates a brief personal account on the effect of heme–heme interactions in dihemes which thereby discloses some of the evolutionary design principles involved in multiheme proteins for their diverse structures and functions.
Collapse
Affiliation(s)
- Dipti Lai
- Department of Chemistry
- Indian Institute of Technology Kanpur
- Kanpur-208016
- India
| | | | - Sankar Prasad Rath
- Department of Chemistry
- Indian Institute of Technology Kanpur
- Kanpur-208016
- India
| |
Collapse
|
13
|
Modulation of the reactivity of multiheme cytochromes by site-directed mutagenesis: moving towards the optimization of microbial electrochemical technologies. J Biol Inorg Chem 2016; 22:87-97. [DOI: 10.1007/s00775-016-1409-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2016] [Accepted: 10/21/2016] [Indexed: 01/06/2023]
|
14
|
Santos TC, Silva MA, Morgado L, Dantas JM, Salgueiro CA. Diving into the redox properties of Geobacter sulfurreducens cytochromes: a model for extracellular electron transfer. Dalton Trans 2016; 44:9335-44. [PMID: 25906375 DOI: 10.1039/c5dt00556f] [Citation(s) in RCA: 85] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Geobacter bacteria have a remarkable respiratory versatility that includes the dissimilatory reduction of insoluble metal oxides in natural habitats and electron transfer to electrode surfaces from which electricity can be harvested. In both cases, electrons need to be exported from the cell interior to the exterior via a mechanism designated as extracellular electron transfer (EET). Several c-type cytochromes from G. sulfurreducens (Gs) were identified as key players in this process. Biochemical and biophysical data have been obtained for ten Gs cytochromes, including inner-membrane associated (MacA), periplasmic (PpcA, PpcB, PpcC, PpcD, PpcE and GSU1996) and outer membrane-associated (OmcF, OmcS and OmcZ). The redox properties of these cytochromes have been determined, except for PpcC and GSU1996. In this perspective, the reduction potentials of these two cytochromes were determined by potentiometric redox titrations followed by visible spectroscopy. The data obtained are taken together with those available for other key cytochromes to present a thorough overview of the current knowledge of Gs EET mechanisms and provide a possible rationalization for the existence of several multiheme cytochromes involved in the same respiratory pathways.
Collapse
Affiliation(s)
- Telma C Santos
- UCIBIO, REQUIMTE, Departamento de Química, Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa, 2829-516 Caparica, Portugal.
| | | | | | | | | |
Collapse
|
15
|
Unraveling the electron transfer processes of a nanowire protein from Geobacter sulfurreducens. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2016; 1857:7-13. [DOI: 10.1016/j.bbabio.2015.09.010] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/10/2015] [Revised: 09/04/2015] [Accepted: 09/30/2015] [Indexed: 11/19/2022]
|
16
|
Burger EM, Andrade SLA, Einsle O. Active sites without restraints: high-resolution analysis of metal cofactors. Curr Opin Struct Biol 2015; 35:32-40. [DOI: 10.1016/j.sbi.2015.07.016] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2015] [Revised: 07/24/2015] [Accepted: 07/31/2015] [Indexed: 11/29/2022]
|
17
|
Tikhonova TV, Popov VO. Structural and functional studies of multiheme cytochromes c involved in extracellular electron transport in bacterial dissimilatory metal reduction. BIOCHEMISTRY (MOSCOW) 2015; 79:1584-601. [DOI: 10.1134/s0006297914130094] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
|
18
|
Sil D, Rath SP. An ethane-bridged porphyrin dimer as a model of di-heme proteins: inorganic and bioinorganic perspectives and consequences of heme–heme interactions. Dalton Trans 2015; 44:16195-211. [DOI: 10.1039/c5dt00947b] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
A brief account of our recent efforts on how inter-heme interactions can possibly change the structure and functional properties of the individual heme centers in a highly flexible ethane-bridged porphyrin dimer has been presented.
Collapse
Affiliation(s)
- Debangsu Sil
- Department of Chemistry
- Indian Institute of Technology Kanpur
- Kanpur 208016
- India
| | - Sankar Prasad Rath
- Department of Chemistry
- Indian Institute of Technology Kanpur
- Kanpur 208016
- India
| |
Collapse
|
19
|
Sil D, Khan FST, Rath SP. Axial Thiophenolate Coordination on Diiron(III)bisporphyrin: Influence of Heme–Heme Interactions on Structure, Function and Electrochemical Properties of the Individual Heme Center. Inorg Chem 2014; 53:11925-36. [DOI: 10.1021/ic5011677] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Debangsu Sil
- Department of Chemistry, Indian Institute of Technology Kanpur
, Kanpur-208016, India
| | | | - Sankar Prasad Rath
- Department of Chemistry, Indian Institute of Technology Kanpur
, Kanpur-208016, India
| |
Collapse
|
20
|
Lillo V, Galán-Mascarós JR. Transition metal complexes with oligopeptides: single crystals and crystal structures. Dalton Trans 2014; 43:9821-33. [PMID: 24874062 DOI: 10.1039/c4dt00650j] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
The coordination chemistry of short chain peptides with transition metals is described in terms of the available crystal structures. Despite their high interest as synthetic models for metalloproteins and as building blocks for molecular materials based on the tuneable properties of oligopeptides, single crystal X-ray diffraction studies are scarce. A perusal of the most relevant results in this field allows us to define the main characteristics of oligopeptide-metal interactions, the fundamental problems for the crystallization of these complexes, and some hints to identify future promising approaches to advance the development of metallopeptide chemistry.
Collapse
Affiliation(s)
- Vanesa Lillo
- Institute of Chemical Research of Catalonia (ICIQ), Av. Països Catalans, 16. E-43007, Tarragona, Spain.
| | | |
Collapse
|
21
|
Daidone I, Paltrinieri L, Amadei A, Battistuzzi G, Sola M, Borsari M, Bortolotti CA. Unambiguous Assignment of Reduction Potentials in Diheme Cytochromes. J Phys Chem B 2014; 118:7554-7560. [DOI: 10.1021/jp506017a] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Affiliation(s)
- Isabella Daidone
- Department
of Physical and Chemical Sciences, University of L’Aquila, via
Vetoio (Coppito 1), 67010 L’Aquila, Italy
| | - Licia Paltrinieri
- Department
of Chemical and Geological Sciences, University of Modena and Reggio Emilia, via Campi 183, 41125 Modena, Italy
| | - Andrea Amadei
- Department
of Chemical Sciences and Technologies, University of Rome “Tor Vergata”, via della Ricerca Scientifica 1, 00133 Rome, Italy
| | - Gianantonio Battistuzzi
- Department
of Chemical and Geological Sciences, University of Modena and Reggio Emilia, via Campi 183, 41125 Modena, Italy
| | - Marco Sola
- Department
of Life Sciences, University of Modena and Reggio Emilia, via Campi
183, 41125 Modena, Italy
- CNR-Nano Institute
of Nanoscience, via Campi 213/A, 41125 Modena, Italy
| | - Marco Borsari
- Department
of Chemical and Geological Sciences, University of Modena and Reggio Emilia, via Campi 183, 41125 Modena, Italy
| | - Carlo Augusto Bortolotti
- Department
of Life Sciences, University of Modena and Reggio Emilia, via Campi
183, 41125 Modena, Italy
- CNR-Nano Institute
of Nanoscience, via Campi 213/A, 41125 Modena, Italy
| |
Collapse
|
22
|
Paquete CM, Louro RO. Unveiling the details of electron transfer in multicenter redox proteins. Acc Chem Res 2014; 47:56-65. [PMID: 23984680 DOI: 10.1021/ar4000696] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Metalloproteins modulate the intrinsic properties of transition metals to achieve controlled catalysis, electron transfer, or structural stabilization. Those performing electron transport, redox proteins, are a diverse class of proteins with central roles in numerous metabolic and signaling pathways, including respiration and photosynthesis. Many redox proteins have applications in industry, especially biotechnology, making them the focus of intense research. Redox proteins may contain one or multiple redox centers of the same or a different type. The complexity of proteins with multiple redox centers makes it difficult to establish a detailed molecular mechanism for their activity. Thermodynamic and kinetic information can be interpreted using the molecular structure to elucidate the protein's functional mechanism. This Account reviews experimental strategies developed in recent years to determine the detailed thermodynamic properties of multicenter redox proteins and their kinetic properties during interactions with redox partners. These strategies allow the discrimination of thermodynamic and kinetic properties of each individual redox center. The thermodynamic characterization of the redox transitions results from the combined analysis of data from NMR and UV-visible spectroscopy. Meanwhile, the kinetic characterization of intermolecular electron transfer comes from stopped-flow spectrophotometry. We illustrate an application of these strategies to a particular redox protein, the small tetraheme cytochrome from the periplasmic space of Shewanella oneidensis MR-1. This protein is a convenient prototype for developing methods for the detailed analysis of multicenter electron transfer proteins because hemes have strong UV-visible absorption bands and because heme resonances have exquisite discrimination in NMR spectra. Nonetheless, the methods are fully generalizable. Ultimately, this Account highlights the relevance of detailed characterization of the thermodynamic and kinetic properties of redox proteins. These properties are responsible for the directionality and specificity of the electron transfer process in bioenergetic pathways; a more thorough characterization of these properties should allow better-designed proteins for industrial applications.
Collapse
Affiliation(s)
- Catarina M. Paquete
- Instituto de Tecnologia Química e Biológica, Universidade Nova de Lisboa, Av. da República (EAN), 2780-157 Oeiras, Portugal
| | - Ricardo O. Louro
- Instituto de Tecnologia Química e Biológica, Universidade Nova de Lisboa, Av. da República (EAN), 2780-157 Oeiras, Portugal
| |
Collapse
|
23
|
The quest to achieve the detailed structural and functional characterization of CymA. Biochem Soc Trans 2012; 40:1291-4. [PMID: 23176470 DOI: 10.1042/bst20120114] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Shewanella oneidensis MR-1 is a sediment organism capable of dissimilatory reduction of insoluble metal compounds such as those of Fe(II) and Mn(IV). This bacterium has been used as a model organism for potential applications in bioremediation of contaminated environments and in the production of energy in microbial fuel cells. The capacity of Shewanella to perform extracellular reduction of metals is linked to the action of several multihaem cytochromes that may be periplasmic or can be associated with the inner or outer membrane. One of these cytochromes is CymA, a membrane-bound tetrahaem cytochrome localized in the periplasm that mediates the electron transfer between the quinone pool in the cytoplasmic membrane and several periplasmic proteins. Although CymA has the capacity to regulate multiple anaerobic respiratory pathways, little is known about the structure and functional mechanisms of this focal protein. Understanding the structure and function of membrane proteins is hampered by inherent difficulties associated with their purification since the choice of the detergents play a critical role in the protein structure and stability. In the present mini-review, we detail the current state of the art in the characterization of CymA, and add recent information on haem structural behaviour for CymA solubilized in different detergents. These structural differences are deduced from NMR spectroscopy data that provide information on the geometry of the haem axial ligands. At least two different conformational forms of CymA are observed for different detergents, which seem to be related to the micelle size. These results provide guidance for the discovery of the most promising detergent that mimics the native lipid bilayer and is compatible with biochemical and structural studies.
Collapse
|
24
|
Patra R, Sahoo D, Dey S, Sil D, Rath SP. Switching Orientation of Two Axial Imidazole Ligands between Parallel and Perpendicular in Low-Spin Fe(III) and Fe(II) Nonplanar Porphyrinates. Inorg Chem 2012; 51:11294-305. [DOI: 10.1021/ic300229u] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Ranjan Patra
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur-208016, India
| | - Dipankar Sahoo
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur-208016, India
| | - Soumyajit Dey
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur-208016, India
| | - Debangsu Sil
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur-208016, India
| | - Sankar Prasad Rath
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur-208016, India
| |
Collapse
|
25
|
Geothrix fermentans secretes two different redox-active compounds to utilize electron acceptors across a wide range of redox potentials. Appl Environ Microbiol 2012; 78:6987-95. [PMID: 22843516 DOI: 10.1128/aem.01460-12] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
The current understanding of dissimilatory metal reduction is based primarily on isolates from the proteobacterial genera Geobacter and Shewanella. However, environments undergoing active Fe(III) reduction often harbor less-well-studied phyla that are equally abundant. In this work, electrochemical techniques were used to analyze respiratory electron transfer by the only known Fe(III)-reducing representative of the Acidobacteria, Geothrix fermentans. In contrast to previously characterized metal-reducing bacteria, which typically reach maximal rates of respiration at electron acceptor potentials of 0 V versus standard hydrogen electrode (SHE), G. fermentans required potentials as high as 0.55 V to respire at its maximum rate. In addition, G. fermentans secreted two different soluble redox-active electron shuttles with separate redox potentials (-0.2 V and 0.3 V). The compound with the lower midpoint potential, responsible for 20 to 30% of electron transfer activity, was riboflavin. The behavior of the higher-potential compound was consistent with hydrophilic UV-fluorescent molecules previously found in G. fermentans supernatants. Both electron shuttles were also produced when cultures were grown with Fe(III), but not when fumarate was the electron acceptor. This study reveals that Geothrix is able to take advantage of higher-redox-potential environments, demonstrates that secretion of flavin-based shuttles is not confined to Shewanella, and points to the existence of high-potential-redox-active compounds involved in extracellular electron transfer. Based on differences between the respiratory strategies of Geothrix and Geobacter, these two groups of bacteria could exist in distinctive environmental niches defined by redox potential.
Collapse
|
26
|
Fonseca BM, Tien M, Rivera M, Shi L, Louro RO. Efficient and selective isotopic labeling of hemes to facilitate the study of multiheme proteins. Biotechniques 2012; 52:000113859. [PMID: 26307249 DOI: 10.2144/000113859] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2012] [Accepted: 04/02/2012] [Indexed: 11/23/2022] Open
Abstract
Specific isotopic labeling of hemes provides a unique opportunity to characterize the structure and function of heme-proteins. Unfortunately, current methods do not allow efficient labeling in high yields of multiheme cytochromes c, which are of great biotechnological interest. Here, a method for production of recombinant multiheme cytochromes c in Escherichia coli with isotopically labeled hemes is reported. A small tetraheme cytochrome of 12 kDa from Shewanella oneidensis MR-1 was used to demonstrate the method, achieving a production of 4 mg pure protein per liter. This method achieves, in a single step, efficient expression and incorporation of hemes isotopically labeled in specific atom positions adequate for spectroscopic characterization of these complex heme proteins. It is, furthermore, of general application to heme proteins, opening new possibilities for the characterization of this important class of proteins.
Collapse
Affiliation(s)
- Bruno M Fonseca
- Instituto de Tecnologia Química e Biológica, Universidade Nova de Lisboa, Oeiras, Portugal
| | - Ming Tien
- Department of Biochemistry and Molecular Biology, Pennsylvania State University, University Park, PA, USA
| | - Mario Rivera
- Department of Chemistry, University of Kansas, Lawrence, KS, USA
| | - Liang Shi
- Microbiology Group, Pacific Northwest National Laboratory, Richland, WA, USA
| | - Ricardo O Louro
- Instituto de Tecnologia Química e Biológica, Universidade Nova de Lisboa, Oeiras, Portugal
| |
Collapse
|
27
|
Arends JBA, Verstraete W. 100 years of microbial electricity production: three concepts for the future. Microb Biotechnol 2011; 5:333-46. [PMID: 21958308 PMCID: PMC3821677 DOI: 10.1111/j.1751-7915.2011.00302.x] [Citation(s) in RCA: 100] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
Bioelectrochemical systems (BES) have been explored according to three main concepts: to produce energy from organic substrates, to generate products and to provide specific environmental services. In this work, by using an engineering approach, biological conversion rates are calculated for BES resp. anaerobic digestion. These rates are compared with currents produced by chemical batteries and chemical fuel cells in order to position BES in the 'energy'-market. To evaluate the potential of generating various products, the biochemistry behind the biological conversion rates is examined in relation to terminal electron transfer molecules. By comparing kinetics rather than thermodynamics, more insight is gained in the biological bottlenecks that hamper a BES. The short-term future for BES research and its possible application is situated in smart niches in sustainable environmental development, i.e. in processes where no large currents or investment cost intensive reactors are needed to obtain the desired results. Some specific examples are identified.
Collapse
|
28
|
Fonseca BM, Paquete CM, Salgueiro CA, Louro RO. The role of intramolecular interactions in the functional control of multiheme cytochromes c. FEBS Lett 2011; 586:504-9. [PMID: 21856299 DOI: 10.1016/j.febslet.2011.08.019] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2011] [Accepted: 08/09/2011] [Indexed: 10/17/2022]
Abstract
Detailed thermodynamic and structural data measured in soluble monomeric multiheme cytochromes c provided the basis to investigate the functional significance of interactions between redox co-factors. The steep decay of intramolecular interactions with distance means that close proximity of the redox centers is necessary to modulate the intrinsic reduction potentials in a significant way. This ensures selection of specific populations during redox activity in addition to maintaining fast intramolecular electron transfer. Therefore, intramolecular interactions between redox co-factors play an important role in establishing the biological function of the protein by controlling how electrons flow through and are distributed among the co-factors.
Collapse
Affiliation(s)
- Bruno M Fonseca
- Instituto de Tecnologia Química e Biológica, Universidade Nova de Lisboa, Av. da República, EAN, 2780-157 Oeiras, Portugal
| | | | | | | |
Collapse
|
29
|
Qian Y, Paquete CM, Louro RO, Ross DE, Labelle E, Bond DR, Tien M. Mapping the iron binding site(s) on the small tetraheme cytochrome of Shewanella oneidensis MR-1. Biochemistry 2011; 50:6217-24. [PMID: 21682327 DOI: 10.1021/bi2005015] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
In the model microbe Shewanella oneidensis, multi-heme proteins are utilized for respiratory metabolism where metals serve as the terminal electron acceptor. Among those is the periplasm-localized small tetraheme cytochrome (STC). STC has been extensively characterized structurally and electrochemically to which electron flow in and out of the protein has been modeled. However, until the present work, no kinetic studies have been performed to probe the route of electron flow or to determine the iron-binding site on STC. Using iron chelated by EDTA, NTA, or citrate, we have used chemical modification, site-directed mutagenesis along with isothermal titration calorimetry (ITC), and stopped-flow measurements to identify the iron binding site of STC. Chemical modifications of STC revealed that carboxyl groups on STC are involved in binding of EDTA-Fe(3+). Scanning mutagenesis was performed on Asp and Glu to probe the putative iron-binding site on STC. Two STC mutants (D21N; D80N) showed ∼70% decrease in observed electron transfer rate constant with EDTA-Fe(3+) from transient-state kinetic measurements. The impaired reactivity of STC (D80N/D21N) with EDTA-Fe(3+) was further confirmed by a significant decrease (>10-fold) in iron binding affinity.
Collapse
Affiliation(s)
- Yufeng Qian
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, Pennsylvania 16802, United States
| | | | | | | | | | | | | |
Collapse
|
30
|
Pound GJ, Pletnev AA, Fang X, Pletneva EV. A small fluorophore reporter of protein conformation and redox state. Chem Commun (Camb) 2011; 47:5714-6. [PMID: 21487611 DOI: 10.1039/c1cc10896d] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A new thiol-specific reagent introduces a small bis(methylamino)terephthalic acid fluorophore into proteins. The noninvasive probe with distinct spectroscopic properties offers many advantages for protein labeling, purification, and mechanistic work promising to serve as a powerful tool in studies of protein folding and heme redox reactions.
Collapse
Affiliation(s)
- Graham J Pound
- Department of Chemistry, Dartmouth College, Hanover, NH 03755, USA
| | | | | | | |
Collapse
|
31
|
Quinlan A, Murat D, Vali H, Komeili A. The HtrA/DegP family protease MamE is a bifunctional protein with roles in magnetosome protein localization and magnetite biomineralization. Mol Microbiol 2011; 80:1075-87. [PMID: 21414040 DOI: 10.1111/j.1365-2958.2011.07631.x] [Citation(s) in RCA: 70] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Magnetotactic bacteria contain nanometre-sized, membrane-bound organelles, called magnetosomes, which are tasked with the biomineralization of small crystals of the iron oxide magnetite allowing the organism to use geomagnetic field lines for navigation. A key player in this process is the HtrA/DegP family protease MamE. In its absence, Magnetospirillum magneticum str AMB-1 is able to form magnetosome membranes but not magnetite crystals, a defect previously linked to the mislocalization of magnetosome proteins. In this work we use a directed genetic approach to find that MamE, and another predicted magnetosome-associated protease, MamO, likely function as proteases in vivo. However, as opposed to the complete loss of mamE where no biomineralization is observed, the protease-deficient variant of this protein still supports the initiation and formation of small, 20 nm-sized crystals of magnetite, too small to hold a permanent magnetic dipole moment. This analysis also reveals that MamE is a bifunctional protein with a protease-independent role in magnetosome protein localization and a protease-dependent role in maturation of small magnetite crystals. Together, these results imply the existence of a previously unrecognized 'checkpoint' in biomineralization where MamE moderates the completion of magnetite formation and thus committal to magneto-aerotaxis as the organism's dominant mode of navigating the environment.
Collapse
Affiliation(s)
- Anna Quinlan
- Department of Molecular and Cell Biology, University of California Berkeley, 111 Koshland Hall, Berkeley, CA 94720, USA
| | | | | | | |
Collapse
|
32
|
Alves AS, Paquete CM, Fonseca BM, Louro RO. Exploration of the ‘cytochromome’ of Desulfuromonas acetoxidans, a marine bacterium capable of powering microbial fuel cells. Metallomics 2011; 3:349-53. [DOI: 10.1039/c0mt00084a] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
|