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Liu S, Chen Y, Du T, Zhao W, Liu X, Zhang H, Yuan Q, Gao L, Dong Y, Gao X, Gong Y, Cao P. A dimer-monomer transition captured by the crystal structures of cyanobacterial apo flavodoxin. Biochem Biophys Res Commun 2023; 639:134-141. [PMID: 36493556 DOI: 10.1016/j.bbrc.2022.11.089] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2022] [Accepted: 11/27/2022] [Indexed: 11/30/2022]
Abstract
In cyanobacteria and algae (but not plants), flavodoxin (Fld) replaces ferredoxin (Fd) under stress conditions to transfer electrons from photosystem I (PSI) to ferredoxin-NADP+ reductase (FNR) during photosynthesis. Fld constitutes a small electron carrier noncovalently bound to flavin mononucleotide (FMN), and also an ideal model for revealing the protein/flavin-binding mechanism because of its relative simplicity compared to other flavoproteins. Here, we report two crystal structures of apo-Fld from Synechococcus sp. PCC 7942, one dimeric structure of 2.09 Å and one monomeric structure of 1.84 Å resolution. Analytical ultracentrifugation showed that in solution, apo-Fld exists both as monomers and dimers. Our dimer structure contains two ligand-binding pockets separated by a distance of 45 Å, much longer than the previous structures of FMN-bound dimers. These results suggested a potential dimer-monomer transition mechanism of cyanobacterial apo-Fld. We further propose that the dimer represents the "standby" state to stabilize itself, while the monomer constitutes the "ready" state to bind FMN. Furthermore, we generated a new docking model of cyanobacterial Fld-FNR complex based on the recently reported cryo-EM structures, and mapped the special interactions between Fld and FNR in detail.
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Affiliation(s)
- Shuwen Liu
- Faculty of Environment and Life, Beijing University of Technology, 100 Pingleyuan, Chaoyang District, Beijing, 100124, China
| | - Yuanyuan Chen
- The Research Platform for Protein Sciences, Institute of Biophysics, Chinese Academy of Sciences, 15 Datun Road, Chaoyang District, Beijing, 100101, China
| | - Tianming Du
- Faculty of Environment and Life, Beijing University of Technology, 100 Pingleyuan, Chaoyang District, Beijing, 100124, China
| | - Wencong Zhao
- Faculty of Environment and Life, Beijing University of Technology, 100 Pingleyuan, Chaoyang District, Beijing, 100124, China
| | - Xuejing Liu
- Faculty of Environment and Life, Beijing University of Technology, 100 Pingleyuan, Chaoyang District, Beijing, 100124, China
| | - Heng Zhang
- Center for Multidisciplinary Research, Institute of High Energy Physics, Chinese Academy of Sciences, 19B YuquanLu, Shijingshan District, Beijing, 100049, China
| | - Qing Yuan
- Faculty of Environment and Life, Beijing University of Technology, 100 Pingleyuan, Chaoyang District, Beijing, 100124, China
| | - Liang Gao
- Faculty of Environment and Life, Beijing University of Technology, 100 Pingleyuan, Chaoyang District, Beijing, 100124, China
| | - Yuhui Dong
- Center for Multidisciplinary Research, Institute of High Energy Physics, Chinese Academy of Sciences, 19B YuquanLu, Shijingshan District, Beijing, 100049, China
| | - Xueyun Gao
- Faculty of Environment and Life, Beijing University of Technology, 100 Pingleyuan, Chaoyang District, Beijing, 100124, China.
| | - Yong Gong
- Center for Multidisciplinary Research, Institute of High Energy Physics, Chinese Academy of Sciences, 19B YuquanLu, Shijingshan District, Beijing, 100049, China.
| | - Peng Cao
- Faculty of Environment and Life, Beijing University of Technology, 100 Pingleyuan, Chaoyang District, Beijing, 100124, China.
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2
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Lewis CM, Flory JD, Moore TA, Moore AL, Rittmann BE, Vermaas WFJ, Torres CI, Fromme P. Electrochemically Driven Photosynthetic Electron Transport in Cyanobacteria Lacking Photosystem II. J Am Chem Soc 2022; 144:2933-2942. [PMID: 35157427 DOI: 10.1021/jacs.1c09291] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Light-activated photosystem II (PSII) carries out the critical step of splitting water in photosynthesis. However, PSII is susceptible to light-induced damage. Here, results are presented from a novel microbial electro-photosynthetic system (MEPS) that uses redox mediators in conjunction with an electrode to drive electron transport in live Synechocystis (ΔpsbB) cells lacking PSII. MEPS-generated, light-dependent current increased with light intensity up to 2050 μmol photons m-2 s-1, which yielded a delivery rate of 113 μmol electrons h-1 mg-chl-1 and an average current density of 150 A m-2 s-1 mg-chl-1. P700+ re-reduction kinetics demonstrated that initial rates exceeded wildtype PSII-driven electron delivery. The electron delivery occurs ahead of the cytochrome b6f complex to enable both NADPH and ATP production. This work demonstrates an electrochemical system that can drive photosynthetic electron transport, provides a platform for photosynthetic foundational studies, and has the potential for improving photosynthetic performance at high light intensities.
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Affiliation(s)
- Christine M Lewis
- School of Molecular Sciences, Arizona State University, Tempe, Arizona 85287, United States.,Biodesign Institute Center for Applied Structural Discovery, Arizona State University, Tempe, Arizona 85287, United States.,Biodesign Institute Swette Center for Environmental Biotechnology, Arizona State University, Tempe, Arizona 85287, United States
| | - Justin D Flory
- Biodesign Institute Center for Applied Structural Discovery, Arizona State University, Tempe, Arizona 85287, United States.,Engineering Center for Negative Carbon Emmisions, at Arizona State University, Tempe, Arizona 85281, United States
| | - Thomas A Moore
- School of Molecular Sciences, Arizona State University, Tempe, Arizona 85287, United States.,Julie Ann Wrigley Global Institute of Sustainability and Innovation, Arizona State University, Tempe Arizona 85287, United States
| | - Ana L Moore
- School of Molecular Sciences, Arizona State University, Tempe, Arizona 85287, United States.,Julie Ann Wrigley Global Institute of Sustainability and Innovation, Arizona State University, Tempe Arizona 85287, United States
| | - Bruce E Rittmann
- School of Sustainable Engineering and the Built Environment, Arizona State University, Tempe, Arizona 85287, United States.,Biodesign Institute Swette Center for Environmental Biotechnology, Arizona State University, Tempe, Arizona 85287, United States
| | - Wim F J Vermaas
- School of Life Sciences, Arizona State University, Tempe, Arizona 85287, United States
| | - César I Torres
- Biodesign Institute Swette Center for Environmental Biotechnology, Arizona State University, Tempe, Arizona 85287, United States.,School for Engineering of Matter, Transport and Energy, Arizona State University, Tempe, Arizona 85287, United States
| | - Petra Fromme
- School of Molecular Sciences, Arizona State University, Tempe, Arizona 85287, United States.,Biodesign Institute Center for Applied Structural Discovery, Arizona State University, Tempe, Arizona 85287, United States
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3
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Adams EM, Lampret O, König B, Happe T, Havenith M. Solvent dynamics play a decisive role in the complex formation of biologically relevant redox proteins. Phys Chem Chem Phys 2020; 22:7451-7459. [PMID: 32215444 DOI: 10.1039/d0cp00267d] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Electron transfer processes between proteins are vital in many biological systems. Yet, the role of the solvent in influencing these redox reactions remains largely unknown. In this study, terahertz-time domain spectroscopy (THz-TDS) is used to probe the collective hydration dynamics of flavoenzyme ferredoxin-NADP+-reductase (FNR), electron transfer protein ferredoxin-1 (PetF), and the transient complex that results from their interaction. Results reveal changes in the sub-picosecond hydration dynamics that are dependent upon the surface electrostatic properties of the individual proteins and the transient complex. Retarded solvent dynamics of 8-9 ps are observed for FNR, PetF, and the FNR:PetF transient complex. Binding of the FNR:PetF complex to the substrate NADP+ results in bulk-like solvent dynamics of 7 ps, showing that formation of the ternary complex is entropically favored. Our THz measurements reveal that the electrostatic interaction of the protein surface with water results in charge sensitive changes in the solvent dynamics. Complex formation between the positively charged FNR:NADP+ pre-complex and the negatively charged PetF is not only entropically favored, but in addition the solvent reorganization into more bulk-like water assists the molecular recognition process. The change in hydration dynamics observed here suggests that the interaction with the solvent plays a significant role in mediating electron transfer processes between proteins.
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Affiliation(s)
- Ellen M Adams
- Lehrstuhl für Physkalische Chemie II, Ruhr Universität Bochum, 44801 Bochum, Germany.
| | - Oliver Lampret
- AG Photobiotechnologie, Ruhr Universität Bochum, 44801 Bochum, Germany
| | - Benedikt König
- Lehrstuhl für Physkalische Chemie II, Ruhr Universität Bochum, 44801 Bochum, Germany.
| | - Thomas Happe
- AG Photobiotechnologie, Ruhr Universität Bochum, 44801 Bochum, Germany
| | - Martina Havenith
- Lehrstuhl für Physkalische Chemie II, Ruhr Universität Bochum, 44801 Bochum, Germany.
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Wolfe KD, Dervishogullari D, Stachurski CD, Passantino JM, Kane Jennings G, Cliffel DE. Photosystem I Multilayers within Porous Indium Tin Oxide Cathodes Enhance Mediated Electron Transfer. ChemElectroChem 2019. [DOI: 10.1002/celc.201901628] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Affiliation(s)
- Kody D. Wolfe
- Interdisciplinary Materials Science Program Vanderbilt University Nashville Tennessee 37235-1822 United States
| | - Dilek Dervishogullari
- Department of Chemistry Vanderbilt University Nashville Tennessee 37235-1822 United States
| | | | - Joshua M. Passantino
- Department of Chemical and Biomolecular Engineering Vanderbilt University Nashville Tennessee 37235-1822 United States
| | - G. Kane Jennings
- Department of Chemical and Biomolecular Engineering Vanderbilt University Nashville Tennessee 37235-1822 United States
| | - David E. Cliffel
- Department of Chemistry Vanderbilt University Nashville Tennessee 37235-1822 United States
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5
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Vorphal MA, Bruna C, Wandersleben T, Dagnino-Leone J, Lobos-González F, Uribe E, Martínez-Oyanedel J, Bunster M. Molecular and functional characterization of ferredoxin NADP(H) oxidoreductase from Gracilaria chilensis and its complex with ferredoxin. Biol Res 2017; 50:39. [PMID: 29221464 PMCID: PMC5723097 DOI: 10.1186/s40659-017-0144-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2017] [Accepted: 11/04/2017] [Indexed: 12/18/2022] Open
Abstract
Backgroud Ferredoxin NADP(H) oxidoreductases (EC 1.18.1.2) (FNR) are flavoenzymes present in photosynthetic organisms; they are relevant for the production of reduced donors to redox reactions, i.e. in photosynthesis, the reduction of NADP+ to NADPH using the electrons provided by Ferredoxin (Fd), a small FeS soluble protein acceptor of electrons from PSI in chloroplasts. In rhodophyta no information about this system has been reported, this work is a contribution to the molecular and functional characterization of FNR from Gracilaria chilensis, also providing a structural analysis of the complex FNR/Fd. Methods The biochemical and kinetic characterization of FNR was performed from the enzyme purified from phycobilisomes enriched fractions. The sequence of the gene that codifies for the enzyme, was obtained using primers designed by comparison with sequences of Synechocystis and EST from Gracilaria. 5′RACE was used to confirm the absence of a CpcD domain in FNRPBS of Gracilaria chilensis. A three dimensional model for FNR and Fd, was built by comparative modeling and a model for the complex FNR: Fd by docking. Results The kinetic analysis shows KMNADPH of 12.5 M and a kcat of 86 s−1, data consistent with the parameters determined for the enzyme purified from a soluble extract. The sequence for FNR was obtained and translated to a protein of 33646 Da. A FAD and a NADP+ binding domain were clearly identified by sequence analysis as well as a chloroplast signal sequence. Phycobilisome binding domain, present in some cyanobacteria was absent. Transcriptome analysis of Gch revealed the presence of two Fd; FdL and FdS , sharing the motif CX5CX2CX29X. The analysis indicated that the most probable partner for FNR is FdS. Conclusion The interaction model produced, was consistent with functional properties reported for FNR in plants leaves, and opens the possibilities for research in other rhodophyta of commercial interest. Electronic supplementary material The online version of this article (10.1186/s40659-017-0144-5) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- María Alejandra Vorphal
- Laboratorio de Biofísica Molecular, Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias Biológicas, Universidad de Concepción, Barrio Universitario S/N, Casilla 160_C, Concepción, Chile
| | - Carola Bruna
- Laboratorio de Biofísica Molecular, Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias Biológicas, Universidad de Concepción, Barrio Universitario S/N, Casilla 160_C, Concepción, Chile
| | - Traudy Wandersleben
- Laboratorio de Biofísica Molecular, Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias Biológicas, Universidad de Concepción, Barrio Universitario S/N, Casilla 160_C, Concepción, Chile
| | - Jorge Dagnino-Leone
- Laboratorio de Biofísica Molecular, Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias Biológicas, Universidad de Concepción, Barrio Universitario S/N, Casilla 160_C, Concepción, Chile
| | - Francisco Lobos-González
- Laboratorio de Biofísica Molecular, Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias Biológicas, Universidad de Concepción, Barrio Universitario S/N, Casilla 160_C, Concepción, Chile
| | - Elena Uribe
- Laboratorio de Enzimología, Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias Biológicas, Universidad de Concepción, Barrio Universitario S/N, Casilla 160_C, Concepción, Chile
| | - José Martínez-Oyanedel
- Laboratorio de Biofísica Molecular, Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias Biológicas, Universidad de Concepción, Barrio Universitario S/N, Casilla 160_C, Concepción, Chile.
| | - Marta Bunster
- Laboratorio de Biofísica Molecular, Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias Biológicas, Universidad de Concepción, Barrio Universitario S/N, Casilla 160_C, Concepción, Chile.
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6
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Mulo P, Medina M. Interaction and electron transfer between ferredoxin-NADP + oxidoreductase and its partners: structural, functional, and physiological implications. PHOTOSYNTHESIS RESEARCH 2017; 134:265-280. [PMID: 28361449 DOI: 10.1007/s11120-017-0372-0] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/27/2016] [Accepted: 03/20/2017] [Indexed: 05/25/2023]
Abstract
Ferredoxin-NADP+ reductase (FNR) catalyzes the last step of linear electron transfer in photosynthetic light reactions. The FAD cofactor of FNR accepts two electrons from two independent reduced ferredoxin molecules (Fd) in two sequential steps, first producing neutral semiquinone and then the fully anionic reduced, or hydroquinone, form of the enzyme (FNRhq). FNRhq transfers then both electrons in a single hydride transfer step to NADP+. We are presenting the recent progress in studies focusing on Fd:FNR interaction and subsequent electron transfer processes as well as on interaction of FNR with NADP+/H followed by hydride transfer, both from the structural and functional point of views. We also present the current knowledge about the physiological role(s) of various FNR isoforms present in the chloroplasts of higher plants and the functional impact of subchloroplastic location of FNR. Moreover, open questions and current challenges about the structure, function, and physiology of FNR are discussed.
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Affiliation(s)
- Paula Mulo
- Molecular Plant Biology, University of Turku, 20520, Turku, Finland
| | - Milagros Medina
- Department of Biochemistry and Molecular and Cellular Biology, Faculty of Sciences, and Institute of Biocomputation and Physics of Complex Systems (Joint Units: BIFI-IQFR and GBsC-CSIC), University of Zaragoza, 50009, Zaragoza, Spain.
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7
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Alcántara-Sánchez F, Leyva-Castillo LE, Chagolla-López A, González de la Vara L, Gómez-Lojero C. Distribution of isoforms of ferredoxin-NADP + reductase (FNR) in cyanobacteria in two growth conditions. Int J Biochem Cell Biol 2017; 85:123-134. [PMID: 28189842 DOI: 10.1016/j.biocel.2017.02.004] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2016] [Revised: 02/01/2017] [Accepted: 02/07/2017] [Indexed: 10/20/2022]
Abstract
Ferredoxin-NADP+ reductase (FNR) transfers reducing equivalents between ferredoxin and NADP(H) in the photosynthetic electron transport chains of chloroplasts and cyanobacteria. In most cyanobacteria, FNR is coded by a single petH gene. The structure of FNR in photosynthetic organisms can be constituted by FAD-binding and NADPH-binding domains (FNR-2D), or by these and an additional N-terminal domain (FNR-3D). In this article, biochemical evidence is provided supporting the induction of FNR-2D by iron or combined nitrogen deficiency in the cyanobacteria Synechocystis PCC 6803 and Anabaena variabilis ATCC 29413. In cell extracts of these cyanobacteria, most of FNR was associated to phycobilisomes (PBS) or phycocyanin (PC), and the rest was found as free enzyme. Free FNR activity increased in both cyanobacteria under iron stress and during diazotrophic conditions in A. variabilis. Characterization of FNR from both cyanobacteria showed that the PBS-associated enzyme was FNR-3D and the free enzyme was mostly a FNR-2D isoform. Predominant isoforms in heterocysts of A. variabilis were FNR-2D; where its N-terminal sequence lacked an initial (formyl)methionine. This means that FNR-3D is targeted to thylakoid membrane, and anchored to PBS, and FNR-2D is found as a soluble protein in the cytoplasm, when iron or fixed nitrogen deficiencies prevail in the environment. Moreover, given that Synechocystis and Anabaena variabilis are dissimilar in genotype, phenotype and ecology, the presence of these two-domain proteins in these species suggests that the mechanism of FNR induction is common among cyanobacteria regardless of their habitat and morphotype.
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Affiliation(s)
- Felipe Alcántara-Sánchez
- Departamento de Bioquímica, Centro de Investigación y Estudios Avanzados-IPN, Apartado Postal 14-740, 07000 Cd de México, Mexico.
| | - Lourdes Elizabeth Leyva-Castillo
- Departamento de Bioquímica, Centro de Investigación y Estudios Avanzados-IPN, Apartado Postal 14-740, 07000 Cd de México, Mexico.
| | | | | | - Carlos Gómez-Lojero
- Departamento de Bioquímica, Centro de Investigación y Estudios Avanzados-IPN, Apartado Postal 14-740, 07000 Cd de México, Mexico.
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8
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Boehm M, Alahuhta M, Mulder DW, Peden EA, Long H, Brunecky R, Lunin VV, King PW, Ghirardi ML, Dubini A. Crystal structure and biochemical characterization of Chlamydomonas FDX2 reveal two residues that, when mutated, partially confer FDX2 the redox potential and catalytic properties of FDX1. PHOTOSYNTHESIS RESEARCH 2016; 128:45-57. [PMID: 26526668 PMCID: PMC4791469 DOI: 10.1007/s11120-015-0198-6] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/26/2015] [Accepted: 10/14/2015] [Indexed: 05/25/2023]
Abstract
The green alga Chlamydomonas reinhardtii contains six plastidic [2Fe2S]-cluster ferredoxins (FDXs), with FDX1 as the predominant isoform under photoautotrophic growth. FDX2 is highly similar to FDX1 and has been shown to interact with specific enzymes (such as nitrite reductase), as well as to share interactors with FDX1, such as the hydrogenases (HYDA), ferredoxin:NAD(P) reductase I (FNR1), and pyruvate:ferredoxin oxidoreductase (PFR1), albeit performing at low catalytic rates. Here we report the FDX2 crystal structure solved at 1.18 Å resolution. Based on differences between the Chlorella fusca FDX1 and C. reinhardtii FDX2 structures, we generated and purified point-mutated versions of the FDX2 protein and assayed them in vitro for their ability to catalyze hydrogen and NADPH photo-production. The data show that structural differences at two amino acid positions contribute to functional differences between FDX1 and FDX2, suggesting that FDX2 might have evolved from FDX1 toward a different physiological role in the cell. Moreover, we demonstrate that the mutations affect both the midpoint potentials of the FDX and kinetics of the FNR reaction, possibly due to altered binding between FDX and FNR. An effect on H2 photo-production rates was also observed, although the kinetics of the reaction were not further characterized.
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Affiliation(s)
- Marko Boehm
- Biosciences Center, National Renewable Energy Laboratory, Mail Stop: 3313, 15013 Denver West Parkway, Golden, CO, 80401, USA
| | - Markus Alahuhta
- Biosciences Center, National Renewable Energy Laboratory, Mail Stop: 3313, 15013 Denver West Parkway, Golden, CO, 80401, USA
| | - David W Mulder
- Biosciences Center, National Renewable Energy Laboratory, Mail Stop: 3313, 15013 Denver West Parkway, Golden, CO, 80401, USA
| | - Erin A Peden
- Biosciences Center, National Renewable Energy Laboratory, Mail Stop: 3313, 15013 Denver West Parkway, Golden, CO, 80401, USA
| | - Hai Long
- Computational Science Center, National Renewable Energy Laboratory, 15013 Denver West Parkway, Golden, CO, 80401, USA
| | - Roman Brunecky
- Biosciences Center, National Renewable Energy Laboratory, Mail Stop: 3313, 15013 Denver West Parkway, Golden, CO, 80401, USA
| | - Vladimir V Lunin
- Biosciences Center, National Renewable Energy Laboratory, Mail Stop: 3313, 15013 Denver West Parkway, Golden, CO, 80401, USA
| | - Paul W King
- Biosciences Center, National Renewable Energy Laboratory, Mail Stop: 3313, 15013 Denver West Parkway, Golden, CO, 80401, USA
| | - Maria L Ghirardi
- Biosciences Center, National Renewable Energy Laboratory, Mail Stop: 3313, 15013 Denver West Parkway, Golden, CO, 80401, USA
| | - Alexandra Dubini
- Biosciences Center, National Renewable Energy Laboratory, Mail Stop: 3313, 15013 Denver West Parkway, Golden, CO, 80401, USA.
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Marcuello C, de Miguel R, Martínez-Júlvez M, Gómez-Moreno C, Lostao A. Mechanostability of the Single-Electron-Transfer Complexes of Anabaena Ferredoxin-NADP(+) Reductase. Chemphyschem 2015; 16:3161-9. [PMID: 26248023 DOI: 10.1002/cphc.201500534] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2015] [Indexed: 01/24/2023]
Abstract
The complexes formed between the flavoenzyme ferredoxin-NADP(+) reductase (FNR; NADP(+) =nicotinamide adenine dinucleotide phosphate) and its redox protein partners, ferredoxin (Fd) and flavodoxin (Fld), have been analysed by using dynamic force spectroscopy through AFM. A strategy is developed to immobilise proteins on a substrate and AFM tip to optimise the recognition ability. The differences in the recognition efficiency regarding a random attachment procedure, together with nanomechanical results, show two binding models for these systems. The interaction of the reductase with the natural electron donor, Fd, is threefold stronger and its lifetime is longer and more specific than that with the substitute under iron-deficient conditions, Fld. The higher bond probability and two possible dissociation pathways in Fld binding to FNR are probably due to the nature of this complex, which is closer to a dynamic ensemble model. This is in contrast with the one-step dissociation kinetics that has been observed and a specific interaction described for the FNR:Fd complex.
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Affiliation(s)
- Carlos Marcuello
- Laboratorio de Microscopías Avanzadas, Instituto de Nanociencia de Aragón, Universidad de Zaragoza, C/Mariano Esquillor, s/n. Ed. I+D+i, 50018, Zaragoza, Spain
| | - Rocío de Miguel
- Laboratorio de Microscopías Avanzadas, Instituto de Nanociencia de Aragón, Universidad de Zaragoza, C/Mariano Esquillor, s/n. Ed. I+D+i, 50018, Zaragoza, Spain
| | - Marta Martínez-Júlvez
- Departamento de Bioquímica y Biología Molecular y Celular, Universidad de Zaragoza, Facultad de Ciencias, C/Pedro Cerbuna, 12, 50009, Zaragoza, Spain
| | - Carlos Gómez-Moreno
- Laboratorio de Microscopías Avanzadas, Instituto de Nanociencia de Aragón, Universidad de Zaragoza, C/Mariano Esquillor, s/n. Ed. I+D+i, 50018, Zaragoza, Spain.,Departamento de Bioquímica y Biología Molecular y Celular, Universidad de Zaragoza, Facultad de Ciencias, C/Pedro Cerbuna, 12, 50009, Zaragoza, Spain
| | - Anabel Lostao
- Laboratorio de Microscopías Avanzadas, Instituto de Nanociencia de Aragón, Universidad de Zaragoza, C/Mariano Esquillor, s/n. Ed. I+D+i, 50018, Zaragoza, Spain. .,Fundación ARAID, C/María de Luna, 11. Ed. CEEI Aragón, 50018, Zaragoza, Spain.
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10
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A theoretical multiscale treatment of protein-protein electron transfer: The ferredoxin/ferredoxin-NADP(+) reductase and flavodoxin/ferredoxin-NADP(+) reductase systems. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2015; 1847:1530-8. [PMID: 26385068 DOI: 10.1016/j.bbabio.2015.09.002] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/17/2015] [Revised: 09/10/2015] [Accepted: 09/14/2015] [Indexed: 11/21/2022]
Abstract
In the photosynthetic electron transfer (ET) chain, two electrons transfer from photosystem I to the flavin-dependent ferredoxin-NADP(+) reductase (FNR) via two sequential independent ferredoxin (Fd) electron carriers. In some algae and cyanobacteria (as Anabaena), under low iron conditions, flavodoxin (Fld) replaces Fd as single electron carrier. Extensive mutational studies have characterized the protein-protein interaction in FNR/Fd and FNR/Fld complexes. Interestingly, even though Fd and Fld share the interaction site on FNR, individual residues on FNR do not participate to the same extent in the interaction with each of the protein partners, pointing to different electron transfer mechanisms. Despite of extensive mutational studies, only FNR/Fd X-ray structures from Anabaena and maize have been solved; structural data for FNR/Fld remains elusive. Here, we present a multiscale modelling approach including coarse-grained and all-atom protein-protein docking, the QM/MM e-Pathway analysis and electronic coupling calculations, allowing for a molecular and electronic comprehensive analysis of the ET process in both complexes. Our results, consistent with experimental mutational data, reveal the ET in FNR/Fd proceeding through a bridge-mediated mechanism in a dominant protein-protein complex, where transfer of the electron is facilitated by Fd loop-residues 40-49. In FNR/Fld, however, we observe a direct transfer between redox cofactors and less complex specificity than in Fd; more than one orientation in the encounter complex can be efficient in ET.
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11
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Affiliation(s)
- Russ Hille
- Department of Biochemistry, University of California, Riverside, Riverside, California 92521, United States
| | - James Hall
- Department of Biochemistry, University of California, Riverside, Riverside, California 92521, United States
| | - Partha Basu
- Department of Chemistry and Biochemistry, Duquesne University, Pittsburgh, Pennsylvania 15282, United States
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12
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Winkler M, Kawelke S, Happe T. Light driven hydrogen production in protein based semi-artificial systems. BIORESOURCE TECHNOLOGY 2011; 102:8493-8500. [PMID: 21696949 DOI: 10.1016/j.biortech.2011.05.019] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/24/2010] [Revised: 05/04/2011] [Accepted: 05/08/2011] [Indexed: 05/31/2023]
Abstract
Photobiological hydrogen production has recently attracted interest in terms of being a potential source for an alternative energy carrier. Especially the natural light driven hydrogen metabolism of unicellular green algae appears as an attractive blueprint for a clean and potentially unlimited dihydrogen source. However, the efficiency of in vivo systems is limited by physiological and evolutionary constraints and scientists only begin to understand the regulatory networks influencing cellular hydrogen production. A growing number of projects aim at circumventing these limitations by focusing on semi-artificial systems. They reconstitute parts of the native electron transfer chains in vitro, combining photosystem I as a photoactive element with a proton reducing catalytic element such as hydrogenase enzymes or noble metal nanoparticles. This review summarizes various approaches and discusses limitations that have to be overcome in order to establish economically applicable systems.
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Affiliation(s)
- Martin Winkler
- Ruhr-Universität Bochum, Fakultät für Biologie und Biotechnologie, Lehrstuhl für Biochemie der Pflanzen, AG Photobiotechnologie, 44780 Bochum, Germany
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13
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Multiple ferredoxin isoforms in Chlamydomonas reinhardtii – Their role under stress conditions and biotechnological implications. Eur J Cell Biol 2010; 89:998-1004. [DOI: 10.1016/j.ejcb.2010.06.018] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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14
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Winkler M, Kuhlgert S, Hippler M, Happe T. Characterization of the key step for light-driven hydrogen evolution in green algae. J Biol Chem 2009; 284:36620-36627. [PMID: 19846550 DOI: 10.1074/jbc.m109.053496] [Citation(s) in RCA: 78] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Abstract
Under anaerobic conditions, several species of green algae perform a light-dependent hydrogen production catalyzed by a special group of [FeFe] hydrogenases termed HydA. Although highly interesting for biotechnological applications, the direct connection between photosynthetic electron transport and hydrogenase activity is still a matter of speculation. By establishing an in vitro reconstitution system, we demonstrate that the photosynthetic ferredoxin (PetF) is essential for efficient electron transfer between photosystem I and HydA1. To investigate the electrostatic interaction process and electron transfer between PetF and HydA1, we performed site-directed mutagenesis. Kinetic analyses with several site-directed mutagenesis variants of HydA1 and PetF enabled us to localize the respective contact sites. These experiments in combination with in silico docking analyses indicate that electrostatic interactions between the conserved HydA1 residue Lys(396) and the C terminus of PetF as well as between the PetF residue Glu(122) and the N-terminal amino group of HydA1 play a major role in complex formation and electron transfer. Mapping of relevant HydA1 and PetF residues constitutes an important basis for manipulating the physiological photosynthetic electron flow in favor of light-driven H(2) production.
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Affiliation(s)
- Martin Winkler
- Lehrstuhl Biochemie der Pflanzen, AG Photobiotechnologie, Ruhr-Universität Bochum, Universitätsstrasse 150, 44801 Bochum, Germany
| | - Sebastian Kuhlgert
- Institut für Biochemie und Biotechnologie der Pflanzen, Universität Münster, Hindenburgplatz 55, 49143 Münster, Germany
| | - Michael Hippler
- Institut für Biochemie und Biotechnologie der Pflanzen, Universität Münster, Hindenburgplatz 55, 49143 Münster, Germany
| | - Thomas Happe
- Lehrstuhl Biochemie der Pflanzen, AG Photobiotechnologie, Ruhr-Universität Bochum, Universitätsstrasse 150, 44801 Bochum, Germany.
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15
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Binding thermodynamics of ferredoxin:NADP+ reductase: two different protein substrates and one energetics. Biophys J 2009; 96:4966-75. [PMID: 19527656 DOI: 10.1016/j.bpj.2009.02.061] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2008] [Revised: 01/16/2009] [Accepted: 03/18/2009] [Indexed: 11/22/2022] Open
Abstract
The thermodynamics of the formation of binary and ternary complexes between Anabaena PCC 7119 FNR and its substrates, NADP+ and Fd, or Fld, has been studied by ITC. Despite structural dissimilarities, the main difference between Fd and Fld binding to FNR relates to hydrophobicity, reflected in different binding heat capacity and number of water molecules released from the interface. At pH 8, the formation of the binary complexes is both enthalpically and entropically driven, accompanied by the protonation of at least one ionizable group. His299 FNR has been identified as the main responsible for the proton exchange observed. However, at pH 10, where no protonation occurs and intrinsic binding parameters can be obtained, the formation of the binary complexes is entropically driven, with negligible enthalpic contribution. Absence of the FMN cofactor in Fld does not alter significantly the strength of the interaction, but considerably modifies the enthalpic and entropic contributions, suggesting a different binding mode. Ternary complexes show negative cooperativity (6-fold and 11-fold reduction in binding affinity, respectively), and an increase in the enthalpic contribution (more favorable) and a decrease in the entropic contribution (less favorable), with regard to the binary complexes energetics.
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16
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Medina M. Structural and mechanistic aspects of flavoproteins: photosynthetic electron transfer from photosystem I to NADP+. FEBS J 2009; 276:3942-58. [PMID: 19583765 DOI: 10.1111/j.1742-4658.2009.07122.x] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
This minireview covers the research carried out in recent years into different aspects of the function of the flavoproteins involved in cyanobacterial photosynthetic electron transfer from photosystem I to NADP(+), flavodoxin and ferredoxin-NADP(+) reductase. Interactions that stabilize protein-flavin complexes and tailor the midpoint potentials in these proteins, as well as many details of the binding and electron transfer to protein and ligand partners, have been revealed. In addition to their role in photosynthesis, flavodoxin and ferredoxin-NADP(+) reductase are ubiquitous flavoenzymes that deliver NAD(P)H or low midpoint potential one-electron donors to redox-based metabolisms in plastids, mitochondria and bacteria. They are also the basic prototypes for a large family of diflavin electron transferases with common functional and structural properties. Understanding their mechanisms should enable greater comprehension of the many physiological roles played by flavodoxin and ferredoxin-NADP(+) reductase, either free or as modules in multidomain proteins. Many aspects of their biochemistry have been extensively characterized using a combination of site-directed mutagenesis, steady-state and transient kinetics, spectroscopy and X-ray crystallography. Despite these considerable advances, various key features of the structural-function relationship are yet to be explained in molecular terms. Better knowledge of these systems and their particular properties may allow us to envisage several interesting applications of these proteins beyond their physiological functions.
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Affiliation(s)
- Milagros Medina
- Departamento de Bioquímica y Biología Molecular y Celular and BFIF, Universidad de Zaragoza, Spain.
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17
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Paladini DH, Musumeci MA, Carrillo N, Ceccarelli EA. Induced fit and equilibrium dynamics for high catalytic efficiency in ferredoxin-NADP(H) reductases. Biochemistry 2009; 48:5760-8. [PMID: 19435322 DOI: 10.1021/bi9004232] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Ferredoxin-NADP(H) reductase (FNR) is a FAD-containing protein that catalyzes the reversible transfer of electrons between NADP(H) and ferredoxin or flavodoxin. This enzyme participates in the redox-based metabolism of plastids, mitochondria, and bacteria. Plastidic plant-type FNRs are very efficient reductases in supporting photosynthesis. They have a strong preference for NADP(H) over NAD(H), consistent with the main physiological role of NADP(+) photoreduction. In contrast, FNRs from organisms with heterotrophic metabolisms or anoxygenic photosynthesis display turnover rates that are up to 100-fold lower than those of their plastidic and cyanobacterial counterparts. With the aim of elucidating the mechanisms by which plastidic enzymes achieve such high catalytic efficiencies and NADP(H) specificity, we investigated the manner in which the NADP(H) nicotinamide enters and properly binds to the catalytic site. Analyzing the interaction of different nucleotides, substrate analogues, and aromatic compounds with the wild type and the mutant Y308S-FNR from pea, we found that the interaction of the 2'-P-AMP moiety from NADP(+) induces a change that favors the interaction of the nicotinamide, thereby facilitating the catalytic process. Furthermore, the main role of the terminal tyrosine, Y308, is to destabilize the interaction of the nicotinamide with the enzyme, inducing product release and favoring discrimination of the nucleotide substrate. We determined that this function can be replaced by the addition of aromatic compounds that freely diffuse in solution and establish a dynamic equilibrium, reversing the effect of the mutation in the Y308S-FNR mutant.
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Affiliation(s)
- Darío H Paladini
- Molecular Biology Division, Instituto de Biología Molecular y Celular de Rosario (IBR), CONICET, Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Suipacha 531, S2002LRK Rosario, Argentina
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18
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Medina M, Abagyan R, Gómez-Moreno C, Fernandez-Recio J. Docking analysis of transient complexes: interaction of ferredoxin-NADP+ reductase with ferredoxin and flavodoxin. Proteins 2008; 72:848-62. [PMID: 18260112 DOI: 10.1002/prot.21979] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Ferredoxin (Fd) interacts with ferredoxin-NADP(+) reductase (FNR) to transfer two electrons to the latter, one by one, which will finally be used to reduce NADP(+) to NADPH. The formation of a transient complex between Fd and FNR is required for the electron transfer (ET), and extensive mutational and crystallographic studies have been reported to characterize such protein-protein interaction. However, some aspects of the association mechanism still remain unclear. Moreover, in spite of their structural differences, flavodoxin (Fld) can replace Fd in its function and interact with FNR to transfer electrons with only slightly lower efficiency. Although crystallographic structures for the FNR:Fd association have been reported, experimental structural data for the FNR:Fld interaction are highly elusive. We have modeled here the interactions between FNR and both of its protein partners, Fd and Fld, using surface energy analysis, computational rigid-body docking simulations, and interface side-chain refinement. The results, consistent with previous experimental data, suggest the existence of alternative binding modes in these ET proteins.
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Affiliation(s)
- Milagros Medina
- Department of Biochemistry and Molecular and Cellular Biology, University of Zaragoza, Zaragoza, Spain
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19
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Aliverti A, Pandini V, Pennati A, de Rosa M, Zanetti G. Structural and functional diversity of ferredoxin-NADP(+) reductases. Arch Biochem Biophys 2008; 474:283-91. [PMID: 18307973 DOI: 10.1016/j.abb.2008.02.014] [Citation(s) in RCA: 118] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2007] [Revised: 02/07/2008] [Accepted: 02/11/2008] [Indexed: 11/29/2022]
Abstract
Although all ferredoxin-NADP(+) reductases (FNRs) catalyze the same reaction, i.e. the transfer of reducing equivalents between NADP(H) and ferredoxin, they belong to two unrelated families of proteins: the plant-type and the glutathione reductase-type of FNRs. Aim of this review is to provide a general classification scheme for these enzymes, to be used as a framework for the comparison of their properties. Furthermore, we report on some recent findings, which significantly increased the understanding of the structure-function relationships of FNRs, i.e. the ability of adrenodoxin reductase and its homologs to catalyze the oxidation of NADP(+) to its 4-oxo derivative, and the properties of plant-type FNRs from non-photosynthetic organisms. Plant-type FNRs from bacteria and Apicomplexan parasites provide examples of novel ways of FAD- and NADP(H)-binding. The recent characterization of an FNR from Plasmodium falciparum brings these enzymes into the field of drug design.
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Affiliation(s)
- Alessandro Aliverti
- Dipartimento di Scienze Biomolecolari e Biotecnologie, Università degli Studi di Milano, via Celoria 26, 20133 Milano, Italy.
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20
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Frago S, Goñi G, Herguedas B, Peregrina JR, Serrano A, Perez-Dorado I, Molina R, Gómez-Moreno C, Hermoso JA, Martínez-Júlvez M, Mayhew SG, Medina M. Tuning of the FMN binding and oxido-reduction properties by neighboring side chains in Anabaena flavodoxin. Arch Biochem Biophys 2007; 467:206-17. [PMID: 17904516 DOI: 10.1016/j.abb.2007.08.024] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2007] [Revised: 08/13/2007] [Accepted: 08/13/2007] [Indexed: 11/23/2022]
Abstract
Contribution of three regions (phosphate-binding, 50's and 90's loops) of Anabaena apoflavodoxin to FMN binding and reduction potential was studied. Thr12 and Glu16 did not influence FMN redox properties, but Thr12 played a role in FMN binding. Replacement of Trp57 with Glu, Lys or Arg moderately shifted E(ox/sq) and E(sq/hq) and altered the energetic of the FMN redox states binding profile. Our data indicate that the side chain of position 57 does not modulate E(ox/sq) by aromatic stacking or solvent exclusion, but rather by influencing the relative strength of the H-bond between the N(5) of the flavin and the Asn58-Ile59 bond. A correlation was observed between the isoalloxazine increase in solvent accessibility and less negative E(sq/hq). Moreover, E(sq/hq) became less negative as positively charged residues were added near to the isoalloxazine. Ile59 and Ile92 were simultaneously mutated to Ala or Glu. These mutations impaired FMN binding, while shifting E(sq/hq) to less negative values and E(ox/sq) to more negative. These effects are discussed on the bases of the X-ray structures of some of the Fld mutants, suggesting that in Anabaena Fld the structural control of both electron transfer steps is much more subtle than in other Flds.
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Affiliation(s)
- Susana Frago
- Departamento de Bioquímica y Biología Molecular y Celular, Facultad de Ciencias, Universidad de Zaragoza, 50009-Zaragoza, Spain
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Iyanagi T. Molecular mechanism of phase I and phase II drug-metabolizing enzymes: implications for detoxification. ACTA ACUST UNITED AC 2007; 260:35-112. [PMID: 17482904 DOI: 10.1016/s0074-7696(06)60002-8] [Citation(s) in RCA: 152] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Enzymes that catalyze the biotransformation of drugs and xenobiotics are generally referred to as drug-metabolizing enzymes (DMEs). DMEs can be classified into two main groups: oxidative or conjugative. The NADPH-cytochrome P450 reductase (P450R)/cytochrome P450 (P450) electron transfer systems are oxidative enzymes that mediate phase I reactions, whereas the UDP-glucuronosyltransferases (UGTs) are conjugative enzymes that mediate phase II enzymes. Both enzyme systems are localized to the endoplasmic reticulum (ER) where a number of drugs are sequentially metabolized. DMEs, including P450s and UGTs, generally have a highly plastic active site that can accommodate a wide variety of substrates. The P450 and UGT genes constitute a supergene family, in which UGT proteins are encoded by distinct genes and a complex gene. Both the P450 and UGT genes have evolved to diversify their functions. This chapter reviews advances in understanding the structure and function of the P450R/P450 and UGT enzyme systems. In particular, the coordinate biotransformation of xenobiotics by phase I and II enzymes in the ER membrane is examined.
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Affiliation(s)
- Takashi Iyanagi
- Biometal Science Laboratory, RIKEN SPring-8 Center, Harima Institute, Hyogo 679-5148, Japan
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Velazquez-Campoy A, Goñi G, Peregrina JR, Medina M. Exact analysis of heterotropic interactions in proteins: Characterization of cooperative ligand binding by isothermal titration calorimetry. Biophys J 2006; 91:1887-904. [PMID: 16766617 PMCID: PMC1544317 DOI: 10.1529/biophysj.106.086561] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Intramolecular interaction networks in proteins are responsible for heterotropic ligand binding cooperativity, a biologically important, widespread phenomenon in nature (e.g., signaling transduction cascades, enzymatic cofactors, enzymatic allosteric activators or inhibitors, gene transcription, or repression). The cooperative binding of two (or more) different ligands to a macromolecule is the underlying principle. To date, heterotropic effects have been studied mainly kinetically in enzymatic systems. Until now, approximate approaches have been employed for studying equilibrium heterotropic ligand binding effects, except in two special cases in which an exact analysis was developed: independent binding (no cooperativity) and competitive binding (maximal negative cooperativity). The exact analysis and methodology for characterizing ligand binding cooperativity interactions in the general case (any degree of cooperativity) using isothermal titration calorimetry are presented in this work. Intramolecular interaction pathways within the allosteric macromolecule can be identified and characterized using this methodology. As an example, the thermodynamic characterization of the binding interaction between ferredoxin-NADP+ reductase and its three substrates, NADP+, ferredoxin, and flavodoxin, as well as the characterization of their binding cooperativity interaction, is presented.
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Affiliation(s)
- Adrian Velazquez-Campoy
- Institute of Biocomputation and Complex Systems Physics (BIFI), Universidad de Zaragoza, Zaragoza, Spain.
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