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Lublin V, Kauffmann B, Engilberge S, Durola F, Gounel S, Bichon S, Jean C, Mano N, Giraud MF, Chavas L, Thureau A, Thompson A, Stines-Chaumeil C. Does Acinetobacter calcoaceticus glucose dehydrogenase produce self-damaging H2O2? Biosci Rep 2024; 44:BSR20240102. [PMID: 38687614 PMCID: PMC11130540 DOI: 10.1042/bsr20240102] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2024] [Revised: 04/25/2024] [Accepted: 04/30/2024] [Indexed: 05/02/2024] Open
Abstract
The soluble glucose dehydrogenase (sGDH) from Acinetobacter calcoaceticus has been widely studied and is used, in biosensors, to detect the presence of glucose, taking advantage of its high turnover and insensitivity to molecular oxygen. This approach, however, presents two drawbacks: the enzyme has broad substrate specificity (leading to imprecise blood glucose measurements) and shows instability over time (inferior to other oxidizing glucose enzymes). We report the characterization of two sGDH mutants: the single mutant Y343F and the double mutant D143E/Y343F. The mutants present enzyme selectivity and specificity of 1.2 (Y343F) and 5.7 (D143E/Y343F) times higher for glucose compared with that of the wild-type. Crystallographic experiments, designed to characterize these mutants, surprisingly revealed that the prosthetic group PQQ (pyrroloquinoline quinone), essential for the enzymatic activity, is in a cleaved form for both wild-type and mutant structures. We provide evidence suggesting that the sGDH produces H2O2, the level of production depending on the mutation. In addition, spectroscopic experiments allowed us to follow the self-degradation of the prosthetic group and the disappearance of sGDH's glucose oxidation activity. These studies suggest that the enzyme is sensitive to its self-production of H2O2. We show that the premature aging of sGDH can be slowed down by adding catalase to consume the H2O2 produced, allowing the design of a more stable biosensor over time. Our research opens questions about the mechanism of H2O2 production and the physiological role of this activity by sGDH.
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Affiliation(s)
- Victoria Lublin
- Centre de Recherche Paul Pascal (CRPP), University Bordeaux, CNRS, UMR 5031, Pessac, France
- Synchrotron SOLEIL (CNRS - CEA), Saint-Aubin, France
| | - Brice Kauffmann
- Institut Européen de Chimie et Biologie (IECB), Univ. Bordeaux, CNRS, INSERM, US1, UAR 3033, Pessac, France
| | - Sylvain Engilberge
- Univ. Grenoble Alpes, CNRS, CEA, Institut de Biologie Structurale (IBS), 71 avenue des Martyrs, Grenoble 38044, France
| | - Fabien Durola
- Centre de Recherche Paul Pascal (CRPP), University Bordeaux, CNRS, UMR 5031, Pessac, France
| | - Sébastien Gounel
- Centre de Recherche Paul Pascal (CRPP), University Bordeaux, CNRS, UMR 5031, Pessac, France
| | - Sabrina Bichon
- Centre de Recherche Paul Pascal (CRPP), University Bordeaux, CNRS, UMR 5031, Pessac, France
| | - Cloée Jean
- Centre de Recherche Paul Pascal (CRPP), University Bordeaux, CNRS, UMR 5031, Pessac, France
| | - Nicolas Mano
- Centre de Recherche Paul Pascal (CRPP), University Bordeaux, CNRS, UMR 5031, Pessac, France
| | - Marie-France Giraud
- Institute of Chemistry and Biology of Membranes and Nano-objects (CBMN), Pessac, France
| | | | | | | | - Claire Stines-Chaumeil
- Centre de Recherche Paul Pascal (CRPP), University Bordeaux, CNRS, UMR 5031, Pessac, France
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2
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Okuda-Shimazaki J, Yoshida H, Lee I, Kojima K, Suzuki N, Tsugawa W, Yamada M, Inaka K, Tanaka H, Sode K. Microgravity environment grown crystal structure information based engineering of direct electron transfer type glucose dehydrogenase. Commun Biol 2022; 5:1334. [PMID: 36473944 PMCID: PMC9727119 DOI: 10.1038/s42003-022-04286-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2022] [Accepted: 11/21/2022] [Indexed: 12/12/2022] Open
Abstract
The heterotrimeric flavin adenine dinucleotide dependent glucose dehydrogenase is a promising enzyme for direct electron transfer (DET) principle-based glucose sensors within continuous glucose monitoring systems. We elucidate the structure of the subunit interface of this enzyme by preparing heterotrimer complex protein crystals grown under a space microgravity environment. Based on the proposed structure, we introduce inter-subunit disulfide bonds between the small and electron transfer subunits (5 pairs), as well as the catalytic and the electron transfer subunits (9 pairs). Without compromising the enzyme's catalytic efficiency, a mutant enzyme harboring Pro205Cys in the catalytic subunit, Asp383Cys and Tyr349Cys in the electron transfer subunit, and Lys155Cys in the small subunit, is determined to be the most stable of the variants. The developed engineered enzyme demonstrate a higher catalytic activity and DET ability than the wild type. This mutant retains its full activity below 70 °C as well as after incubation at 75 °C for 15 min - much higher temperatures than the current gold standard enzyme, glucose oxidase, is capable of withstanding.
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Affiliation(s)
- Junko Okuda-Shimazaki
- grid.10698.360000000122483208Joint Department of Biomedical Engineering, The University of North Carolina at Chapel Hill and North Carolina State University, Chapel Hill, NC27599 USA
| | - Hiromi Yoshida
- grid.258331.e0000 0000 8662 309XDepartment of Basic Life Science, Faculty of Medicine, Kagawa University, 1750-1 Ikenobe, Miki-cho, Kita-gun, Kagawa 761-0793 Japan
| | - Inyoung Lee
- grid.10698.360000000122483208Joint Department of Biomedical Engineering, The University of North Carolina at Chapel Hill and North Carolina State University, Chapel Hill, NC27599 USA
| | - Katsuhiro Kojima
- grid.136594.c0000 0001 0689 5974Graduate School of Engineering, Department of Biotechnology and Life Science, Tokyo University of Agriculture and Technology, Koganei, Tokyo 184-8588 Japan
| | - Nanoha Suzuki
- grid.136594.c0000 0001 0689 5974Graduate School of Engineering, Department of Biotechnology and Life Science, Tokyo University of Agriculture and Technology, Koganei, Tokyo 184-8588 Japan
| | - Wakako Tsugawa
- grid.136594.c0000 0001 0689 5974Graduate School of Engineering, Department of Biotechnology and Life Science, Tokyo University of Agriculture and Technology, Koganei, Tokyo 184-8588 Japan
| | - Mitsugu Yamada
- grid.62167.340000 0001 2220 7916JEM Utilization Center Human Spaceflight Technology Directorate, Japan Aerospace Exploration Agency (JAXA), 2-1-1 Sengen, Tsukuba-shi, Ibaraki 305-8505 Japan
| | - Koji Inaka
- grid.459744.fMaruwa Foods and Biosciences, 170-1 Tsutsui-cho, Yamato Koriyama-shi, Nara 639-1123 Japan
| | - Hiroaki Tanaka
- grid.459486.2Confocal Science Inc., Musashino Bldg, 5-14-15 Fukasawa, Setagaya-ku, Tokyo 158-0081 Japan
| | - Koji Sode
- grid.10698.360000000122483208Joint Department of Biomedical Engineering, The University of North Carolina at Chapel Hill and North Carolina State University, Chapel Hill, NC27599 USA
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3
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Extending galactose-oxidation pathway of Pseudomonas putida for utilization of galactose-rich red macroalgae as sustainable feedstock. J Biotechnol 2022; 348:1-9. [DOI: 10.1016/j.jbiotec.2022.02.009] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2021] [Revised: 02/21/2022] [Accepted: 02/23/2022] [Indexed: 12/23/2022]
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4
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Bioelectrocatalysis based on direct electron transfer of fungal pyrroloquinoline quinone-dependent dehydrogenase lacking the cytochrome domain. Electrochim Acta 2020. [DOI: 10.1016/j.electacta.2020.136982] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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5
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PQQ-GDH - Structure, function and application in bioelectrochemistry. Bioelectrochemistry 2020; 134:107496. [PMID: 32247165 DOI: 10.1016/j.bioelechem.2020.107496] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2019] [Revised: 03/01/2020] [Accepted: 03/02/2020] [Indexed: 12/16/2022]
Abstract
This review summarizes the basic features of the PQQ-GDH enzyme as one of the sugar converting biocatalysts. Focus is on the membrane -bound and the soluble form. Furthermore, the main principles of enzymatic catalysis as well as studies on the physiological importance are reviewed. A short overview is given on developments in protein engineering. The major part, however, deals with the different fields of application in bioelectrochemistry. This includes approaches for enzyme-electrode communication such as direct electron transfer, mediator-based systems, redox polymers or conducting polymers and holoenzyme reconstitution, and covers applied areas such as biosensing, biofuel cells, recycling schemes, enzyme competition, light-directed sensing, switchable detection schemes, logical operations by enzyme electrodes and immune sensing.
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6
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Carpenter AC, Paulsen IT, Williams TC. Blueprints for Biosensors: Design, Limitations, and Applications. Genes (Basel) 2018; 9:E375. [PMID: 30050028 PMCID: PMC6115959 DOI: 10.3390/genes9080375] [Citation(s) in RCA: 70] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2018] [Revised: 07/23/2018] [Accepted: 07/23/2018] [Indexed: 12/12/2022] Open
Abstract
Biosensors are enabling major advances in the field of analytics that are both facilitating and being facilitated by advances in synthetic biology. The ability of biosensors to rapidly and specifically detect a wide range of molecules makes them highly relevant to a range of industrial, medical, ecological, and scientific applications. Approaches to biosensor design are as diverse as their applications, with major biosensor classes including nucleic acids, proteins, and transcription factors. Each of these biosensor types has advantages and limitations based on the intended application, and the parameters that are required for optimal performance. Specifically, the choice of biosensor design must consider factors such as the ligand specificity, sensitivity, dynamic range, functional range, mode of output, time of activation, ease of use, and ease of engineering. This review discusses the rationale for designing the major classes of biosensor in the context of their limitations and assesses their suitability to different areas of biotechnological application.
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Affiliation(s)
- Alexander C Carpenter
- Department of Molecular Sciences, Macquarie University, Sydney, NSW 2109, Australia.
- CSIRO Synthetic Biology Future Science Platform, Canberra, ACT 2601, Australia.
| | - Ian T Paulsen
- Department of Molecular Sciences, Macquarie University, Sydney, NSW 2109, Australia.
| | - Thomas C Williams
- Department of Molecular Sciences, Macquarie University, Sydney, NSW 2109, Australia.
- CSIRO Synthetic Biology Future Science Platform, Canberra, ACT 2601, Australia.
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7
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Wehrmann M, Klebensberger J. Engineering thermal stability and solvent tolerance of the soluble quinoprotein PedE from Pseudomonas putida KT2440 with a heterologous whole-cell screening approach. Microb Biotechnol 2018; 11:399-408. [PMID: 29239114 PMCID: PMC5812247 DOI: 10.1111/1751-7915.13036] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2017] [Revised: 10/18/2017] [Accepted: 11/12/2017] [Indexed: 12/16/2022] Open
Abstract
Due to their ability for direct electron transfer to electrodes, the utilization of rare earth metals as cofactor, and their periplasmic localization, pyrroloquinoline quinone-dependent alcohol dehydrogenases (PQQ-ADHs) represent an interesting class of biocatalysts for various biotechnological applications. For most biocatalysts protein stability is crucial, either to increase the performance of the protein under a given process condition or to maximize robustness of the protein towards mutational manipulations, which are often needed to enhance or introduce a functionality of interest. In this study, we describe a whole-cell screening assay, suitable for probing PQQ-ADH activities in Escherichia coli BL21(DE3) cells, and use this assay to screen smart mutant libraries for increased thermal stability of the PQQ-ADH PedE (PP_2674) from Pseudomonas putida KT2440. Upon three consecutive rounds of screening, we identified three different amino acid positions, which significantly improve enzyme stability. The subsequent combination of the beneficial mutations finally results in the triple mutant R91D/E408P/N410K, which not only exhibits a 7°C increase in thermal stability but also a twofold increase in residual activity upon incubation with up to 50% dimethyl sulfoxide (DMSO), while showing no significant difference in enzymatic efficiency (kcat /KM ).
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Affiliation(s)
- Matthias Wehrmann
- Institute of Technical BiochemistryUniversity of StuttgartStuttgartGermany
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8
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Tremey E, Stines-Chaumeil C, Gounel S, Mano N. Designing an O2
-Insensitive Glucose Oxidase for Improved Electrochemical Applications. ChemElectroChem 2017. [DOI: 10.1002/celc.201700646] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Affiliation(s)
- Emilie Tremey
- CNRS, CRPP - UPR 8641; 115 Avenue du Docteur Schweitzer 33600 Pessac France
- Univ Bordeaux; 146 rue Léo Saignat 33076 Bordeaux Cedex France
| | - Claire Stines-Chaumeil
- CNRS, CRPP - UPR 8641; 115 Avenue du Docteur Schweitzer 33600 Pessac France
- Univ Bordeaux; 146 rue Léo Saignat 33076 Bordeaux Cedex France
| | - Sébastien Gounel
- CNRS, CRPP - UPR 8641; 115 Avenue du Docteur Schweitzer 33600 Pessac France
- Univ Bordeaux; 146 rue Léo Saignat 33076 Bordeaux Cedex France
| | - Nicolas Mano
- CNRS, CRPP - UPR 8641; 115 Avenue du Docteur Schweitzer 33600 Pessac France
- Univ Bordeaux; 146 rue Léo Saignat 33076 Bordeaux Cedex France
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9
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Ortiz R, Rahman M, Zangrilli B, Sygmund C, Micheelsen PO, Silow M, Toscano MD, Ludwig R, Gorton L. Engineering of Cellobiose Dehydrogenases for Improved Glucose Sensitivity and Reduced Maltose Affinity. ChemElectroChem 2017. [DOI: 10.1002/celc.201600781] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Affiliation(s)
- Roberto Ortiz
- Department of Analytical Chemistry/Biochemistry and Structural Biology; Lund University; P. O. Box 124 SE-22100 Lund Sweden
- Department of Chemistry; Kemitorvet, DTU 2800 Kgs. Lyngby Denmark
| | - Mahbubur Rahman
- Department of Analytical Chemistry/Biochemistry and Structural Biology; Lund University; P. O. Box 124 SE-22100 Lund Sweden
| | - Beatrice Zangrilli
- Department of Analytical Chemistry/Biochemistry and Structural Biology; Lund University; P. O. Box 124 SE-22100 Lund Sweden
| | - Christoph Sygmund
- Department of Food Science and Technology; BOKU-University of Natural Resources and Life Sciences; Muthgasse 18 A-1190 Vienna Austria
| | | | - Maria Silow
- Novozymes A/S; Krogshøgvej 36, DTU 2880 Bagsvœrd Denmark
| | | | - Roland Ludwig
- Department of Food Science and Technology; BOKU-University of Natural Resources and Life Sciences; Muthgasse 18 A-1190 Vienna Austria
| | - Lo Gorton
- Department of Analytical Chemistry/Biochemistry and Structural Biology; Lund University; P. O. Box 124 SE-22100 Lund Sweden
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10
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Guo Z, Johnston WA, Stein V, Kalimuthu P, Perez-Alcala S, Bernhardt PV, Alexandrov K. Engineering PQQ-glucose dehydrogenase into an allosteric electrochemical Ca2+ sensor. Chem Commun (Camb) 2016; 52:485-8. [DOI: 10.1039/c5cc07824e] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Electrochemical biosensors convert biological events to an electrical current.
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Affiliation(s)
- Zhong Guo
- Institute for Molecular Bioscience
- The University of Queensland
- Brisbane
- Australia
| | - Wayne A. Johnston
- Institute for Molecular Bioscience
- The University of Queensland
- Brisbane
- Australia
| | - Viktor Stein
- Institute for Molecular Bioscience
- The University of Queensland
- Brisbane
- Australia
| | - Palraj Kalimuthu
- School of Chemistry and Molecular Biosciences
- The University of Queensland
- Brisbane
- Australia
| | | | - Paul V. Bernhardt
- School of Chemistry and Molecular Biosciences
- The University of Queensland
- Brisbane
- Australia
| | - Kirill Alexandrov
- Institute for Molecular Bioscience
- The University of Queensland
- Brisbane
- Australia
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11
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Mehtiö T, Toivari M, Wiebe MG, Harlin A, Penttilä M, Koivula A. Production and applications of carbohydrate-derived sugar acids as generic biobased chemicals. Crit Rev Biotechnol 2015; 36:904-16. [DOI: 10.3109/07388551.2015.1060189] [Citation(s) in RCA: 64] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Affiliation(s)
- Tuomas Mehtiö
- VTT Technical Research Centre of Finland, Espoo, Finland
| | - Mervi Toivari
- VTT Technical Research Centre of Finland, Espoo, Finland
| | | | - Ali Harlin
- VTT Technical Research Centre of Finland, Espoo, Finland
| | - Merja Penttilä
- VTT Technical Research Centre of Finland, Espoo, Finland
| | - Anu Koivula
- VTT Technical Research Centre of Finland, Espoo, Finland
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12
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Vajdič T, Ošlaj M, Kopitar G, Mrak P. Engineered, highly productive biosynthesis of artificial, lactonized statin side-chain building blocks: The hidden potential of Escherichia coli unleashed. Metab Eng 2014; 24:160-72. [DOI: 10.1016/j.ymben.2014.05.012] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2014] [Revised: 04/22/2014] [Accepted: 05/06/2014] [Indexed: 12/26/2022]
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13
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Screening of peptide ligands for pyrroloquinoline quinone glucose dehydrogenase using antagonistic template-based biopanning. Int J Mol Sci 2013; 14:23244-56. [PMID: 24287902 PMCID: PMC3876041 DOI: 10.3390/ijms141223244] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2013] [Revised: 10/31/2013] [Accepted: 11/11/2013] [Indexed: 01/05/2023] Open
Abstract
We have developed a novel method, antagonistic template-based biopanning, for screening peptide ligands specifically recognizing local tertiary protein structures. We chose water-soluble pyrroloquinoline quinone (PQQ) glucose dehydrogenase (GDH-B) as a model enzyme for this screening. Two GDH-B mutants were constructed as antagonistic templates; these have some point mutations to induce disruption of local tertiary structures within the loop regions that are located at near glucose-binding pocket. Using phage display, we selected 12-mer peptides that specifically bound to wild-type GDH-B but not to the antagonistic templates. Consequently, a peptide ligand showing inhibitory activity against GDH-B was obtained. These results demonstrate that the antagonistic template-based biopanning is useful for screening peptide ligands recognizing the specific local tertiary structure of proteins.
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14
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A pyrroloquinolinequinone-dependent glucose dehydrogenase (PQQ-GDH)-electrode with direct electron transfer based on polyaniline modified carbon nanotubes for biofuel cell application. Electrochim Acta 2012. [DOI: 10.1016/j.electacta.2012.03.128] [Citation(s) in RCA: 66] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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15
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Nishioka T, Yasutake Y, Nishiya Y, Tamura T. Structure-guided mutagenesis for the improvement of substrate specificity ofBacillus megateriumglucose 1-dehydrogenase IV. FEBS J 2012; 279:3264-75. [DOI: 10.1111/j.1742-4658.2012.08713.x] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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16
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Effects of membrane-bound glucose dehydrogenase overproduction on the respiratory chain of Gluconobacter oxydans. Appl Microbiol Biotechnol 2012; 97:3457-66. [PMID: 22790543 DOI: 10.1007/s00253-012-4265-z] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2012] [Revised: 06/19/2012] [Accepted: 06/23/2012] [Indexed: 10/28/2022]
Abstract
The acetic acid bacterium Gluconobacter oxydans incompletely oxidizes carbon sources as a natural part of its metabolism, and this feature has been exploited for many biotechnological applications. The most important enzymes used to harness the biocatalytic oxidative capacity of G. oxydans are the pyrroloquinoline quinone (PQQ)-dependent dehydrogenases. The membrane-bound PQQ-dependent glucose dehydrogenase (mGDH), encoded by gox0265, was used as model protein for homologous membrane protein production using the previously described Gluconobacter expression vector pBBR1p452. The mgdh gene had ninefold higher expression in the overproduction strain compared to the parental strain. Furthermore, membranes from the overexpression strain had a five- and threefold increase of mGDH activity and oxygen consumption rates, respectively. Oxygen consumption rate of the membrane fraction could not be increased by the addition of a substrate combination of glucose and ethanol in the overproduction strain, indicating that the terminal quinol oxidases of the respiratory chain were rate limiting. In contrast, addition of glucose and ethanol to membranes of the control strain increased oxygen consumption rates approaching the observed rates with G. oxydans overproducing mGDH. The higher glucose oxidation rates of the mGDH overproduction strain corresponded to a 70 % increase of the gluconate production rate compared to the control strain. The high rate of glucose oxidation may be useful in the industrial production of gluconates and ketogluconates, or as whole-cell biosensors. Furthermore, mGDH was purified to homogeneity by one-step strep-tactin affinity chromatography and characterized. To our knowledge, this is the first report of a membrane integral quinoprotein being purified by affinity chromatography and serves as a proof-of-principle for using G. oxydans as a host for membrane protein expression and purification.
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17
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Yu Y, Wei P, Zhu X, Huang L, Cai J, Xu Z. High-level production of soluble pyrroloquinoline quinone-dependent glucose dehydrogenase inEscherichia coli. Eng Life Sci 2012. [DOI: 10.1002/elsc.201100224] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Affiliation(s)
- Yi Yu
- Department of Chemical and Biological Engineering; Institute of Biological Engineering; Zhejiang University; Hangzhou; P. R. China
| | - Peilian Wei
- Department of Biochemical Engineering; Zhejiang University of Science and Technology; Hangzhou; P. R. China
| | - Xiangcheng Zhu
- Hunan Engineering Research Center of Combinatorial Biosynthesis and Natural Product Drug Discovery; Changsha; Hunan; P. R. China
| | - Lei Huang
- Department of Chemical and Biological Engineering; Institute of Biological Engineering; Zhejiang University; Hangzhou; P. R. China
| | - Jin Cai
- Department of Chemical and Biological Engineering; Institute of Biological Engineering; Zhejiang University; Hangzhou; P. R. China
| | - Zhinan Xu
- Department of Chemical and Biological Engineering; Institute of Biological Engineering; Zhejiang University; Hangzhou; P. R. China
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18
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Durand F, Limoges B, Mano N, Mavré F, Miranda-Castro R, Savéant JM. Effect of substrate inhibition and cooperativity on the electrochemical responses of glucose dehydrogenase. Kinetic characterization of wild and mutant types. J Am Chem Soc 2011; 133:12801-9. [PMID: 21780841 DOI: 10.1021/ja204637d] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Thanks to its insensitivity to dioxygen and to its good catalytic reactivity, and in spite of its poor substrate selectivity, quinoprotein glucose dehydrogenase (PQQ-GDH) plays a prominent role among the redox enzymes that can be used for analytical purposes, such as glucose detection, enzyme-based bioaffinity assays, and the design of biofuel cells. A detailed kinetic analysis of the electrochemical catalytic responses, leading to an unambiguous characterization of each individual steps, seems a priori intractable in view of the interference, on top of the usual ping-pong mechanism, of substrate inhibition and of cooperativity effects between the two identical subunits of the enzyme. Based on simplifications suggested by extended knowledge previously acquired by standard homogeneous kinetics, it is shown that analysis of the catalytic responses obtained by means of electrochemical nondestructive techniques, such as cyclic voltammetry, with ferrocene methanol as a mediator, does allow a full characterization of all individual steps of the catalytic reaction, including substrate inhibition and cooperativity and, thus, allows to decipher the reason that makes the enzyme more efficient when the neighboring subunit is filled with a glucose molecule. As a first practical illustration of this electrochemical approach, comparison of the native enzyme responses with those of a mutant (in which the asparagine amino acid in position 428 has been replaced by a cysteine residue) allowed identification of the elementary steps that makes the mutant type more efficient than the wild type when cooperativity between the two subunits takes place, which is observed at large mediator and substrate concentrations. A route is thus opened to structure-reactivity relationships and therefore to mutagenesis strategies aiming at better performances in terms of catalytic responses and/or substrate selectivity.
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Affiliation(s)
- Fabien Durand
- Centre de Recherche Paul Pascal, Universit de Bordeaux, UPR 8641, Avenue Albert Schweitzer, 33600 Pessac, France
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19
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Flexer V, Durand F, Tsujimura S, Mano N. Efficient direct electron transfer of PQQ-glucose dehydrogenase on carbon cryogel electrodes at neutral pH. Anal Chem 2011; 83:5721-7. [PMID: 21662989 DOI: 10.1021/ac200981r] [Citation(s) in RCA: 81] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
We present a comprehensive study of the direct electron transfer reaction of soluble PQQ-GDH from Acinetobacter calcoaceticus. Wild-type PQQ-sGDH nonspecifically adsorbed on carbon cryogel electrodes retained its enzymatic activity for glucose and maltose oxidation at pH 7.2 and 37 °C. The cyclic voltammograms in the absence of enzymatic substrate showed 2 redox peaks that suggest a two-step, one-electron oxidation/reduction of PQQ. Calibration curves showed a linear amperometric response for a wide glucose concentration range, including the values normally found in blood. At saturation, the catalytic current reached 0.93 mA cm(-2). Altogether the experimental results suggest that the amperometric output of the electrodes and the shape of the calibration curves represent a combination of the intrinsic enzyme kinetics, the maximum rate of heterogeneous electron transfer and the substrate accessibility to the enzyme's active center caused by the confinement of the enzyme into the mesoporous structure. A new mutant enzyme, N428C, developed in our group that shows almost twice the maximum catalytic activity in homogeneous experiments in solution, also showed a DET signal on carbon cryogel electrodes for glucose electro-oxidation. The higher activity for the mutant enzyme was also verified on the electrode surface.
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Affiliation(s)
- Victoria Flexer
- Université de Bordeaux, Centre de Recherche Paul Pascal, CRPP-UPR 8641-CNRS, Pessac, France
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Durand F, Stines-Chaumeil C, Flexer V, André I, Mano N. Designing a highly active soluble PQQ-glucose dehydrogenase for efficient glucose biosensors and biofuel cells. Biochem Biophys Res Commun 2010; 402:750-4. [PMID: 21036156 DOI: 10.1016/j.bbrc.2010.10.102] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2010] [Accepted: 10/24/2010] [Indexed: 11/16/2022]
Abstract
We report for the first time a soluble PQQ-glucose dehydrogenase that is twice more active than the wild type for glucose oxidation and was obtained by combining site directed mutagenesis, modelling and steady-state kinetics. The observed enhancement is attributed to a better interaction between the cofactor and the enzyme leading to a better electron transfer. Electrochemical experiments also demonstrate the superiority of the new mutant for glucose oxidation and make it a promising enzyme for the development of high-performance glucose biosensors and biofuel cells.
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Affiliation(s)
- Fabien Durand
- Université de Bordeaux, Centre de Recherche Paul Pascal (CRPP), UPR 8641, Pessac, France
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21
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Hofer M, Bönsch K, Greiner-Stöffele T, Ballschmiter M. Characterization and Engineering of a Novel Pyrroloquinoline Quinone Dependent Glucose Dehydrogenase from Sorangium cellulosum So ce56. Mol Biotechnol 2010; 47:253-61. [DOI: 10.1007/s12033-010-9339-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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22
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Taneoka A, Sakaguchi-Mikami A, Yamazaki T, Tsugawa W, Sode K. The construction of a glucose-sensing luciferase. Biosens Bioelectron 2009; 25:76-81. [PMID: 19559587 DOI: 10.1016/j.bios.2009.06.004] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2009] [Revised: 05/29/2009] [Accepted: 06/02/2009] [Indexed: 11/18/2022]
Abstract
A novel luminescence-based glucose-sensing molecule was created by combining a galactose-/glucose-binding protein (GGBP) with luciferase. The glucose-sensing luciferase (GlcLuc) was constructed using a GGBP fused with a large domain and a small domain of Firefly luciferase (Lluc and Sluc). The luminescence intensity-based analysis with E. coli recombinant protein showed that the GlcLuc had luciferase activity in glucose or galactose in a concentration-dependent manner (K(d)=3.9 microM for glucose and 11 microM for galactose), and that the increase in the activity saturated within one minute after the injection of the ligands. These results indicated that the conformation change of the GGBP moiety following the ligand binding effectively induced the reconstitution of the GGBP-fused split luciferase. The Asp459Asn mutation, which was expected to lead to a glucose specific binding ability, was then introduced into the GlcLuc. The GlcLuc mutant showed the luciferase activity increasing only with the increase of glucose concentration, but not with that of galactose. Our results demonstrate that the GGBP fused with a split luciferase, which is reconstituted rapidly and specifically in the presence of glucose, provides a novel glucose-sensing system based on luminescence and may also contribute to the construction of luminescence-based sensing molecules for other substrates using other PBPs.
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Affiliation(s)
- Atsushi Taneoka
- Graduate School of Technology, Department of Biotechnology, Tokyo University of Agriculture and Technology, 2-24-16 Naka-cho, Koganei, Tokyo 184-8588, Japan
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24
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Yuan X, Iijima M, Oishi M, Nagasaki Y. Structure and activity assay of nanozymes prepared by the coimmobilization of practically useful enzymes and hydrophilic block copolymers on gold nanoparticles. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2008; 24:6903-6909. [PMID: 18510375 DOI: 10.1021/la7039288] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Enzyme/polymer/gold nanoparticle hybrids, called "nanozymes", were prepared and structurally analyzed by dynamic light scattering (DLS), ultraviolet-visible spectroscopy, and zeta-potential and transmission electron microscopy (TEM) measurements, which showed that the nanozyme particles were mainly composed of a single gold nanoparticle, on whose surface the enzyme and polymer were coimmobilized. This kind of structure resulted in the high dispersion stability of the nanozyme under various conditions, accompanied by improved thermal stability of the enzyme.
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Affiliation(s)
- Xiaofei Yuan
- Graduate School of Pure and Applied Sciences, University of Tsukuba, 1-1-1 Ten-noudai, Tsukuba, Ibaraki 305-8753, Japan
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Sakaguchi-Mikami A, Taneoka A, Yamoto R, Ferri S, Sode K. Engineering of ligand specificity of periplasmic binding protein for glucose sensing. Biotechnol Lett 2008; 30:1453-60. [DOI: 10.1007/s10529-008-9712-7] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2008] [Revised: 03/11/2008] [Accepted: 03/13/2008] [Indexed: 10/22/2022]
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26
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A Promising Reconstitution Platform for PQQ-Dependent Apo-Enzymes in Chitosan–Carbon Nanotube Matrices. ACTA ACUST UNITED AC 2008. [DOI: 10.1149/1.2900014] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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27
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Study of the reactivity of quinohemoprotein alcohol dehydrogenase with heterocycle-pentacyanoferrate(III) complexes and the electron transfer path calculations. Open Life Sci 2007. [DOI: 10.2478/s11535-007-0033-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
AbstractThe reactivity of alcohol dehydrogenase IIG (ADH IIG) from Pseudomonas putida HK5 with new heterocycle-pentacyanoferrate(III) complexes and hexacyanoferrate(III) was determined at pH 7.2. The pentacyanoferrate(III) complexes contained imidazole, pyrazole, pyridine, their derivatives and 2-aminobenzothiazole as the sixth ligand. The largest reactivity of the complexes with ADH IIG was estimated for the complex containing pyridine. An apparent bimolecular constant (k
ox) for this complex was 8.7 × 105 M−1s−1. The lowest value of k
ox was estimated for the complex with benzotriazole (k
ox = 3.1 × 104 M−1s−1). The investigation of the hexacyanoferrate(III) enzymatic reduction rate at different ionic strength gave a single negative charge of reduced ADH IIG. Docking calculations revealed two binding sites of the complexes in ADH-IIG structure. The first one is located at the entrance to the PQQ pocket, and the second is at the site of cytochrome domain. The calculations of electron transfer (ET) path indicated that the most effective ET takes place from heme to the complex docked at the entrance to the PQQ pocket. This shortest path is constructed of amino acids Ser607 and Cys606.
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Ivnitski D, Atanassov P, Apblett C. Direct Bioelectrocatalysis of PQQ-Dependent Glucose Dehydrogenase. ELECTROANAL 2007. [DOI: 10.1002/elan.200703899] [Citation(s) in RCA: 73] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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29
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Lau C, Borgmann S, Maciejewska M, Ngounou B, Gründler P, Schuhmann W. Improved specificity of reagentless amperometric PQQ-sGDH glucose biosensors by using indirectly heated electrodes. Biosens Bioelectron 2007; 22:3014-20. [PMID: 17291745 DOI: 10.1016/j.bios.2006.12.033] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2006] [Revised: 12/21/2006] [Accepted: 12/21/2006] [Indexed: 11/18/2022]
Abstract
Indirectly heated electrodes operating in a non-isothermal mode have been used as transducers for reagentless glucose biosensors. Pyrroloquinoline quinone-dependent soluble glucose dehydrogenase (PQQ-sGDH) was entrapped on the electrode surface within a redox hydrogel layer. Localized polymer film precipitation was invoked by electrochemically modulating the pH-value in the diffusion zone in front of the electrode. The resulting decrease in solubility of an anodic electrodeposition paint (EDP) functionalized with Osmium complexes leads to precipitation of the redox hydrogel concomitantly entrapping the enzyme. The resulting sensor architecture enables a fast electron transfer between enzyme and electrode surface. The glucose sensor was operated at pre-defined temperatures using a multiple current-pulse mode allowing reproducible indirect heating of the sensor. The sensor characteristics such as the apparent Michaelis constants K(M)(app) and maximum currents I(max)(app) were determined at different temperatures for the main substrate glucose as well as a potential interfering co-substrate maltose. The limit of detection increased with higher temperatures for both substrates (0.020 mM for glucose, and 0.023 mM for maltose at 48 degrees C). The substrate specificity of PQQ-sGDH is highly temperature dependent. Therefore, a mathematical model based on a multiple linear regression approach could be applied to discriminate between the current response for glucose and maltose. This allowed accurate determination of glucose in a concentration range of 0-0.1mM in the presence of unknown maltose concentrations ranging from 0 to 0.04 mM.
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Affiliation(s)
- Carolin Lau
- Universität Rostock, Albert-Einsteinstrasse 3a, D-18051 Rostock, Germany
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In silico panning for a non-competitive peptide inhibitor. BMC Bioinformatics 2007; 8:11. [PMID: 17222344 PMCID: PMC1781467 DOI: 10.1186/1471-2105-8-11] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2006] [Accepted: 01/12/2007] [Indexed: 11/14/2022] Open
Abstract
Background Peptide ligands have tremendous therapeutic potential as efficacious drugs. Currently, more than 40 peptides are available in the market for a drug. However, since costly and time-consuming synthesis procedures represent a problem for high-throughput screening, novel procedures to reduce the time and labor involved in screening peptide ligands are required. We propose the novel approach of 'in silico panning' which consists of a two-stage screening, involving affinity selection by docking simulation and evolution of the peptide ligand using genetic algorithms (GAs). In silico panning was successfully applied to the selection of peptide inhibitor for water-soluble quinoprotein glucose dehydrogenase (PQQGDH). Results The evolution of peptide ligands for a target enzyme was achieved by combining a docking simulation with evolution of the peptide ligand using genetic algorithms (GAs), which mimic Darwinian evolution. Designation of the target area as next to the substrate-binding site of the enzyme in the docking simulation enabled the selection of a non-competitive inhibitor. In all, four rounds of selection were carried out on the computer; the distribution of the docking energy decreased gradually for each generation and improvements in the docking energy were observed over the four rounds of selection. One of the top three selected peptides with the lowest docking energy, 'SERG' showed an inhibitory effect with Ki value of 20 μM. PQQGDH activity, in terms of the Vmax value, was 3-fold lower than that of the wild-type enzyme in the presence of this peptide. The mechanism of the SERG blockage of the enzyme was identified as non-competitive inhibition. We confirmed the specific binding of the peptide, and its equilibrium dissociation constant (KD) value was calculated as 60 μM by surface plasmon resonance (SPR) analysis. Conclusion We demonstrate an effective methodology of in silico panning for the selection of a non-competitive peptide inhibitor from small virtual peptide library. This study is the first to demonstrate the usefulness of in silico evolution using experimental data. Our study highlights the usefulness of this strategy for structure-based screening of enzyme inhibitors.
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Kobayashi M, Kim J, Kobayashi N, Han S, Nakamura C, Ikebukuro K, Sode K. Pyrroloquinoline quinone (PQQ) prevents fibril formation of α-synuclein. Biochem Biophys Res Commun 2006; 349:1139-44. [PMID: 16962995 DOI: 10.1016/j.bbrc.2006.08.144] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2006] [Accepted: 08/25/2006] [Indexed: 11/24/2022]
Abstract
Pyrroloquinoline quinone (PQQ) is a noncovalently bound cofactor in the bacterial oxidative metabolism of alcohols. PQQ also exists in plants and animals. Due to its inherent chemical feature, namely its free-radical scavenging properties, PQQ has been drawing attention from both the nutritional and the pharmacological viewpoint. alpha-Synuclein, a causative factor of Parkinson's disease (PD), has the propensity to oligomerize and form fibrils, and this tendency may play a crucial role in its toxicity. We show that PQQ prevents the amyloid fibril formation and aggregation of alpha-synuclein in vitro in a PQQ-concentration-dependent manner. Moreover, PQQ forms a conjugate with alpha-synuclein, and this PQQ-conjugated alpha-synuclein is also able to prevent alpha-synuclein amyloid fibril formation. This is the first study to demonstrate the characteristics of PQQ as an anti-amyloid fibril-forming reagent. Agents that prevent the formation of amyloid fibrils might allow a novel therapeutic approach to PD. Therefore, together with further pharmacological approaches, PQQ is a candidate for future anti-PD reagent compounds.
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Affiliation(s)
- Masaki Kobayashi
- Department of Biotechnology, Graduate School of Engineering, Tokyo University of Agriculture and Technology, 184-8588 Tokyo, Koganei, Japan
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Hamamatsu N, Suzumura A, Nomiya Y, Sato M, Aita T, Nakajima M, Husimi Y, Shibanaka Y. Modified substrate specificity of pyrroloquinoline quinone glucose dehydrogenase by biased mutation assembling with optimized amino acid substitution. Appl Microbiol Biotechnol 2006; 73:607-17. [PMID: 16944137 DOI: 10.1007/s00253-006-0521-4] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2006] [Revised: 05/27/2006] [Accepted: 05/29/2006] [Indexed: 11/26/2022]
Abstract
A biased mutation-assembling method-that is, a directed evolution strategy to facilitate an optimal accumulation of multiple mutations on the basis of additivity principles, was applied to the directed evolution of water-soluble PQQ glucose dehydrogenase (PQQGDH-B) to reduce its maltose oxidation activity, which can lead to errors in blood glucose determination. Mutations appropriate for the reduction without fatal deterioration of its glucose oxidation activity were developed by an error-prone PCR method coupled with a saturation mutagenesis method. Moreover, two types of incorporation frequency based on their contribution were assigned to the mutations: high (80%) and evens (50%), in constructing a multiple mutant library. The best mutant created showed a marked reduction in maltose oxidation activity, corresponding to 4% of that of the wild-type enzyme, with 35% retention of glucose oxidation activity. In addition, this mutant showed a reduction in galactose oxidation activity corresponding to 5% of that of the wild-type enzyme. In conclusion, we succeeded in developing the PQQGDH-B mutants with improved substrate specificity and validated our method coupled with optimized mutations and their contribution-based incorporation frequencies by applying it to the development.
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Affiliation(s)
- Norio Hamamatsu
- Novartis Pharma K.K., Tsukuba Research Institute, Ohkubo 8, Tsukuba 300-2611, Japan
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OKUMURA N, ABO T, TSUJIMURA S, KANO K. Electron Transfer Kinetics between PQQ-dependent Soluble Glucose Dehydrogenase and Mediators. ELECTROCHEMISTRY 2006. [DOI: 10.5796/electrochemistry.74.639] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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Tanaka S, Igarashi S, Ferri S, Sode K. Increasing stability of water-soluble PQQ glucose dehydrogenase by increasing hydrophobic interaction at dimeric interface. BMC BIOCHEMISTRY 2005; 6:1. [PMID: 15715904 PMCID: PMC551599 DOI: 10.1186/1471-2091-6-1] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/13/2004] [Accepted: 02/16/2005] [Indexed: 11/26/2022]
Abstract
Background Water-soluble quinoprotein glucose dehydrogenase (PQQGDH-B) from Acinetobacter calcoaceticus has a great potential for application as a glucose sensor constituent. Because this enzyme shows no activity in its monomeric form, correct quaternary structure is essential for the formation of active enzyme. We have previously reported on the increasing of the stability of PQQGDH-B by preventing the subunit dissociation. Previous studies were based on decreasing the entropy of quaternary structure dissociation but not on increasing the interaction between the two subunits. We therefore attempted to introduce a hydrophobic interaction in the dimeric interface to increase the stability of PQQGDH-B. Results Amino acid residues Asn340 and Tyr418 face each other at the dimer interface of PQQGDH-B, however no interaction exists between their side chains. We simultaneously substituted Asn340 to Phe and Tyr418 to Phe or Ile, to create the two mutants Asn340Phe/Tyr418Phe and Asn340Phe/Tyr418Ile. Furthermore, residues Leu280, Val282 and Val342 form a hydrophobic region that faces, on the other subunit, residues Thr416 and Thr417, again without any specific interaction. We simultaneously substituted Thr416 and Thr417 to Val, to create the mutant Thr416Val/Thr417Val. The temperatures resulting in lose of half of the initial activity of the constructed mutants were increased by 3–4°C higher over wild type. All mutants showed 2-fold higher thermal stability at 55°C than the wild-type enzyme, without decreasing their catalytic activities. From the 3D models of all the mutant enzymes, the predicted binding energies were found to be significantly greater that in the wild-type enzyme, consistent with the increases in thermal stabilities. Conclusions We have achieved via site-directed mutagenesis the improvement of the thermal stability of PQQGDH-B by increasing the dimer interface interaction. Through rational design based on the quaternary structure of the enzyme, we selected residues located at the dimer interface that do not contribute to the intersubunit interaction. By substituting these residues to hydrophobic ones, the thermal stability of PQQGDH-B was increased without decreasing its catalytic activity.
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Affiliation(s)
- Shunsuke Tanaka
- Department of Biotechnology, Tokyo University of Agriculture and Technology, 2-24-13 Naka-machi, Koganei, Tokyo, 184-8588, Japan
| | - Satoshi Igarashi
- Department of Biotechnology, Tokyo University of Agriculture and Technology, 2-24-13 Naka-machi, Koganei, Tokyo, 184-8588, Japan
| | - Stefano Ferri
- Department of Biotechnology, Tokyo University of Agriculture and Technology, 2-24-13 Naka-machi, Koganei, Tokyo, 184-8588, Japan
| | - Koji Sode
- Department of Biotechnology, Tokyo University of Agriculture and Technology, 2-24-13 Naka-machi, Koganei, Tokyo, 184-8588, Japan
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Fitzpatrick P. Special issue on enzyme mechanisms. Arch Biochem Biophys 2005. [DOI: 10.1016/j.abb.2004.11.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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