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Scarpellini M, Gätjens J, Martin OJ, Kampf JW, Sherman SE, Pecoraro VL. Modeling the resting state of oxalate oxidase and oxalate decarboxylase enzymes. Inorg Chem 2008; 47:3584-93. [PMID: 18399627 DOI: 10.1021/ic701953g] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
In view of the biological and commercial interest in models for Oxalate Decarboxylases (OxDC) and Oxalate Oxidases (OxOx), we have synthesized and characterized three new Mn (II) complexes ( 1- 3) employing N3O-donor amino-carboxylate ligands (TCMA, 1,4,7-triazacyclononane- N-acetic acid; K (i) Pr 2TCMA, potassium 1,4-diisopropyl-1,4,7-triazacyclononane- N-acetate; and KBPZG, potassium N,N-bis(3,5-dimethylpyrazolyl methyl)glycinate). These complexes were characterized by several techniques including X-ray crystallographic analysis, X-band electron paramagnetic resonance (EPR), electrospray ionization mass spectrometry (ESI-MS), and cyclic voltammetry. The crystal structures of 1 and 3 revealed that both form infinite polymeric chains of Mn (II) complexes linked by the pendant carboxylate arms of the TCMA (-) and the BPZG (-) ligands in a syn-antipattern. Complex 2 crystallizes as a mononuclear Mn (II) cation, six-coordinate in a distorted octahedral geometry. Although complexes 1 and 3 crystallize as polymeric chains, all compounds present the same N3O-donor set atoms around the metal center as observed in the crystallographically characterized OxDC and OxOx. Moreover, complex 2 also contains two water molecules coordinated to the Mn center as observed in the active site of OxDC and OxOx. ESI-MS spectrometry, combined with EPR, were useful techniques to establish that complexes 1- 3 are present as mononuclear Mn (II) species in solution. Finally, complexes 1- 3 are able to model the resting state active sites, with special attention focused on complex 2 which provides the first exact first coordination sphere ligand structural model for the resting states of both OxDC and OxOx.
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Affiliation(s)
- Marciela Scarpellini
- Willard H. Dow Laboratories, Department of Chemistry, University of Michigan, 930 North University, Ann Arbor, MI 48109, USA
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Just V, Burrell M, Bowater L, McRobbie I, Stevenson C, Lawson D, Bornemann S. The identity of the active site of oxalate decarboxylase and the importance of the stability of active-site lid conformations. Biochem J 2007; 407:397-406. [PMID: 17680775 PMCID: PMC2275070 DOI: 10.1042/bj20070708] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Oxalate decarboxylase (EC 4.1.1.2) catalyses the conversion of oxalate into carbon dioxide and formate. It requires manganese and, uniquely, dioxygen for catalysis. It forms a homohexamer and each subunit contains two similar, but distinct, manganese sites termed sites 1 and 2. There is kinetic evidence that only site 1 is catalytically active and that site 2 is purely structural. However, the kinetics of enzymes with mutations in site 2 are often ambiguous and all mutant kinetics have been interpreted without structural information. Nine new site-directed mutants have been generated and four mutant crystal structures have now been solved. Most mutants targeted (i) the flexibility (T165P), (ii) favoured conformation (S161A, S164A, D297A or H299A) or (iii) presence (Delta162-163 or Delta162-164) of a lid associated with site 1. The kinetics of these mutants were consistent with only site 1 being catalytically active. This was particularly striking with D297A and H299A because they disrupted hydrogen bonds between the lid and a neighbouring subunit only when in the open conformation and were distant from site 2. These observations also provided the first evidence that the flexibility and stability of lid conformations are important in catalysis. The deletion of the lid to mimic the plant oxalate oxidase led to a loss of decarboxylase activity, but only a slight elevation in the oxalate oxidase side reaction, implying other changes are required to afford a reaction specificity switch. The four mutant crystal structures (R92A, E162A, Delta162-163 and S161A) strongly support the hypothesis that site 2 is purely structural.
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Affiliation(s)
- Victoria J. Just
- Department of Biological Chemistry, John Innes Centre, Norwich Research Park, Norwich NR4 7UH, U.K
| | - Matthew R. Burrell
- Department of Biological Chemistry, John Innes Centre, Norwich Research Park, Norwich NR4 7UH, U.K
| | - Laura Bowater
- Department of Biological Chemistry, John Innes Centre, Norwich Research Park, Norwich NR4 7UH, U.K
| | - Iain McRobbie
- Department of Biological Chemistry, John Innes Centre, Norwich Research Park, Norwich NR4 7UH, U.K
| | - Clare E. M. Stevenson
- Department of Biological Chemistry, John Innes Centre, Norwich Research Park, Norwich NR4 7UH, U.K
| | - David M. Lawson
- Department of Biological Chemistry, John Innes Centre, Norwich Research Park, Norwich NR4 7UH, U.K
| | - Stephen Bornemann
- Department of Biological Chemistry, John Innes Centre, Norwich Research Park, Norwich NR4 7UH, U.K
- To whom correspondence should be addressed (email )
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Burrell MR, Just VJ, Bowater L, Fairhurst SA, Requena L, Lawson DM, Bornemann S. Oxalate Decarboxylase and Oxalate Oxidase Activities Can Be Interchanged with a Specificity Switch of up to 282 000 by Mutating an Active Site Lid,. Biochemistry 2007; 46:12327-36. [DOI: 10.1021/bi700947s] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Matthew R. Burrell
- Department of Biological Chemistry, John Innes Centre, Norwich Research Park, Norwich NR4 7UH, United Kingdom
| | - Victoria J. Just
- Department of Biological Chemistry, John Innes Centre, Norwich Research Park, Norwich NR4 7UH, United Kingdom
| | - Laura Bowater
- Department of Biological Chemistry, John Innes Centre, Norwich Research Park, Norwich NR4 7UH, United Kingdom
| | - Shirley A. Fairhurst
- Department of Biological Chemistry, John Innes Centre, Norwich Research Park, Norwich NR4 7UH, United Kingdom
| | - Laura Requena
- Department of Biological Chemistry, John Innes Centre, Norwich Research Park, Norwich NR4 7UH, United Kingdom
| | - David M. Lawson
- Department of Biological Chemistry, John Innes Centre, Norwich Research Park, Norwich NR4 7UH, United Kingdom
| | - Stephen Bornemann
- Department of Biological Chemistry, John Innes Centre, Norwich Research Park, Norwich NR4 7UH, United Kingdom
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Castiñeiras A, Balboa S, Carballo R, González-Pérez JM, Niclós-Gutiérrez J. Structural Evidences for the Oxidation of α-Hydroxycarboxilic Acids to Oxalate Assisted by Copper(II) Ions. Z Anorg Allg Chem 2007. [DOI: 10.1002/zaac.200600362] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Svedružić D, Liu Y, Reinhardt LA, Wroclawska E, Cleland WW, Richards NGJ. Investigating the roles of putative active site residues in the oxalate decarboxylase from Bacillus subtilis. Arch Biochem Biophys 2007; 464:36-47. [PMID: 17459326 PMCID: PMC2041844 DOI: 10.1016/j.abb.2007.03.016] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2007] [Revised: 03/11/2007] [Accepted: 03/16/2007] [Indexed: 12/17/2022]
Abstract
Oxalate decarboxylase (OxDC) catalyzes the conversion of oxalate into CO(2) and formate using a catalytic mechanism that remains poorly understood. The Bacillus subtilis enzyme is composed of two cupin domains, each of which contains Mn(II) coordinated by four conserved residues. We have measured heavy atom isotope effects for a series of Bacillus subtilis OxDC mutants in which Arg-92, Arg-270, Glu-162, and Glu-333 are conservatively substituted in an effort to define the functional roles of these residues. This strategy has the advantage that observed isotope effects report directly on OxDC molecules in which the active site manganese center(s) is (are) catalytically active. Our results support the proposal that the N-terminal Mn-binding site can mediate catalysis, and confirm the importance of Arg-92 in catalytic activity. On the other hand, substitution of Arg-270 and Glu-333 affects both Mn(II) incorporation and the ability of Mn to bind to the OxDC mutants, thereby precluding any definitive assessment of whether the metal center in the C-terminal domain can also mediate catalysis. New evidence for the importance of Glu-162 in controlling metal reactivity has been provided by the unexpected observation that the E162Q OxDC mutant exhibits a significantly increased oxalate oxidase and a concomitant reduction in decarboxylase activities relative to wild type OxDC. Hence the reaction specificity of a catalytically active Mn center in OxDC can be perturbed by relatively small changes in local protein environment, in agreement with a proposal based on prior computational studies.
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Affiliation(s)
| | | | | | | | | | - Nigel G. J. Richards
- *Correspondence to Department of Chemistry, Box 117200, University of Florida, Gainesville, Fl 32611-7200, 352-392-3601 (Office); 352-392-7918 (Fax),
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Pan HY, Whittaker MM, Bouveret R, Berna A, Bernier F, Whittaker JW. Characterization of wheat germin (oxalate oxidase) expressed by Pichia pastoris. Biochem Biophys Res Commun 2007; 356:925-9. [PMID: 17399681 PMCID: PMC1987392 DOI: 10.1016/j.bbrc.2007.03.097] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2007] [Accepted: 03/12/2007] [Indexed: 01/08/2023]
Abstract
High-level secretory expression of wheat (Triticum aestivum) germin/oxalate oxidase was achieved in Pichia pastoris fermentation cultures as an alpha-mating factor signal peptide fusion, based on the native wheat cDNA coding sequence. The oxalate oxidase activity of the recombinant enzyme is substantially increased (7-fold) by treatment with sodium periodate, followed by ascorbate reduction. Using these methods, approximately 1 g (4x10(4) U) of purified, activated enzyme was obtained following eight days of induction of a high density Pichia fermentation culture, demonstrating suitability for large-scale production of oxalate oxidase for biotechnological applications. Characterization of the recombinant protein shows that it is glycosylated, with N-linked glycan attached at Asn47. For potential biomedical applications, a nonglycosylated (S49A) variant was also prepared which retains essentially full enzyme activity, but exhibits altered protein-protein interactions.
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Affiliation(s)
- Heng-Yen Pan
- Department of Environmental and Biomolecular Systems, Oregon Health and Sciences University, Beaverton, Oregon, 97006-8921
| | - Mei M. Whittaker
- Department of Environmental and Biomolecular Systems, Oregon Health and Sciences University, Beaverton, Oregon, 97006-8921
| | | | - Anne Berna
- IBMP-Institut de Botanique, Strasbourg, France
| | | | - James W. Whittaker
- Department of Environmental and Biomolecular Systems, Oregon Health and Sciences University, Beaverton, Oregon, 97006-8921
- * Address correspondence to: James W. Whittaker, Department of Environmental and Biomolecular Systems, Oregon Health and Science University, 20000 N.W. Walker Road, Beaverton, Oregon 97006-8921, Tel. 503 748-1065; Fax. 503 748-1464; E-Mail:
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Whittaker MM, Pan HY, Yukl ET, Whittaker JW. Burst Kinetics and Redox Transformations of the Active Site Manganese Ion in Oxalate Oxidase. J Biol Chem 2007; 282:7011-23. [PMID: 17210574 DOI: 10.1074/jbc.m609374200] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Oxalate oxidase (EC 1.2.3.4) catalyzes the oxidative cleavage of oxalate to carbon dioxide and hydrogen peroxide. In this study, unusual nonstoichiometric burst kinetics of the steady state reaction were observed and analyzed in detail, revealing that a reversible inactivation process occurs during turnover, associated with a slow isomerization of the substrate complex. We have investigated the underlying molecular mechanism of this kinetic behavior by preparing recombinant barley oxalate oxidase in three distinct oxidation states (Mn(II), Mn(III), and Mn(IV)) and producing a nonglycosylated variant for detailed biochemical and spectroscopic characterization. Surprisingly, the fully reduced Mn(II) form, which represents the majority of the as-isolated native enzyme, lacks oxalate oxidase activity, but the activity is restored by oxidation of the metal center to either Mn(III) or Mn(IV) forms. All three oxidation states appear to interconvert under turnover conditions, and the steady state activity of the enzyme is determined by a balance between activation and inactivation processes. In O(2)-saturated buffer, a turnover-based redox modification of the enzyme forms a novel superoxidized mononuclear Mn(IV) biological complex. An oxalate activation role for the catalytic metal ion is proposed based on these results.
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Affiliation(s)
- Mei M Whittaker
- Department of Environmental and Biomolecular Systems, Oregon Health and Sciences University, Beaverton, Oregon 97006-8921, USA
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Sabater L, Hureau C, Blain G, Guillot R, Thuéry P, Rivière E, Aukauloo A. Chemical and Electrochemical Behaviours of a New Phenolato-Bridged Complex [(L)MnIIMnII(L)]2+. Pathways to Mononuclear Chlorido [(L)MnII/III/IVCl]0/1/2+ and Dinuclear Mono-µ-Oxido [(L)MnIII(µ-O)MnIII/IV(L)]2+/3+ Species. Eur J Inorg Chem 2006. [DOI: 10.1002/ejic.200600274] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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