1
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Bowling PE, Dasgupta S, Herbert JM. Eliminating Imaginary Vibrational Frequencies in Quantum-Chemical Cluster Models of Enzymatic Active Sites. J Chem Inf Model 2024; 64:3912-3922. [PMID: 38648614 DOI: 10.1021/acs.jcim.4c00221] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/25/2024]
Abstract
In constructing finite models of enzyme active sites for quantum-chemical calculations, atoms at the periphery of the model must be constrained to prevent unphysical rearrangements during geometry relaxation. A simple fixed-atom or "coordinate-lock" approach is commonly employed but leads to undesirable artifacts in the form of small imaginary frequencies. These preclude evaluation of finite-temperature free-energy corrections, limiting thermochemical calculations to enthalpies only. Full-dimensional vibrational frequency calculations are possible by replacing the fixed-atom constraints with harmonic confining potentials. Here, we compare that approach to an alternative strategy in which fixed-atom contributions to the Hessian are simply omitted. While the latter strategy does eliminate imaginary frequencies, it tends to underestimate both the zero-point energy and the vibrational entropy while introducing artificial rigidity. Harmonic confining potentials eliminate imaginary frequencies and provide a flexible means to construct active-site models that can be used in unconstrained geometry relaxations, affording better convergence of reaction energies and barrier heights with respect to the model size, as compared to models with fixed-atom constraints.
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Affiliation(s)
- Paige E Bowling
- Biophysics Graduate Program, The Ohio State University, Columbus, Ohio 43210, United States
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, Ohio 43210, United States
| | - Saswata Dasgupta
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, Ohio 43210, United States
- Department of Chemistry and Biochemistry, University of California-San Diego, La Jolla, California 92093, United States
| | - John M Herbert
- Biophysics Graduate Program, The Ohio State University, Columbus, Ohio 43210, United States
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, Ohio 43210, United States
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2
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Wappett D, Goerigk L. Benchmarking Density Functional Theory Methods for Metalloenzyme Reactions: The Introduction of the MME55 Set. J Chem Theory Comput 2023; 19:8365-8383. [PMID: 37943578 PMCID: PMC10688432 DOI: 10.1021/acs.jctc.3c00558] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2023] [Revised: 10/13/2023] [Accepted: 10/16/2023] [Indexed: 11/10/2023]
Abstract
We present a new benchmark set of metalloenzyme model reaction energies and barrier heights that we call MME55. The set contains 10 different enzymes, representing eight transition metals, both open and closed shell systems, and system sizes of up to 116 atoms. We use four DLPNO-CCSD(T)-based approaches to calculate reference values against which we then benchmark the performance of a range of density functional approximations with and without dispersion corrections. Dispersion corrections improve the results across the board, and triple-ζ basis sets provide the best balance of efficiency and accuracy. Jacob's ladder is reproduced for the whole set based on averaged mean absolute (percent) deviations, with the double hybrids SOS0-PBE0-2-D3(BJ) and revDOD-PBEP86-D4 standing out as the most accurate methods for the MME55 set. The range-separated hybrids ωB97M-V and ωB97X-V also perform well here and can be recommended as a reliable compromise between accuracy and efficiency; they have already been shown to be robust across many other types of chemical problems, as well. Despite the popularity of B3LYP in computational enzymology, it is not a strong performer on our benchmark set, and we discourage its use for enzyme energetics.
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Affiliation(s)
- Dominique
A. Wappett
- School of Chemistry, The University
of Melbourne, Melbourne, Victoria 3010, Australia
| | - Lars Goerigk
- School of Chemistry, The University
of Melbourne, Melbourne, Victoria 3010, Australia
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3
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Winiarska A, Ramírez-Amador F, Hege D, Gemmecker Y, Prinz S, Hochberg G, Heider J, Szaleniec M, Schuller JM. A bacterial tungsten-containing aldehyde oxidoreductase forms an enzymatic decorated protein nanowire. SCIENCE ADVANCES 2023; 9:eadg6689. [PMID: 37267359 PMCID: PMC10413684 DOI: 10.1126/sciadv.adg6689] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/13/2023] [Accepted: 04/28/2023] [Indexed: 06/04/2023]
Abstract
Aldehyde oxidoreductases (AORs) are tungsten enzymes catalyzing the oxidation of many different aldehydes to the corresponding carboxylic acids. In contrast to other known AORs, the enzyme from the denitrifying betaproteobacterium Aromatoleum aromaticum (AORAa) consists of three different subunits (AorABC) and uses nicotinamide adenine dinucleotide (NAD) as an electron acceptor. Here, we reveal that the enzyme forms filaments of repeating AorAB protomers that are capped by a single NAD-binding AorC subunit, based on solving its structure via cryo-electron microscopy. The polyferredoxin-like subunit AorA oligomerizes to an electron-conducting nanowire that is decorated with enzymatically active and W-cofactor (W-co) containing AorB subunits. Our structure further reveals the binding mode of the native substrate benzoate in the AorB active site. This, together with quantum mechanics:molecular mechanics (QM:MM)-based modeling for the coordination of the W-co, enables formulation of a hypothetical catalytic mechanism that paves the way to further engineering for applications in synthetic biology and biotechnology.
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Affiliation(s)
- Agnieszka Winiarska
- Jerzy Haber Institute of Catalysis and Surface Chemistry Polish Academy of Sciences, Kraków, Poland
| | - Fidel Ramírez-Amador
- SYNMIKRO Research Center and Department of Chemistry, Philipps-University of Marburg, Marburg, Germany
| | - Dominik Hege
- Faculty of Biology, Philipps-University of Marburg, Marburg, Germany
| | - Yvonne Gemmecker
- Faculty of Biology, Philipps-University of Marburg, Marburg, Germany
| | - Simone Prinz
- Max Planck Institute of Biophysics, Frankfurt am Main, Germany
| | - Georg Hochberg
- Max Planck Institute for Terrestrial Microbiology, Marburg, Germany
| | - Johann Heider
- SYNMIKRO Research Center and Department of Chemistry, Philipps-University of Marburg, Marburg, Germany
- Faculty of Biology, Philipps-University of Marburg, Marburg, Germany
| | - Maciej Szaleniec
- Jerzy Haber Institute of Catalysis and Surface Chemistry Polish Academy of Sciences, Kraków, Poland
| | - Jan Michael Schuller
- SYNMIKRO Research Center and Department of Chemistry, Philipps-University of Marburg, Marburg, Germany
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4
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Hagen WR. The Development of Tungsten Biochemistry-A Personal Recollection. Molecules 2023; 28:molecules28104017. [PMID: 37241758 DOI: 10.3390/molecules28104017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2023] [Revised: 04/27/2023] [Accepted: 05/08/2023] [Indexed: 05/28/2023] Open
Abstract
The development of tungsten biochemistry is sketched from the viewpoint of personal participation. Following its identification as a bio-element, a catalogue of genes, enzymes, and reactions was built up. EPR spectroscopic monitoring of redox states was, and remains, a prominent tool in attempts to understand tungstopterin-based catalysis. A paucity of pre-steady-state data remains a hindrance to overcome to this day. Tungstate transport systems have been characterized and found to be very specific for W over Mo. Additional selectivity is presented by the biosynthetic machinery for tungstopterin enzymes. Metallomics analysis of hyperthermophilic archaeon Pyrococcus furiosus indicates a comprehensive inventory of tungsten proteins.
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Affiliation(s)
- Wilfred R Hagen
- Department of Biotechnology, Delft University of Technology, Building 58, Van der Maasweg 9, 2629 HZ Delft, The Netherlands
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5
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Mathew LG, Haja DK, Pritchett C, McCormick W, Zeineddine R, Fontenot LS, Rivera ME, Glushka J, Adams MWW, Lanzilotta WN. An unprecedented function for a tungsten-containing oxidoreductase. J Biol Inorg Chem 2022; 27:747-758. [PMID: 36269456 DOI: 10.1007/s00775-022-01965-0] [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: 04/26/2022] [Accepted: 09/30/2022] [Indexed: 01/05/2023]
Abstract
Five tungstopterin-containing oxidoreductases were characterized from the hyperthermophile Pyrococcus furiosus. Each enzyme catalyzes the reversible conversion of one or more aldehydes to the corresponding carboxylic acid, but they have different specificities. The physiological functions of only two of these enzymes are known: one, termed GAPOR, is a glycolytic enzyme that oxidizes glyceraldehyde-3-phosphate, while the other, termed AOR, oxidizes multiple aldehydes generated during peptide fermentation. Two of the enzymes have known structures (AOR and FOR). Herein, we focus on WOR5, the fifth tungstopterin enzyme to be discovered in P. furiosus. Expression of WOR5 was previously shown to be increased during cold shock (growth at 72 ℃), although the physiological substrate is not known. To gain insight into WOR5 function, we sought to determine both its structure and identify its intracellular substrate. Crystallization experiments were performed with a concentrated cytoplasmic extract of P. furiosus grown at 72 ℃ and the structure of WOR5 was deduced from the crystals that were obtained. In contrast to a previous report, WOR5 is heterodimeric containing an additional polyferredoxin-like subunit with four [4Fe-4S] clusters. The active site structure of WOR5 is substantially different from that of AOR and FOR and the significant electron density observed adjacent to the tungsten cofactor of WOR5 was modeled as an aliphatic sulfonate. Biochemical assays and product analysis confirmed that WOR5 is an aliphatic sulfonate ferredoxin oxidoreductase (ASOR). A catalytic mechanism for ASOR is proposed based on the structural information and the potential role of ASOR in the cold-shock response is discussed.
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Affiliation(s)
- Liju G Mathew
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, GA, 30602, USA
| | - Dominik K Haja
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, GA, 30602, USA
| | - Clayton Pritchett
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, GA, 30602, USA
| | - Winston McCormick
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, GA, 30602, USA
| | - Robbie Zeineddine
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, GA, 30602, USA
| | - Leo S Fontenot
- Department of Chemistry, Louisiana State University, Baton Rouge, LA, 70803, USA
| | - Mario E Rivera
- Department of Chemistry, Louisiana State University, Baton Rouge, LA, 70803, USA
| | - John Glushka
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, GA, 30602, USA
| | - Michael W W Adams
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, GA, 30602, USA.
| | - William N Lanzilotta
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, GA, 30602, USA.
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6
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Zhang W, Bushnell EA. A QM/MM investigation of the catalytic mechanism of acetylene hydratase: insights into engineering a more effective enzyme. CAN J CHEM 2021. [DOI: 10.1139/cjc-2020-0322] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
In the present investigation, a QM/MM approach was used to better understand the effect of the second environmental shell of the active site on the catalytic conversion of acetylene to acetaldehyde by acetylene hydratase (AH). In addition, the effect of substituting W-coordinating sulfur atoms with selenium atoms was done to provide insight into the influence of the W-coordinating atoms on the catalytic reaction. From the results, it found that the presence of the second shell environment had a significant effect on the reaction. Specifically, in the absence of the MM second shell environment (i.e., QM-cluster model), the rate-determining step is defined by the first proton transfer step. In contrast, for the QM/MM model, the rate-determining step is defined by the water attacking step. Moreover, with the presence of the MM second shell environment, a key intermediate found in the DFT-cluster investigation does not exist in the QM/MM investigation. Rather, what was a two-step process in the DFT-cluster study was calculated to occur in a single step for the QM/MM study. Regarding the sulfur to selenium substitutions, it was found that Gibbs energy for the acetylene binding phase was significantly affected. Notably, the trans-position selenium made the binding of acetylene 65.6 kJ mol−1 less endergonic. Moreover, the overall reaction became 38.2 kJ mol−1 less endergonic compared with the wild type (WT) AH model. Thus, the substitution of key W-coordinating sulfur atoms with selenium atoms may offer a means to enhance the catalytic mechanism of AH considerably.
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Affiliation(s)
- Wenyuan Zhang
- Department of Chemistry, Brandon University, 270-18th Street, Brandon, MB R7A 6A9, Canada
- Department of Chemistry, Brandon University, 270-18th Street, Brandon, MB R7A 6A9, Canada
| | - Eric A.C. Bushnell
- Department of Chemistry, Brandon University, 270-18th Street, Brandon, MB R7A 6A9, Canada
- Department of Chemistry, Brandon University, 270-18th Street, Brandon, MB R7A 6A9, Canada
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7
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Hagedoorn PL. Steady-state kinetics of the tungsten containing aldehyde: ferredoxin oxidoreductases from the hyperthermophilic archaeon Pyrococcus furiosus. J Biotechnol 2019; 306:142-148. [PMID: 31589889 DOI: 10.1016/j.jbiotec.2019.10.005] [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: 08/02/2019] [Revised: 09/22/2019] [Accepted: 10/03/2019] [Indexed: 10/25/2022]
Abstract
The tungsten containing Aldehyde:ferredoxin oxidoreductases (AOR) offer interesting opportunities for biocatalytic approaches towards aldehyde oxidation and carboxylic acid reduction. The hyperthermophilic archaeon Pyrococcus furiosus encodes five different AOR family members: glyceraldehyde-3-phosphate oxidoreductase (GAPOR), aldehyde oxidoreductase (AOR), and formaldehyde oxidoreductase (FOR), WOR4 and WOR5. GAPOR functions as a glycolytic enzyme and is highly specific for the substrate glyceraldehyde-3-phosphate (GAP). AOR, FOR and WOR5 have a broad substrate spectrum, and for WOR4 no substrate has been identified to date. As ambiguous kinetic parameters have been reported for different AOR family enzymes the steady state kinetics under different physiologically relevant conditions was explored. The GAPOR substrate GAP was found to degrade at 60 °C by non-enzymatic elimination of the phosphate group to methylglyoxal with a half-life t1/2 = 6.5 min. Methylglyoxal is not a substrate or inhibitor of GAPOR. D-GAP was identified as the only substrate oxidized by GAPOR, and the kinetics of the enzyme was unaffected by the presence of L-GAP, which makes GAPOR the first enantioselective enzyme of the AOR family. The steady-state kinetics of GAPOR showed partial substrate inhibition, which assumes the GAP inhibited form of the enzyme retains some activity. This inhibition was found to be alleviated completely by a 1 M NaCl resulting in increased enzyme activity at high substrate concentrations. GAPOR activity was strongly pH dependent, with the optimum at pH 9. At pH 9, the substrate is a divalent anion and, therefore, positively charged amino acid residues are likely to be involved in the binding of the substrate. FOR exhibited a significant primary kinetic isotope effect of the apparent Vmax for the deuterated substrate, formaldehyde-d2, which shows that the rate-determining step involves a CH bond break from the aldehyde. The implications of these results for the reaction mechanism of tungsten-containing AORs, are discussed.
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Affiliation(s)
- Peter-Leon Hagedoorn
- Department of Biotechnology, Delft University of Technology, Van der Maasweg 9, 2629HZ, Delft, the Netherlands.
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8
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Sun SQ, Chen SL. How does Mo-dependent perchlorate reductase work in the decomposition of oxyanions? Dalton Trans 2019; 48:5683-5691. [DOI: 10.1039/c9dt00863b] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
The mechanisms of Mo-dependent perchlorate reductase (PcrAB)-catalyzed decomposition of perchlorate, bromate, iodate, and nitrate were revealed by density functional calculations.
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Affiliation(s)
- Shuo-Qi Sun
- Key Laboratory of Cluster Science of Ministry of Education
- School of Chemistry and Chemical Engineering
- Beijing Institute of Technology
- Beijing 100081
- China
| | - Shi-Lu Chen
- Key Laboratory of Cluster Science of Ministry of Education
- School of Chemistry and Chemical Engineering
- Beijing Institute of Technology
- Beijing 100081
- China
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9
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Wei WJ, Qian HX, Wang WJ, Liao RZ. Computational Understanding of the Selectivities in Metalloenzymes. Front Chem 2018; 6:638. [PMID: 30622942 PMCID: PMC6308299 DOI: 10.3389/fchem.2018.00638] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2018] [Accepted: 12/07/2018] [Indexed: 01/26/2023] Open
Abstract
Metalloenzymes catalyze many different types of biological reactions with high efficiency and remarkable selectivity. The quantum chemical cluster approach and the combined quantum mechanics/molecular mechanics methods have proven very successful in the elucidation of the reaction mechanism and rationalization of selectivities in enzymes. In this review, recent progress in the computational understanding of various selectivities including chemoselectivity, regioselectivity, and stereoselectivity, in metalloenzymes, is discussed.
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Affiliation(s)
| | | | | | - Rong-Zhen Liao
- Key Laboratory of Material Chemistry for Energy Conversion and Storage, Ministry of Education, Hubei Key Laboratory of Bioinorganic Chemistry and Materia Medica, Hubei Key Laboratory of Materials Chemistry and Service Failure, School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology, Wuhan, China
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10
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Qian HX, Liao RZ. QM/MM Study of Tungsten-Dependent Benzoyl-Coenzyme A Reductase: Rationalization of Regioselectivity and Predication of W vs Mo Selectivity. Inorg Chem 2018; 57:10667-10678. [DOI: 10.1021/acs.inorgchem.8b01328] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Hui-Xia Qian
- Key Laboratory of Material Chemistry for Energy Conversion and Storage, Ministry of Education, Hubei Key Laboratory of Bioinorganic Chemistry and Materia Medica, Hubei Key Laboratory of Materials Chemistry and Service Failure, School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology, Wuhan 430074, China
| | - Rong-Zhen Liao
- Key Laboratory of Material Chemistry for Energy Conversion and Storage, Ministry of Education, Hubei Key Laboratory of Bioinorganic Chemistry and Materia Medica, Hubei Key Laboratory of Materials Chemistry and Service Failure, School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology, Wuhan 430074, China
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11
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Fernández L, Pérez-Pla FF, Tuñón I, Llopis E. DFT Study on the Interaction of Tris(benzene-1,2-dithiolato)molybdenum Complex with Water. A Hydrolysis Mechanism Involving a Feasible Seven-Coordinate Aquomolybdenum Intermediate. J Phys Chem A 2016; 120:9636-9646. [PMID: 27933913 DOI: 10.1021/acs.jpca.6b10233] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
In the present work, the reactivity of the tris(benzene-1,2-dithiolato)molybdenum complex ([Mo(bdt)3]) toward water is studied by means of the density functional theory (DFT). DFT calculations were performed using the M06, B3P86, and B3PW91 hybrid functionals for comparison purposes. The M06 method was employed to elucidate the reaction pathway, relative stability of the intermediate products, nature of the Mo-S bond cleavage, and electronic structure of the involved molybdenum species. This functional was also used to study the transference of electrons from the molybdenum center toward the ligands. The reaction pathway confirms that [Mo(bdt)3] undergoes hydrolysis, yielding dihydroxo-bis(benzene-1,2-dithiolato)molybdenum complex ([Mo(OH)2(bdt)2]) and benzenedithiol. The reaction takes place through seven transition structures, one of them involving an aquo seven-coordinate molybdenum intermediate stabilized by a lone pair (LP) LPO→LPMo hyperconjugative interaction. This heptacoordinate species allows understanding of the observed oxygen atom exchange between water and tertiary phosphines mediated by these complexes. Calculations also show that [Mo(C2H4S2)3] and [Mo(OH)2(C2H4S2)2] have d2 and d0 electronic configuration, and hence an electron pair must be transferred during the course of the hydrolysis. The frontier molecular orbital (FMO) analysis concludes that the electron pair is transferred in the rupture of the second Mo-S bond, from the occupied donating Mo dx2-y2 orbital to the unoccupied C2H4(SH)2 S-C σ* ligand orbital. This result is supported by the bond dissociation energy calculations, which demonstrate that the neutral dissociation of the second Mo-S bond is energetically the more favorable.
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Affiliation(s)
- Lorenzo Fernández
- Institut de Cíencia dels Materials (ICMUV) , c/Catedrático Beltrán 2, 46980, Valencia, Spain
| | - Francisco F Pérez-Pla
- Institut de Cíencia dels Materials (ICMUV) , c/Catedrático Beltrán 2, 46980, Valencia, Spain
| | - Iñaki Tuñón
- Departamento de Química Física, Universitat de València , Dr. Moliner 50, 46100, Burjassot, Valencia, Spain
| | - Elisa Llopis
- Institut de Cíencia dels Materials (ICMUV) , c/Catedrático Beltrán 2, 46980, Valencia, Spain
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12
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Jafari S, Ryde U, Irani M. Catalytic mechanism of human glyoxalase I studied by quantum-mechanical cluster calculations. ACTA ACUST UNITED AC 2016. [DOI: 10.1016/j.molcatb.2016.05.010] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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13
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Cerqueira NMFSA, Pakhira B, Sarkar S. Theoretical studies on mechanisms of some Mo enzymes. J Biol Inorg Chem 2015; 20:323-35. [DOI: 10.1007/s00775-015-1237-7] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2014] [Accepted: 01/05/2015] [Indexed: 11/30/2022]
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14
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Xie H, Liu C, Chen X, Lei Q, Fang W, Zhou T. Theoretically exploring the key role of the Lys412 residue in the conversion of N2O to N2by nitrous oxide reductase from Achromobacter cycloclastes. NEW J CHEM 2015. [DOI: 10.1039/c5nj01339a] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
The active CuZcluster of NOR provides strong back-donation to coordinated N2O and activates the O atom of the N2O group facilitating H-bonding and protonationviathe Lys412 residue.
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Affiliation(s)
- Hujun Xie
- Department of Applied Chemistry
- Zhejiang Gongshang University
- Hangzhou 310018
- People's Republic of China
| | - Chengcheng Liu
- Department of Applied Chemistry
- Zhejiang Gongshang University
- Hangzhou 310018
- People's Republic of China
| | - Xuelin Chen
- Department of Applied Chemistry
- Zhejiang Gongshang University
- Hangzhou 310018
- People's Republic of China
| | - Qunfang Lei
- Department of Chemistry
- Zhejiang University
- Hangzhou 310027
- People's Republic of China
| | - Wenjun Fang
- Department of Chemistry
- Zhejiang University
- Hangzhou 310027
- People's Republic of China
| | - Tao Zhou
- Department of Applied Chemistry
- Zhejiang Gongshang University
- Hangzhou 310018
- People's Republic of China
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15
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Carbohydrate metabolism in Archaea: current insights into unusual enzymes and pathways and their regulation. Microbiol Mol Biol Rev 2014; 78:89-175. [PMID: 24600042 DOI: 10.1128/mmbr.00041-13] [Citation(s) in RCA: 200] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
The metabolism of Archaea, the third domain of life, resembles in its complexity those of Bacteria and lower Eukarya. However, this metabolic complexity in Archaea is accompanied by the absence of many "classical" pathways, particularly in central carbohydrate metabolism. Instead, Archaea are characterized by the presence of unique, modified variants of classical pathways such as the Embden-Meyerhof-Parnas (EMP) pathway and the Entner-Doudoroff (ED) pathway. The pentose phosphate pathway is only partly present (if at all), and pentose degradation also significantly differs from that known for bacterial model organisms. These modifications are accompanied by the invention of "new," unusual enzymes which cause fundamental consequences for the underlying regulatory principles, and classical allosteric regulation sites well established in Bacteria and Eukarya are lost. The aim of this review is to present the current understanding of central carbohydrate metabolic pathways and their regulation in Archaea. In order to give an overview of their complexity, pathway modifications are discussed with respect to unusual archaeal biocatalysts, their structural and mechanistic characteristics, and their regulatory properties in comparison to their classic counterparts from Bacteria and Eukarya. Furthermore, an overview focusing on hexose metabolic, i.e., glycolytic as well as gluconeogenic, pathways identified in archaeal model organisms is given. Their energy gain is discussed, and new insights into different levels of regulation that have been observed so far, including the transcript and protein levels (e.g., gene regulation, known transcription regulators, and posttranslational modification via reversible protein phosphorylation), are presented.
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16
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He R, Yang Q, Li M. Acylation and deacylation mechanism of Helicobacter pylori AmiF formamidase: A computational DFT study. Chem Phys Lett 2014. [DOI: 10.1016/j.cplett.2014.02.005] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
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17
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Blomberg MRA, Borowski T, Himo F, Liao RZ, Siegbahn PEM. Quantum chemical studies of mechanisms for metalloenzymes. Chem Rev 2014; 114:3601-58. [PMID: 24410477 DOI: 10.1021/cr400388t] [Citation(s) in RCA: 431] [Impact Index Per Article: 43.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Affiliation(s)
- Margareta R A Blomberg
- Department of Organic Chemistry, Arrhenius Laboratory, Stockholm University , SE-106 91 Stockholm, Sweden
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18
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Why is the molybdenum-substituted tungsten-dependent formaldehyde ferredoxin oxidoreductase not active? A quantum chemical study. J Biol Inorg Chem 2013; 18:175-181. [PMID: 23183892 DOI: 10.1007/s00775-012-0961-5] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2012] [Accepted: 11/13/2012] [Indexed: 01/12/2023]
Abstract
Formaldehyde ferredoxin oxidoreductase is a tungsten-dependent enzyme that catalyzes the oxidative degradation of formaldehyde to formic acid. The molybdenum ion can be incorporated into the active site to displace the tungsten ion, but is without activity. Density functional calculations have been employed to understand the incapacitation of the enzyme caused by molybdenum substitution. The calculations show that the enzyme with molybdenum (Mo-FOR) has higher redox potential than that with tungsten, which makes the formation of the Mo(VI)=O complex endothermic by 14 kcal/mol. Following our previously suggested mechanism for this enzyme, the formaldehyde substrate oxidation was also investigated for Mo-FOR using the same quantum-mechanics-only model, except for the displacement of tungsten by molybdenum. The calculations demonstrate that formaldehyde oxidation occurs via a sequential two-step mechanism. Similarly to the tungsten-catalyzed reaction, the Mo(VI)=O species performs the nucleophilic attack on the formaldehyde carbon, followed by proton transfer in concert with two-electron reduction of the metal center. The first step is rate-limiting, with a total barrier of 28.2 kcal/mol. The higher barrier is mainly due to the large energy penalty for the formation of the Mo(VI)=O species.
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Yang L, Liao RZ, Ding WJ, Liu K, Yu JG, Liu RZ. Why calcium inhibits magnesium-dependent enzyme phosphoserine phosphatase? A theoretical study. Theor Chem Acc 2012. [DOI: 10.1007/s00214-012-1275-y] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Sousa SF, Fernandes PA, Ramos MJ. Computational enzymatic catalysis – clarifying enzymatic mechanisms with the help of computers. Phys Chem Chem Phys 2012; 14:12431-41. [DOI: 10.1039/c2cp41180f] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
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