Wolfgang Lubitz

Max Planck Institute for Chemical Energy Conversion, Mülheim-on-Ruhr, North Rhine-Westphalia, Germany

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Publications (440)2144.84 Total impact

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    ABSTRACT: Direct spectroscopic evidence for a hydride bridge in the Ni–R form of [NiFe] hydrogenase has been obtained using iron-specific nuclear resonance vibrational spectroscopy (NRVS). The Ni–H–Fe wag mode at 675 cm −1 is the first spectroscopic evidence for a bridging hydride in Ni–R as well as the first iron-hydride-related NRVS feature observed for a biological system. Although density function theory (DFT) calculation assisted the determination of the Ni–R structure, it did not predict the Ni–H–Fe wag mode at ∼675 cm −1 before NRVS. Instead, the observed Ni–H–Fe mode provided a critical reference for the DFT calculations. While the overall science about Ni–R is presented and discussed elsewhere, this article focuses on the long and strenuous experimental journey to search for and experimentally identify the Ni–H–Fe wag mode in a Ni–R sample. As a methodology, the results presented here will go beyond Ni–R and hydrogenase research and will also be of interest to other scientists who use synchrotron radiation for measuring dilute samples or weak spectroscopic features.
    Journal of Synchrotron Radiation 11/2015; 22(Pt 6):1334-1344. DOI:10.1107/S1600577515017816 · 2.74 Impact Factor
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    ABSTRACT: A new class of synthetic models for the active site of [NiFe]-hydrogenases are described. The Ni(I/II)(SCys)2 and Fe(II)(CN)2CO sites are represented with (RC5H4)Ni(I/II) and Fe(II)(diphos)(CO) modules, where diphos = 1,2-C2H4(PPh2)2(dppe) or cis-1,2-C2H2(PPh2)2(dppv). The two bridging thiolate ligands are represented by CH2(CH2S)2(2-) (pdt(2-)), Me2C(CH2S)2(2-) (Me2pdt(2-)), and (C6H5S)2(2-). The reaction of Fe(pdt)(CO)2(dppe) and [(C5H5)3Ni2]BF4 affords [(C5H5)Ni(pdt)Fe(dppe)(CO)]BF4 ([1a]BF4). Monocarbonyl [1a]BF4 features an S = 0 Ni(II)Fe(II) center with five-coordinated iron, as proposed for the Ni-SIa state of the enzyme. One-electron reduction of [1a](+) affords the S = (1)/2 derivative [1a](0), which, according to density functional theory (DFT) calculations and electron paramagnetic resonance and Mössbauer spectroscopies, is best described as a Ni(I)Fe(II) compound. The Ni(I)Fe(II) assignment matches that for the Ni-L state in [NiFe]-hydrogenase, unlike recently reported Ni(II)Fe(I)-based models. Compound [1a](0) reacts with strong acids to liberate 0.5 equiv of H2 and regenerate [1a](+), indicating that H2 evolution is catalyzed by [1a](0). DFT calculations were used to investigate the pathway for H2 evolution and revealed that the mechanism can proceed through two isomers of [1a](0) that differ in the stereochemistry of the Fe(dppe)CO center. Calculations suggest that protonation of [1a](0) (both isomers) affords Ni(III)-H-Fe(II) intermediates, which represent mimics of the Ni-C state of the enzyme.
    Inorganic Chemistry 09/2015; DOI:10.1021/acs.inorgchem.5b01662 · 4.76 Impact Factor
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    ABSTRACT: The active site of [FeFe] hydrogenase contains a catalytic binuclear iron sub-site coordinated by CN(-) and CO ligands as well as a unique azadithiolate (adt(2-)) bridging ligand. It has been established that this binuclear cofactor is synthesized and assembled by three maturation proteins HydE,F,G. Using in vitro maturation in the presence of (15)N and (13)C labeled tyrosine it has been shown that the CN(-) and CO ligands originate from tyrosine. The source of the bridging adt(2-) ligand, however, remains as yet unknown. In order to identify the nitrogen of the bridging amine using HYSCORE spectroscopy and distinguish its spectroscopic signature from that of the CN(-) nitrogens we studied three isotope labeled variants of the H-cluster ((15)N-adt(2-)/C(14)N(-), (15)N-adt(2-)/C(15)N(-), and (14)N-adt(2-)/C(15)N(-)) and extracted accurate values of the hyperfine and quadrupole couplings of both CN(-) and adt(2-) nitrogens. This will allow to evaluate isotopologues of the H-cluster generated by in vitro bioassembly in the presence of various (15)N labeled potential precursors as possible sources of the bridging ligand.
    Journal of the American Chemical Society 09/2015; 137(40). DOI:10.1021/jacs.5b06240 · 12.11 Impact Factor
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    ABSTRACT: The metabolism of many anaerobes relies on [NiFe]-hydrogenases, whose characterization when bound to substrates has proven non-trivial. Presented here is direct evidence for a hydride bridge in the active site of the 57 Fe-labelled fully reduced Ni-R form of Desulfovibrio vulgaris Miyazaki F [NiFe]-hydrogenase. A unique ' wagging' mode involving H- motion perpendicular to the Ni(μ1/4-H)57 Fe plane was studied using 57 Fe-specific nuclear resonance vibrational spectroscopy and density functional theory (DFT) calculations. On Ni(μ1/4-D) 57 Fe deuteride substitution, this wagging causes a characteristic perturbation of Fe-CO/CN bands. Spectra have been interpreted by comparison with Ni(μ1/4-H/D) 57 Fe enzyme mimics [(dppe)Ni(μ1/4-pdt)(μ1/4-H/D) 57 Fe(CO)3 ]+ and DFT calculations, which collectively indicate a low-spin Ni(II)(μ1/4-H)Fe(II) core for Ni-R, with H- binding Ni more tightly than Fe. The present methodology is also relevant to characterizing Fe-H moieties in other important natural and synthetic catalysts.
    Nature Communications 08/2015; 6. DOI:10.1038/ncomms8890 · 11.47 Impact Factor
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    ABSTRACT: Das aktive Zentrum von Hydrogenasen inspiriert die Entwicklung molekularer Katalysatoren zur Wasserstoffumsetzung. Ein direkter Vergleich zwischen diesen Katalysatoren und dem Enzym war jedoch bisher nicht möglich, weil verschiedene Techniken zur Bewertung der Katalysatoreigenschaften verwendet wurden. Dies macht es schwierig zu beurteilen, inwieweit die synthetisierten Katalysatoren in ihrer Leistung an das Enzym heranreichen. Hier vergleichen wir die katalytischen Eigenschaften von Ni[(PCy2NGly2)2]+2 mit denen der [NiFe]-Hydrogenase aus Desulfovibrio vulgaris. Beide wurden auf funktionalisierten Elektroden unter identischen Bedingungen immobilisiert. Das Enzym zeigt bei pH 7 eine höhere Aktivität, geringere Überspannung und eine bessere Stabilität, während bei niedrigem pH-Wert der molekulare Katalysator das Enzym in jeder Hinsicht übertrifft. Dieser erste direkte Vergleich gibt Auskunft über die Vor- und Nachteile der beiden Systeme und Hinweise auf eine mögliche Verwendung bioinspirierter Komplexe in Brennstoffzellen.
    Angewandte Chemie 07/2015; DOI:10.1002/ange.201502364
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    ABSTRACT: The active site of hydrogenases has been a source of inspiration for the development of molecular catalysts. However, direct comparisons between molecular catalysts and enzymes have not been possible because different techniques are used to evaluate both types of catalysts, minimizing our ability to determine how far we have come in mimicking the enzymatic performance. The catalytic properties of the [Ni(P(Cy) 2 N(Gly) 2 )2 ](2+) complex with the [NiFe]-hydrogenase from Desulfovibrio vulgaris immobilized on a functionalized electrode were compared under identical conditions. At pH 7, the enzyme shows higher activity and lower overpotential with better stability, while at low pH, the molecular catalyst outperforms the enzyme in all respects. This is the first direct comparison of enzymes and molecular complexes, enabling a unique understanding of the benefits and detriments of both systems, and advancing our understanding of the utilization of these bio-inspired complexes in fuel cells. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
    Angewandte Chemie International Edition 07/2015; 54(42). DOI:10.1002/anie.201502364 · 11.26 Impact Factor
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    ABSTRACT: Diamagnetic iron chloro compounds [(P(Ph)2N(Ph)2)FeCp*Cl] [1Cl] and [(P(Cy)2N(Ph)2)FeCp*Cl] [2Cl] and the corresponding hydrido complexes [(P(Ph2)N(Ph2))FeCp*H] [1H] and [(P(Cy)2N(Ph)2)FeCp*H] [2H] have been synthesized and characterized by NMR spectroscopy, electrochemical studies, electronic absorption, and (57)Fe Mössbauer spectroscopy (P(Ph)2N(Ph)2 = 1,3,5,7-tetraphenyl-1,5-diphospha-3,7-diazacyclooctane, P(Cy2)N(Ph2) = 1,5-dicyclohexyl-3,7-diphenyl-1,5-diphospha-3,7-diazacyclooctane, Cp* = pentamethylcyclopentadienyl). Molecular structures of [2Cl], [1H], and [2H], derived from single-crystal X-ray diffraction, revealed that these compounds have a typical piano-stool geometry. The results show that the electronic properties of the hydrido complexes are strongly influenced by the substituents at the phosphorus donor atoms of the P(R)2N(Ph)2 ligand, whereas those of the chloro complexes are less affected. These results illustrate that the hydride is a strong-field ligand, as compared to chloride, and thus leads to a significant degree of covalent character of the iron hydride bonds. This is important in the context of possible catalytic intermediates of iron hydrido species, as proposed for the catalytic cycle of [FeFe] hydrogenases and other synthetic catalysts. Both hydrido compounds [1H] and [2H] show enhanced catalytic currents in cyclic voltammetry upon addition of the strong acid trifluoromethanesulfonimide [NHTf2] (pKa(MeCN) = 1.0). In contrast to the related complex [(P(tBu)N(Bn))2FeCp(C6F5)H], which was reported by Liu et al. (Nat. Chem. 2013, 5, 228-233) to be an electrocatalyst for hydrogen splitting, the here presented hydride complexes [1H] and [2H] show the tendency for electrocatalytic hydrogen production. Hence, the catalytic direction of this class of monoiron compounds can be reversed by specific ligand modifications.
    Inorganic Chemistry 07/2015; 54(14). DOI:10.1021/acs.inorgchem.5b00911 · 4.76 Impact Factor
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    ABSTRACT: The preparation and spectroscopic characterization of a fully active [FeFe] hydrogenase with a selectively 57Fe-labeled binuclear subsite is described. The precursor [57Fe2(adt)(CN)2(CO)4]2- was synthesized from the 57Fe metal, S8, CO, [Et4N]CN, NH4Cl, and OCH2. (Et4N)2[57Fe2(adt)(CN)2(CO)4] was then used for the maturation of the [FeFe] hydrogenase HydA1 from Chlamydomonas reinhardtii, to yield the enzyme selectively labeled at the [2Fe]H subcluster. Complementary 57Fe enrichment of the [4Fe-4S]H cluster was realized by reconstitution with 57FeCl3 and Na2S. The Hox-CO state of [257Fe]H and [457Fe-4S]H HydA1 was characterized by Mössbauer, HYSCORE, ENDOR, and nuclear resonance vibrational spectroscopy.
    Journal of the American Chemical Society 06/2015; 137(28). DOI:10.1021/jacs.5b03270 · 12.11 Impact Factor
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    ABSTRACT: Die Integration empfindlicher Katalysatoren in Redoxpolymere ist eine Möglichkeit, diese vor desaktivierenden Molekülen wie O2 zu schützen. [FeFe]-Hydrogenasen sind Enzyme, die die Oxidation sowie Produktion von H2 katalysieren. Da sie aber durch O2 irreversibel desaktiviert werden, war die Verwendung dieser Enzyme unter aeroben Bedingungen bisher unmöglich. Die Integration solcher Hydrogenasen in mit Viologenderivaten modifizierten Hydrogelfilmen ermöglicht auch in Gegenwart von O2 katalytische Ströme für die H2-Oxidation und demonstriert damit einen Schutzmechanismus unabhängig von Reaktivierungsprozessen. Im Hydrogel werden die Elektronen aus der durch die Hydrogenase katalysierten H2-Oxidation zur Hydrogel-Elektrolyt-Grenzfläche transportiert, um dort die schädlichen O2-Moleküle abzufangen, bevor sie die Hydrogenase desaktivieren können. Wir illustrieren mögliche Anwendungen dieses Schutzmechanismus für eine Biobrennstoffzelle bei gemischter H2/O2-Zufuhr.
    Angewandte Chemie 06/2015; DOI:10.1002/ange.201502776
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    ABSTRACT: The integration of sensitive catalysts in redox matrices opens up the possibility for their protection from deactivating molecules such as O2 . [FeFe]-hydrogenases are enzymes catalyzing H2 oxidation/production which are irreversibly deactivated by O2 . Therefore, their use under aerobic conditions has never been achieved. Integration of such hydrogenases in viologen-modified hydrogel films allows the enzyme to maintain catalytic current for H2 oxidation in the presence of O2 , demonstrating a protection mechanism independent of reactivation processes. Within the hydrogel, electrons from the hydrogenase-catalyzed H2 oxidation are shuttled to the hydrogel-solution interface for O2 reduction. Hence, the harmful O2 molecules do not reach the hydrogenase. We illustrate the potential applications of this protection concept with a biofuel cell under H2 /O2 mixed feed. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
    Angewandte Chemie International Edition 06/2015; 54(42):n/a-n/a. DOI:10.1002/anie.201502776 · 11.26 Impact Factor
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    ABSTRACT: The two resting forms of the active site of [NiFe] hydrogenase, Ni-A and Ni-B, have significantly different activation kinetics, but reveal nearly identical spectroscopic features which suggest the two states exhibit subtle structural differences. Previous studies have indicated that the states differ by the identity of the bridging ligand between Ni and Fe; proposals include OH-, OOH-, H2O, O2-, accompanied by modified cysteine residues. In this study, we use single crystal ENDOR spectroscopy and quantum chemical calculations within the framework of density functional theory (DFT) to calculate vibrational frequencies, 1H and 17O hyperfine coupling constants and g values with the aim to compare these data to experimental results obtained by crystallography, FTIR and EPR/ENDOR spectroscopy. We find that the Ni-A and Ni-B states are constitutional isomers that differ in their fine structural details. Calculated vibrational frequencies for the cyano and carbonyl ligands and 1H and 17O hyperfine coupling constants indicate that the bridging ligand in both Ni-A and Ni-B is indeed an OH- ligand. The difference in the isotropic hyperfine coupling constants of the β-CH2 protons of Cys-549 is sensitive to the orientation of Cys-549; a difference of 0.5 MHz is observed experimentally for Ni-A and 1.9 MHz for Ni-B, which results from a rotation of 7 degrees about the Cα-Cβ-Sγ-Ni dihedral angle. Likewise, the difference of the intermediate g value is correlated with a rotation of Cys-546 of about 10 degrees.
    Physical Chemistry Chemical Physics 05/2015; 17(24). DOI:10.1039/C5CP01322D · 4.49 Impact Factor
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    ABSTRACT: The regulatory hydrogenase (RH) from Ralstonia eutropha H16 acts as a sensor for the detection of environmental H2 and regulates gene expression related to hydrogenase-mediated cellular metabolism. In marked contrast to prototypical energy-converting [NiFe] hydrogenases, the RH is apparently insensitive to inhibition by O2 and CO. While the physiological function of regulatory hydrogenases is well established, little is known about the redox cycling of the [NiFe] center and the nature of the iron–sulfur (FeS) clusters acting as electron relay. The absence of any FeS cluster signals in EPR had been attributed to their particular nature, whereas the observation of essentially only two active site redox states, namely Ni-SI and Ni-C, invoked a different operant mechanism. In the present work, we employ a combination of Mössbauer, FTIR and EPR spectroscopic techniques to study the RH, and the results are consistent with the presence of three [4Fe–4S] centers in the small subunit. In the as-isolated, oxidized RH all FeS clusters reside in the EPR-silent 2+ state. Incubation with H2 leads to reduction of two of the [4Fe–4S] clusters, whereas only strongly reducing agents lead to reduction of the third cluster, which is ascribed to be the [4Fe–4S] center in ‘proximal’ position to the [NiFe] center. In the two different active site redox states, the low-spin FeII exhibits distinct Mössbauer features attributed to changes in the electronic and geometric structure of the catalytic center. The results are discussed with regard to the spectral characteristics and physiological function of H2-sensing regulatory hydrogenases.
    Chemical Science 05/2015; 6(8):4495-4507. DOI:10.1039/C5SC01560J · 9.21 Impact Factor
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    ABSTRACT: The transfer of photosynthetic electrons by the ferredoxin PetF to the [FeFe] hydrogenase HydA1 in the microalga Chlamydomonas reinhardtii is a key step in hydrogen production. Electron delivery requires a specific interaction between PetF and HydA1. However, due to the transient nature of the corresponding electron-transfer complex, an X-ray-structure remains elusive. Therefore, we performed protein-protein docking based on new experimental data from solution NMR spectroscopy on native and Gallium-substituted PetF that provides valuable information about residues crucial for complex formation and electron transfer. The derived complex model may help pinpoint residue substitution targets for improved hydrogen production. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
    ChemBioChem 05/2015; 16(11). DOI:10.1002/cbic.201500130 · 3.09 Impact Factor
  • Nicholas Cox · Dimitrios A Pantazis · Frank Neese · Wolfgang Lubitz ·
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    ABSTRACT: In the context of a global artificial photosynthesis (GAP) project, we review our current work on nature's water splitting catalyst. In a recent report (Cox et al. 2014 Science 345, 804-808 (doi:10.1126/science.1254910)), we showed that the catalyst-a Mn4O5Ca cofactor-converts into an 'activated' form immediately prior to the O-O bond formation step. This activated state, which represents an all Mn(IV) complex, is similar to the structure observed by X-ray crystallography but requires the coordination of an additional water molecule. Such a structure locates two oxygens, both derived from water, in close proximity, which probably come together to form the product O2 molecule. We speculate that formation of the activated catalyst state requires inherent structural flexibility. These features represent new design criteria for the development of biomimetic and bioinspired model systems for water splitting catalysts using first-row transition metals with the aim of delivering globally deployable artificial photosynthesis technologies.
    Interface focus: a theme supplement of Journal of the Royal Society interface 04/2015; 5(3):20150009-20150009. DOI:10.1098/rsfs.2015.0009 · 2.63 Impact Factor
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    ABSTRACT: The use of synthetic inorganic complexes as supported catalysts is a key route in energy production and in industrial synthesis. However, their intrinsic oxygen sensitivity is sometimes an issue. Some of us have recently demonstrated that hydrogenases, the fragile but very efficient biological catalysts of H2 oxidation, can be protected from O2 damage upon integration into a film of a specifically designed redox polymer. Catalytic oxidation of H2 produces electrons which reduce oxygen near the film/solution interface, thus providing a self-activated protection from oxygen [Plumeré et al., Nature Chemistry, 6, 822-827 (2014)]. Here, we rationalize this protection mechanism by examining the time-dependent distribution of species in the hydrogenase / polymer film, using measured or estimated values of all relevant parameters and the numerical and analytical solutions of a realistic reaction-diffusion scheme. Our investigation sets the stage for optimizing the design of hydrogenase-polymer films, and for expanding this strategy to other fragile catalysts.
    Journal of the American Chemical Society 04/2015; 137(16). DOI:10.1021/jacs.5b01194 · 12.11 Impact Factor
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    ABSTRACT: Nitrite is an important metabolite in the physiological pathways of NO and other nitrogen oxides in both enzymatic and non-enzymatic reactions. The ferric heme b protein nitrophorin 4 (NP4) is capable of catalyzing nitrite disproportionation at neutral pH, producing NO. Here we attempt to resolve its disproportionation mechanism. Isothermal titration calorimetry of a gallium(III) derivative of NP4 demonstrates that the heme iron coordinates the first substrate nitrite. Contrary to previous low temperature EPR measurements, which assigned the NP4-nitrite complex electronic configuration solely to a low-spin (S =1/2) species, electronic absorption, resonance Raman and (1)H-NMR spectroscopy presented here demonstrate that the NP4-NO2(-) cofactor exists in a high-spin/low-spin equilibrium of 7:3 which is in fast exchange in solution. Spin state interchange is taken as evidence for dynamic NO2(-) coordination, with the high-spin configuration (S = 5/2) representing the reactive species. Subsequent kinetic measurements reveal that the dismutation reaction proceeds in two discrete steps and identify an {FeNO}(7) intermediate species. The first reaction step, generating the {FeNO}(7) intermediate, represents an oxygen atom transfer from the iron bound nitrite to a second nitrite molecule in the protein pocket. In the second step this intermediate reduces a third nitrite substrate yielding two NO molecules. A nearby aspartic acid residue side-chain transiently stores protons required for the reaction, which is crucial for NPs' function as nitrite dismutase.
    Journal of the American Chemical Society 03/2015; 137(12). DOI:10.1021/ja512938u · 12.11 Impact Factor
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    ABSTRACT: The symmetry of the arrangement of objects has fascinated philosophers, artists and scientists for a long time, and still does. Symmetries often exist in Nature, but is also created artificially, for instance by chemical synthesis of novel molecules and materials. The one-sided, non-orientable Möbius band topology is a paradigm of such a symmetry-based fascination. In the early 1960’s, in synthetic organic chemistry the interest in molecules with Möbius symmetry was greatly stimulated by a short paper by Edgar Heilbronner. He predicted that sufficiently large [n]annulenes with a closed-shell electron configuration of 4n π-electrons should allow for sufficient π-overlap stabilization to be synthesizable by twisting them with a 180◦ phase change into the Möbius symmetry of their hydrocarbon skeleton. In 2007, the group of Lechosław Latos-Grażyński succeeded in synthesizing the compound di-p-benzi[28]hexa-phyrin(, compound 1, which can dynamically switch between Hückel and Möbius conjugation depending, in a complex manner, on the polarity and temperature of the surrounding solvent. This discovery of “topology switching” between the two-sided (Hückel) and one-sided (Möbius) molecular state with closed-shell electronic configuration was based primarily on the results of NMR spectroscopy and DFT calculations. The present EPR and ENDOR work on the radical cation state of compound 1 is the first study of a ground-state open-shell system which exhibits a Hückel-Möbius topology switch that is controlled by temperature, like in the case of the closed-shell precursor. The unpaired electron interacting with magnetic nuclei in the molecule is used as a sensitive probe for the electronic structure and its symmetry properties. For a Hückel conformer with its higher symmetry, we expect – and observe – fewer ENDOR lines than for a Möbius conformer. The ENDOR results are supplemented by and in accordance with theoretical calculations based on density functional theory at the ORCA level.
    Physical Chemistry Chemical Physics 02/2015; 17(9). DOI:10.1039/C4CP05745G · 4.49 Impact Factor
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    ABSTRACT: [FeFe]-hydrogenases are to date the only enzymes for which it has been demonstrated that the native inorganic binuclear cofactor of the active site Fe2(adt)(CO)3(CN)2 (adt = azadithiolate = [S-CH2-NH-CH2-S](2-)) can be synthesized on the laboratory bench and subsequently inserted into the unmaturated enzyme to yield fully functional holo-enzyme (Berggren, G. et al. (2013) Nature 499, 66?70, Esselborn, J. et al. (2013) Nat Chem Biol 9, 607?610). In the current study, we exploit this procedure to introduce non-native cofactors into the enzyme. Mimics of the binuclear sub-cluster with a modified bridging dithiolate ligand (thiodithiolate, N-methylazadithiolate, dimethyl-azadithiolate) and three variants containing only one CN(-) ligand were inserted into the active site of the enzyme. We investigate the activity of these variants for hydrogen oxidation as well as proton reduction and their structural accommodation within the active site was analyzed using Fourier transform infrared spectroscopy. Interestingly, the mono-cyanide variant with the azadithiolate bridge showed ?50% of the native Enzyme activity. This would suggest that the CN(-) ligands are not essential for catalytic activity but rather serve to anchor the binuclear subsite inside the protein pocket through hydrogen bonding. The inserted artificial cofactors with a propanedithiolate and an N-methylazadithiolate bridge as well as their mono-cyanide variants also showed residual activity. However, these activities were less than 1% of the native enzyme. Our findings indicate that even small changes in the dithiolate bridge of the binuclear sub-site lead to a rather strong decrease of the catalytic activity. We conclude that both the Br?nsted base function and the conformational flexibility of the native azadithiolate amine moiety are essential for the high catalytic activity of the native enzyme.
    Biochemistry 01/2015; 54(7). DOI:10.1021/bi501391d · 3.02 Impact Factor

Publication Stats

12k Citations
2,144.84 Total Impact Points


  • 2004-2015
    • Max Planck Institute for Chemical Energy Conversion
      Mülheim-on-Ruhr, North Rhine-Westphalia, Germany
  • 2003-2015
    • Max Planck Institute for Chemistry
      Mayence, Rheinland-Pfalz, Germany
  • 2007
    • Semenov Institute of Chemical Physics
      Moskva, Moscow, Russia
  • 1991-2007
    • Technische Universität Berlin
      • Department of Chemistry
      Berlín, Berlin, Germany
  • 2001
    • VU University Amsterdam
      • Division of Theoretical Chemistry
      Amsterdamo, North Holland, Netherlands
  • 1975-2001
    • Freie Universität Berlin
      • Institute of Experimental Physics
      Berlín, Berlin, Germany
  • 1996
    • Arizona State University
      • Department of Chemistry and Biochemistry
      Mesa, AZ, United States
  • 1995
    • Max Planck Institute for Biophysical Chemistry
      Göttingen, Lower Saxony, Germany
  • 1985-1995
    • University of California, San Diego
      • Department of Physics
      San Diego, California, United States
  • 1983
    • Goethe-Universität Frankfurt am Main
      • Institut für Anorganische und Analytische Chemie
      Frankfurt, Hesse, Germany
  • 1980
    • University of Jyväskylä
      • Department of Chemistry
      Jyväskylä, Western Finland, Finland