126
|
Friedebold J, Mayer F, Bill E, Trautwein AX, Bowien B. Structural and immunological studies on the soluble formate dehydrogenase from Alcaligenes eutrophus. BIOLOGICAL CHEMISTRY HOPPE-SEYLER 1995; 376:561-8. [PMID: 8561915 DOI: 10.1515/bchm3.1995.376.9.561] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
During growth with formate as the sole energy source the autotrophic bacterium Alcaligenes eutrophus synthesizes a cytoplasmic formate dehydrogenase. The enzyme is a molybdo-iron-sulfur-flavo protein and the major NADH-producing system under these growth conditions, although it was estimated to constitute only 0.65% of the soluble cell protein. An electron microscopic analysis of the purified enzyme revealed that the particle is made up of four nonidentical submasses, corroborating previous structural data. The NH2-terminal amino acid sequences of the enzyme subunits exhibited significant similarities to those of only one other heteromeric formate dehydrogenase, the enzyme from the methane-utilizing bacterium Methylosinus trichosporium. Metal analyses yielded 21.5 g-atom iron, 2.18 g-atom nickel, 0.76 g-atom molybdenum, and 0.59 g-atom zinc per mol of enzyme. Initial electron paramagnetic resonance spectroscopic studies showed at least three distinct signals which appeared upon reduction of the enzyme with NADH or formate. The corresponding spin systems could be attributed to iron-sulfur centers of the enzyme. Comparative immunostaining and activity-staining experiments using cell extracts from various bacteria established immunological similarities between the soluble formate dehydrogenase of A. eutrophus and the soluble enzymes from all tested facultative autotrophs as well as from M. trichosporium.
Collapse
|
127
|
Gerlach M, Trautwein AX, Zecca L, Youdim MB, Riederer P. Mössbauer spectroscopic studies of purified human neuromelanin isolated from the substantia nigra. J Neurochem 1995; 65:923-6. [PMID: 7616255 DOI: 10.1046/j.1471-4159.1995.65020923.x] [Citation(s) in RCA: 95] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
57Fe Mössbauer spectroscopy at different temperatures has been used to characterize the nature of purified human neuromelanin isolated from the substantia nigra. The quantitative determination of iron(III) by estimation of the overall area of the Mössbauer spectrum at room temperature reveals an iron content of 2.8 +/- 1.4%. No subspectra corresponding to divalent iron could be observed in these spectra. The derived Mössbauer parameters lead to the conclusion that the iron sites in the human neuromelanin are similar to those of human hemosiderin (or ferritin). However, owing to the water insolubility of the purified neuromelanin, it must be concluded that the neuromelanin hemosiderin (or ferritin) is bound in a protein matrix that makes it insoluble and difficult to stain histochemically. This protein attachment to neuromelanin is important in that it is what makes it different from synthetic dopamine melanin.
Collapse
|
128
|
Jüstel T, Weyhermüller T, Wieghardt K, Bill E, Lengen M, Trautwein AX, Hildebrandt P. μ-Nitridodiiron Complexes with Asymmetric[FeIVN-FeIII]4+ and Symmetric[FeIVNFeIV]5+ Structural Elements. ACTA ACUST UNITED AC 1995. [DOI: 10.1002/anie.199506691] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
|
129
|
Charnock JM, Garner CD, Trautwein AX, Bill E, Winkler H, Ayougou K, Mandon D, Weiss R. Characterization of an Oxo(porphyrinato)manganese(IV) Complex by X-ray Absorption Spectroscopy. ACTA ACUST UNITED AC 1995. [DOI: 10.1002/anie.199503431] [Citation(s) in RCA: 51] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
|
130
|
Ayougou K, Bill E, Charnock JM, Garner CD, Mandon D, Trautwein AX, Weiss R, Winkler H. Charakterisierung eines Oxo(porphyrinato)-mangan(IV)-Komplexes mit Röntgenabsorptionsspektroskopie. Angew Chem Int Ed Engl 1995. [DOI: 10.1002/ange.19951070324] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
|
131
|
Burdinski D, Birkelbach F, Gerdan M, Trautwein AX, Wieghardt K, Chaudhuri P. Self-assembly of a novel 14-membered metallamacrobicycle containing two chromium(III) ions as part of the ring skeleton. ACTA ACUST UNITED AC 1995. [DOI: 10.1039/c39950000963] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
|
132
|
Saalfrank RW, Burak R, Breit A, Stalke D, Herbst-Irmer R, Daub J, Porsch M, Bill E, Müther M, Trautwein AX. Mixed-Valence, Tetranuclear Iron Chelate Complexes as Endoreceptors: Charge Compensation Through Inclusion of Cations. ACTA ACUST UNITED AC 1994. [DOI: 10.1002/anie.199416211] [Citation(s) in RCA: 122] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
|
133
|
Saalfrank RW, Burak R, Breit A, Stalke D, Herbst-Irmer R, Daub J, Porsch M, Bill E, Müther M, Trautwein AX. Gemischtvalente, tetranucleare Eisenchelatkomplexe als Endorezeptoren: Ladungskompensation durch Kationen-Einschluß. Angew Chem Int Ed Engl 1994. [DOI: 10.1002/ange.19941061526] [Citation(s) in RCA: 57] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
|
134
|
Ding XQ, Bill E, Trautwein AX, Hartmann HJ, Weser U. Mössbauer studies on iron(II)-substituted yeast metallothionein. EUROPEAN JOURNAL OF BIOCHEMISTRY 1994; 223:841-5. [PMID: 8055961 DOI: 10.1111/j.1432-1033.1994.tb19060.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Iron(II)-substituted yeast metallothionein has been studied with Mössbauer spectroscopy. The iron in the protein is in the high-spin ferrous state. A maximum metal content of four iron(II)/molecule has been determined, with the four metal ions forming a diamagnetic cluster due to the antiferromagnetic exchange interaction between Fe2+ via bridging thiolates. In the case where the iron titration gives a value of less than four iron(II)/apoprotein, the metal ions are magnetically noninteracting, with each individual iron(II) behaving like iron(II) in reduced rubredoxin.
Collapse
|
135
|
Gold A, Brust K, Jayaraj K, Sangaiah R, Ball LM, Trautwein AX, Bill E, Terner J. Oxidation of Polycyclic Aromatic Hydrocarbons by an Oxoferryl Porphyrin π-Cation Radical. Polycycl Aromat Compd 1994. [DOI: 10.1080/10406639408014709] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
|
136
|
Anemüller S, Schmidt CL, Schäfer G, Bill E, Trautwein AX, Teixeira M. Evidence for a two proton dependent redox equilibrium in an archaeal Rieske iron-sulfur cluster. Biochem Biophys Res Commun 1994; 202:252-7. [PMID: 8037720 DOI: 10.1006/bbrc.1994.1920] [Citation(s) in RCA: 27] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
The recently detected Rieske iron-sulfur center in the membrane of the thermoacidophilic archaeon Sulfolobus acidocaldarius (Anemüller et al., 1993, FEBS Lett. 318, 61-64) was further characterized by EPR spectroscopy, coupled to redox-potentiometry and functional studies. The reduction potential is pH-dependent above pH 6, revealing the influence of two ionization equilibria in the oxidized form, with pKaox-values of 6.2 and 8.5. Above pH 9, the slope of the curve is--120 mV/pH-unit. A partially purified fraction exerted a ubiquinol-cytochrome c oxidoreductase activity. To our knowledge, for the first time, in a membrane bound Rieske iron-sulfur protein, unequivocal evidence for a two proton dependent redox equilibrium is presented.
Collapse
|
137
|
Vogel E, Will S, Tilling AS, Neumann L, Lex J, Bill E, Trautwein AX, Wieghardt K. Metallocorroles with Formally Tetravalent Iron. ACTA ACUST UNITED AC 1994. [DOI: 10.1002/anie.199407311] [Citation(s) in RCA: 161] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
|
138
|
Vogel E, Will S, Tilling AS, Neumann L, Lex J, Bill E, Trautwein AX, Wieghardt K. Metallocorrole mit formal vierwertigem Eisen. Angew Chem Int Ed Engl 1994. [DOI: 10.1002/ange.19941060708] [Citation(s) in RCA: 55] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
|
139
|
Ding XQ, Butzlaff C, Bill E, Pountney DL, Henkel G, Winkler H, Vasák M, Trautwein AX. Mössbauer and magnetic susceptibility studies on iron(II) metallothionein from rabbit liver. Evidence for the existence of an unusual type of [M3(CysS)9]3- cluster. EUROPEAN JOURNAL OF BIOCHEMISTRY 1994; 220:827-37. [PMID: 8143737 DOI: 10.1111/j.1432-1033.1994.tb18685.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
The magnetic properties of the Fe(II)-binding sites in Fe(II)7-metallothionein (MT) have been studied using Mössbauer spectroscopy and magnetic-susceptibility measurements. In agreement our previous results, simulation of the Mössbauer spectra showed the presence of paramagnetic and diamagnetic subspectra in the ratio 3:4. By comparison with Mössbauer spectra of the inorganic adamantane-like (Et4N)2[Fe4(SEt)10] model compound, the diamagnetic component in Fe(II)7-MT has been assigned to a four-metal cluster in which there is antiferromagnetic coupling between the high-spin Fe(II) ions. It is suggested that the organization of this cluster is similar to that determined in the three-dimensional structure of the protein, containing diamagnetic Zn(II) and/or Cd(II) ions. From magnetic-susceptibility studies, an average magnetic moment of approximately 8.5 microB was obtained for the three remaining bound Fe(II) ions, responsible for the paramagnetic component observed in the Mössbauer studies. This value is slightly lower than that for three completely uncoupled Fe(II) ions, suggesting the existence of a three-metal cluster within which there is weak exchange coupling between adjacent Fe(II) ions. The spin-Hamiltonian formalism including, besides zero-field and Zeeman interaction, also exchange interaction among the three Fe(II) ions in the three-metal cluster, H = -J12 (S1.S2)-J23 (S2.S3)-J13 (S1.S3), was applied to simulate both magnetic-Mössbauer and magnetic-susceptibility data. Reasonable fits were achieved only with values magnitude of J12 = magnitude of J23 = magnitude of J13 = magnitude of J < 1 cm-1. Such a situation could not be reconciled with the chair-like geometry of the [M3(CysS)9]3- cluster determined with paramagnetic metal ions, where significantly stronger coupling would be anticipated (magnitude of J = 50-70 cm-1). However, modest exchange-coupling properties have been reported for a number of crystallographically characterized trinuclear [Fe3(SR)3X6]3- clusters (X = Cl, Br; R = Phe, p-tolyl, 2,6-Me2C6H3) distinguished by the preferential formation of a planar Fe3(mu 2-SR)3 ring [Whitener, M. A., Bashkin, J. A., Hagen, K. S., Girerd, J.-J., Gamp, E. Edelstein, N. & Holm, R. H. (1986) J. Amer. Chem. Soc. 108, 5607-5620]. It is therefore more likely that a pseudo-planar geometry rather than a chair-like geometry is present in the Fe3 cluster of Fe(II)7-MT. This would represent the first example of structural differences on binding divalent metal ions to this protein.
Collapse
|
140
|
Mochizuki K, Kesting F, Weyhermüller T, Wieghardt K, Butzlaff C, Trautwein AX. Synthesis, molecular and electronic structure of complexes [LNaMIVNaL](MRu,Os; H3L = 1,4,7-tris(4-tert-butyl-2-mercaptobenzyl)-1,4,7-triazacyclononane). ACTA ACUST UNITED AC 1994. [DOI: 10.1039/c39940000909] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
|
141
|
Siemeling U, Jutzi P, Bill E, Trautwein AX. Zu metall-metall-wechselwirkungen in komplexen eines doppelt dimethylsilandiyl-verbrückten dicyclopentadienyl-liganden. J Organomet Chem 1993. [DOI: 10.1016/0022-328x(93)83412-o] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
|
142
|
Knof U, Weyhermüller T, Wolter T, Wieghardt K, Bill E, Butzlaff C, Trautwein AX. Wie „unschuldig” sind Pentan-2,4-dion-bis(S-alkyl-isothiosemicarbazonato)-Liganden in biomimetischen FeII- und FeIV-Komplexen? Angew Chem Int Ed Engl 1993. [DOI: 10.1002/ange.1761051128] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
|
143
|
Knof U, Weyhermüller T, Wolter T, Wieghardt K, Bill E, Butzlaff C, Trautwein AX. Wie „unschuldig”︁ sind Pentan-2,4-dion-bis( S-alkylisothiosemicarbazonato)-Liganden in biomimetischen Fe II- und Fe IV-Komplexen? Angew Chem Int Ed Engl 1993. [DOI: 10.1002/ange.19931051127] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
|
144
|
Knof U, Weyhermüller T, Wolter T, Wieghardt K, Bill E, Butzlaff C, Trautwein AX. How“Innocent” Are Pentane-2,4-dionebis(S-alkylisothiosemicarbazonato) Ligands in Biomimetic FeII and FeIV Complexes? ACTA ACUST UNITED AC 1993. [DOI: 10.1002/anie.199316351] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
|
145
|
Ochsenbein P, Mandon D, Fischer J, Weiss R, Austin R, Jayaraj K, Gold A, Terner J, Bill E, Müther M, Trautwein AX. Das Oxoferryl-π-Radikalkation vonmeso-Tetramesitylporphyrin mit achtfach in β-Stellung chlorierten Pyrroleinheiten: elektronische und strukturelle Eigenschaften. Angew Chem Int Ed Engl 1993. [DOI: 10.1002/ange.19931051022] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
|
146
|
Haavik J, Bill E, Lengen M, Martìnez A, Flatmark T, Trautwein AX. Characterization of the iron environment in recombinant human tyrosine hydroxylase, using Mössbauer and EPR-spectroscopy. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 1993; 338:71-6. [PMID: 7905700 DOI: 10.1007/978-1-4615-2960-6_14] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
|
147
|
Anemüller S, Bill E, Schäfer G, Trautwein AX, Teixeira M. EPR studies of cytochrome aa3 from Sulfolobus acidocaldarius. Evidence for a binuclear center in archaebacterial terminal oxidase. EUROPEAN JOURNAL OF BIOCHEMISTRY 1992; 210:133-8. [PMID: 1332857 DOI: 10.1111/j.1432-1033.1992.tb17400.x] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
The purified cytochrome aa3-type oxidase from Sulfolobus acidocaldarius (DSM 639) consists of a single subunit, containing one low-spin and one high-spin A-type hemes and copper [Anemüller, S. and Schäfer, G. (1990) Eur. J. Biochem. 191, 297-305]. The enzyme metal centers were investigated by electron paramagnetic resonance spectroscopy (EPR), coupled to redox potentiometry. The low-spin heme EPR signal has the following g-values: gz = 3.02, gy = 2.23 and gx = 1.45 and the high-spin heme exhibits an almost axial spectrum (gy = 6.03 and gx = 5.97, E/D < 0.002). In the enzyme as isolated the low-spin resonance corresponds to 95 +/- 10% of the enzyme concentration, while the high-spin signal accounts for only 40 +/- 5%. However, taking into account the redox potential dependence of the high-spin heme signal, this value also rises to 95 +/- 10%. The high-spin heme signal of the Sulfolobus enzyme shows spectral characteristics distinct from those of the Paracoccus denitrificans one: it shows a smaller rhombicity (gy = 6.1 and gx = 5.9, E/D = 0.004 for the P. denitrificans enzyme) and it is easier to saturate, having a half saturation power of 148 mW compared to 360 mW for the P. denitrificans protein, both at 10 K. The EPR spectrum of an extensively dialyzed and active enzyme sample containing only one copper atom/enzyme molecule does not display CuA-like resonances, indicating that this enzyme contains only a CUB-type center. The EPR-redox titration of the high-spin heme signal, which is assigned to cytochrome a3, gives a bell shaped curve, which was simulated by a non-interactive two step redox process, with reduction potentials of 200 +/- 10 mV and 370 +/- 10 mV at pH = 7.4. The decrease of the signal amplitude at high redox potentials is proposed to be due to oxidation of a CUB(I) center, which in the CUB(II) state is tightly spin-coupled to the heme a3 center. The reduction potential of the low-spin resonance was determined using the same model as 305 +/- 10 mV at pH = 7.4 by EPR redox titration. Addition of azide to the enzyme affects only the high-spin heme signal, consistent with the assignment of this resonance to heme a3. The results are discussed in the context of the redox center composition of quinol and cytochrome c oxidases.
Collapse
|
148
|
Matzanke BF, Bill E, Butzlaff C, Trautwein AX, Winkler H, Hermes C, Nolting HF, Barbieri R, Russo U. Evidence for polynuclear aggregates of ferric daunomycin. A Mössbauer, EPR, X-ray absorption spectroscopy and magnetic susceptibility study. EUROPEAN JOURNAL OF BIOCHEMISTRY 1992; 207:747-55. [PMID: 1321721 DOI: 10.1111/j.1432-1033.1992.tb17105.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
The interaction of the antitumor agent daunomycin (DN) with ferric iron has been analysed by Mössbauer spectroscopy, EPR, extended X-ray absorption fine structure (EXAFS), and magnetic susceptibility measurements. In contrast to literature data, at millimolar iron and anthracycline concentrations no solitary Fe(DN)3 complexes are formed in appreciable amounts. The Mössbauer spectroscopic analysis revealed severe dependencies on temperature, on the preparation procedure, the time allowed for equilibration, and on the metal/ligand ratio. The Mössbauer spectra exhibit two components: a broad magnetic sextet and a quadrupole doublet at an Fe/DN molar ratio of 1:3 and exclusively a doublet at a molar ratio of 1:20, indicating an equilibrium of these two spectral components. The EPR spectra are dominated by a signal at g(eff) = 2. Double integration of the EPR signals enabled the determination of their spin density and a correlation between EPR and Mössbauer spectra. The Mössbauer sextet species is EPR invisible and corresponds to magnetically ordered polynuclear aggregates with high magnetic anisotropy. EXAFS and susceptibility measurements provide additional evidence for the formation of polynuclear aggregates of ferric daunomycin. The quadrupole doublet species in the Mössbauer spectra correlates with the g = 2 signal in EPR. This species is also related to a magnetically ordered system, exhibiting, however, superparamagnetic behavior due to less magnetic anisotropy. Since daunomycin forms dimers in aqueous solution at millimolar concentrations, we conclude that the cooperative phenomena observed in EPR and Mössbauer spectra are a consequence of its stacking effects.
Collapse
|
149
|
Niemann A, Bossek U, Wieghardt K, Butzlaff C, Trautwein AX, Nuber B. A New Structure–Magnetism Relationship for Face-Sharing Transition-Metal Complexes with d3–d3 Electronic Configuration. ACTA ACUST UNITED AC 1992. [DOI: 10.1002/anie.199203111] [Citation(s) in RCA: 59] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
|
150
|
Niemann A, Bossek U, Wieghardt K, Butzlaff C, Trautwein AX, Nuber B. Eine neue Struktur-Magnetismus-Beziehung für flächenverknüpfte Übergangsmetallkomplexe mit d3-d3-Elektronenkonfiguration. Angew Chem Int Ed Engl 1992. [DOI: 10.1002/ange.19921040332] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
|