Bernhard Brutschy

Goethe-Universität Frankfurt am Main, Frankfurt, Hesse, Germany

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Publications (145)544.18 Total impact

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    ABSTRACT: We present the bioconjugation of avidin as a central and/or bridging building block with mono-, bi- and tetravalent biotinylated glycodendrimers to fabricate defined supramolecular nanostructures for future (bio)medical applications. For this purpose mono-, bi- and tetravalent biotinylated glycodendrimers, decorated with short alkyl-linked or long PEG-linked biotin ligands, were synthesized and characterized by NMR, IR and mass spectrometry and HABA displacement assay. Various techniques (UV/Vis, DLS, TEM, LILBID-MS and AF4) were used in order to obtain information about the structural properties of different conjugates of avidin and mono-, bi- and tetravalent biotinylated glycodendrimers. The biotin ligand’s spacer length, its chemical structure and the degree of biotin functionalization are essential parameters in the formation of nanostructures with avidin having a controlled composition and size dimension up to 100 nm. Biohybrid structures with avidin as a central unit require monovalent glycodendrimers with PEG-linked biotin, while bi- and tetravalent glycodendrimers with short alkyl-linked biotin ligands are more efficient than their counterparts with longer PEG–biotin ligands in the fabrication of defined biohybrid structures (B up to 100 nm) with avidin as a bridging unit. The most dominating key issue, combined with other conjugation issues, is the optimal ligand–receptor stoichiometry to fabricate biohybrid structures with diameter of <20, <30 or up to 100 nm.
    Polymer Chemistry 02/2014; 5(4):1323-1339. DOI:10.1039/c3py01152f · 5.52 Impact Factor
  • Chayan Kanti Nandi · Hans-Dieter Barth · Bernhard Brutschy
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    ABSTRACT: We have developed a new laser source, for the spectroscopy of nonvolatile molecules in gas phase. It is based on a laser induced liquid bead ion desorption source (LILBID) combined with a supersonic beam. The cold molecules produced with this technique are sampled with Resonant Two Photon Ionization spectroscopy (R2PI) to measurement of the gas phase optical spectra. LILBID allows to bring nonvolatile molecule from liquid phase (out of a droplet), into gas phase, by means of multi photon ablation with IR photons exciting the vibrations of the solvent. Phenol and its different water clusters have been used as an example to demonstrate the method and to standardise the new experimental setup. The recorded R2PI spectral data of phenol monomer and its different water clusters obtained from this laser desorption technique are in very good agreement with the previously published data. This technique opens a new door for the measurement of molecules under microsolvation and potentially for zwitterion formation of thermally labile, nonvolatile molecules such as amino acids or biomolecules.
    Zeitschrift für Physikalische Chemie 01/2014; 228(4-5). DOI:10.1515/zpch-2013-0460 · 1.36 Impact Factor
  • Rolf Michels · Thomas Sinemus · Jan Hoffmann · Bernhard Brutschy · Klaus Huber
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    ABSTRACT: The present work investigates the formation of well-defined hetero-aggregates from a binary mixture of a red and a yellow azo-dyestuff in the presence of Mg2+ ions. Combined static and dynamic light scattering together with laser induced liquid bead ion desorption mass spectrometry (LILBID-MS) has been applied to characterize the states of the pure red dye and the pure yellow dye as well as of their mixture in aqueous solution without Mg2+. These experiments indicated that a structural reorganization on a molecular scale takes place as soon as the two dyes are combined. Solutions of the combined red and yellow dye contain micelle-like mixed entities with a size of a few tenths of nanometers. Upon the addition of Mg2+, these micelles vanish in favour of elongated hetero-aggregates, which grow by a stepwise addition of smaller building units. As unraveled by UV/vis spectroscopy, the hetero-aggregates that are formed from the red and yellow azo dye in the presence of Mg2+ obeys a stoichiometric ratio of the two components of 1:1. A new multi-angle scattering instrument allowed for the first time to follow this aggregation process at the stoichiometric ratio by time-resolved combined static and dynamic light scattering, thereby providing further aspects of the worm-like nature of the growing hetero-aggregates.
    The Journal of Physical Chemistry B 06/2013; 117(28). DOI:10.1021/jp403985m · 3.30 Impact Factor
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    ABSTRACT: The vibrational fingerprints of hydrogen-bonding associated with the adenine-thymine (A-T) Watson-Crick (WC) base pair have been identified in an infrared study of the A-T mimics 4-aminopyrimidine-1-methylthymine (4APM-1MT) and 4-aminopyrimidine-6-methyl-4-pyrimidinone (4APM-M4PMN) in the gas-phase. The IR vibrational spectra were measured via a double resonance scheme utilizing femtosecond multiphoton ionization. The changes in the molecular structure, anharmonic vibrational parameters, and the assignment of the observed vibrational spectra in the NH/CH stretch region were investigated by carrying out high-level theoretical calculations of the anharmonic spectra. The experimental observations and theoretical calculations indicate that the hydrogen bonds associated with WC base-pairing are relatively stronger than those associated with reverse WC (rWC) base pairing. This is manifested in a more pronounced red-shift of the H-bonded vibrational modes associated with the WC as compared with the rWC base-pairing. An analysis of the factors contributing to the anharmonicity of the vibrational modes associated with H-bonding reveals that the magnitude of the off-diagonal anharmonic coupling of the H-bonded -NH2 stretch and the -NH2 bend is much smaller in WC base-pairing than in the corresponding rWC base-pairing. The chemical and biological implications of these results, especially in the context of using vibrational spectroscopy as a tool for identifying the signatures of nucleotide base vibrations is addressed.
    Physical Chemistry Chemical Physics 06/2013; 15(27):11520-11530. DOI:10.1039/c3cp50337b · 4.49 Impact Factor
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    ABSTRACT: Prion diseases are characterized by the accumulation of PrP(Sc), an aberrantly folded isoform of the host protein PrP(C). Specific forms of synthetic molecules known as dendrimers are able to eliminate protease resistant PrP(Sc) in both an intracellular and in vitro setting. The properties of a dendrimer which govern this ability are unknown. We addressed the issue by comparing the in vitro anti-prion ability of numerous modified poly(propylene imine) dendrimers, which varied in size, structure, charge and surface group composition. Several of the modified dendrimers, including an anionic glycodendrimer, reduced the level of protease resistant PrP(Sc) in a prion strain dependent manner. This led to the formulation of a new working model for dendrimer/prion interactions which proposes dendrimers eliminate PrP(Sc) by destabilizing the protein and rendering it susceptible to proteolysis. This ability is not dependent on any particular charge of dendrimer but does require a high density of reactive surface groups.
    Biomacromolecules 12/2012; 14(1). DOI:10.1021/bm301165u · 5.75 Impact Factor
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    ABSTRACT: Reliable assignment of 55 out of 57 vibrational modes has been achieved for 1H-pyrrolo[3,2-h]quinoline using IR, Raman, and fluorescence spectroscopy combined with quantum-chemical calculations. The experiments provided a data set for assessing the performance of different models/basis sets for predicting the vibrational frequencies, as well as IR and Raman intensities for a molecule with 13 heavy atoms. Among six different tested DFT functionals, the hybrid B3LYP used with Pople's split-valence basis sets is suggested as the best choice for accurate and cost-effective IR/Raman spectral simulations. Neither HF nor MP2 methods can satisfactorily describe the vibrational structure. Increasing the basis set size from double to triple zeta and by adding polarization and diffuse functions does not necessarily improve the results, especially regarding the predictions of vibrational frequencies. With respect to the intensities, extending the basis set helps, with the accuracy increasing systematically for the Raman spectra, and in a less regular fashion for the IR. A large difference in accuracy is observed while comparing the spectral parameters predicted for in-plane and out-of-plane normal modes. The former are reliably computed with modest basis sets, whereas for the out-of-plane vibrations, larger basis sets are necessary, but even in this case the out-of-plane vibrations are reproduced with much less accuracy than in-plane modes. This effect is general, as it has been observed using different functional and basis sets.
    The Journal of Physical Chemistry A 11/2012; 116(48). DOI:10.1021/jp309618b · 2.69 Impact Factor
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    ABSTRACT: Here, we report on the key feature of the third and fifth generation poly(propylene imine) dendrimers, bearing on the surface hydrophobic phenyl and hydrophilic maltose groups, to self-assemble into necklace- and donut-like supramolecular complex structures after ultrasound treatment of the native aggregation state.
    Polymer Chemistry 09/2012; 2012(3):3239. DOI:10.1039/c2py20649h · 5.52 Impact Factor
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    ABSTRACT: The RNA export adaptor protein Rec, encoded for by the human endogenous retrovirus HERV-K/HML-2 elements, binds to the Rec responsive element (RcRE) located in the 3' untranslated region of HERV-K/HML-2 transcripts. Binding allows the nucleocytoplasmic export of unspliced viral RNA, thereby overcoming host restriction. Chemical probing of the secondary structure of the RcRE corroborated the theory that the RcRE forms a complex folded structure with seven stem-loop regions. Laser-induced liquid beam ion desorption mass spectrometry revealed that Rec forms stable tetramers, which are further stabilized upon RNA binding. The RNA protein complex consists of three Rec tetramers, which bind to multiple sites on the RcRE-preferentially to purine-rich motifs-which represent several low-affinity binding sites. Mutated RcREs, with one to three purine-rich motifs deleted, were still bound and exported by Rec, indicating that the complex folded structure of the RcRE is important for Rec binding. This suggests a binding model where up to three Rec tetramers bind to the complex folded structure of the RcRE and the binding seems to be tightened by recognition of the purine-rich motifs.
    Journal of Virology 06/2012; 86(17):9079-87. DOI:10.1128/JVI.00121-12 · 4.44 Impact Factor
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    ABSTRACT: In the present work, the recently developed laser-induced liquid bead ion desorption mass spectrometry (LILBID MS) is applied as a novel technique to study Aβ oligomerization, thought to be crucial in Alzheimer's disease (AD). The characterization of the earliest nucleation events of this peptide necessitates the application of several techniques to bridge the gap between small oligomers and large fibrils. We precisely monitored in time the transformation of monomeric Aβ (1-42) into oligomeric Aβ(n) (n < 20) and its dependence on concentration and agitation. The distribution shows signs of the hexamer being crucial in the assembly process. The intensity of the monomer decreases in time with a time constant of about 9 h. After a lag time of around 10 h, a phase transition occurred in which the total ion current of the oligomers goes to nearly zero. In this late stage of aggregation, protofibrils are formed and mass spectrometry is no longer sensitive. Here fluorescence correlation spectroscopy (FCS) and transmission electron microscopy (TEM) are complementary tools for detection and size characterization of these large species. We also utilized the oligomers of Aβ (1-42) as a model of the corresponding in vivo process to screen the efficacy and specificity of small molecule inhibitors of oligomerization. The LILBID results are in excellent agreement with condensed phase behavior determined in other studies. Our data identified LILBID MS as a powerful technique that will advance the understanding of peptide oligomerization in neurodegenerative diseases and represents a powerful tool for the identification of small oligomerization inhibitors.
    Analytical Chemistry 05/2012; 84(12):5276-84. DOI:10.1021/ac300258m · 5.64 Impact Factor
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    ABSTRACT: The respiratory cytochrome bc(1) complex is a fundamental enzyme in biological energy conversion. It couples electron transfer from ubiquinol to cytochrome c with generation of proton motive force which fuels ATP synthesis. The complex from the α-proteobacterium Paracoccus denitrificans, a model for the medically relevant mitochondrial complexes, lacked structural characterization. We show by LILBID mass spectrometry that truncation of the organism-specific, acidic N-terminus of cytochrome c(1) changes the oligomerization state of the enzyme to a dimer. The fully functional complex was crystallized and the X-ray structure determined at 2.7-Å resolution. It has high structural homology to mitochondrial complexes and to the Rhodobacter sphaeroides complex especially for subunits cytochrome b and ISP. Species-specific binding of the inhibitor stigmatellin is noteworthy. Interestingly, cytochrome c(1) shows structural differences to the mitochondrial and even between the two Rhodobacteraceae complexes. The structural diversity in the cytochrome c(1) surface facing the ISP domain indicates low structural constraints on that surface for formation of a productive electron transfer complex. A similar position of the acidic N-terminal domains of cytochrome c(1) and yeast subunit QCR6p is suggested in support of a similar function. A model of the electron transfer complex with membrane-anchored cytochrome c(552), the natural substrate, shows that it can adopt the same orientation as the soluble substrate in the yeast complex. The full structural integrity of the P. denitrificans variant underpins previous mechanistic studies on intermonomer electron transfer and paves the way for using this model system to address open questions of structure/function relationships and inhibitor binding.
    Biochimica et Biophysica Acta 12/2011; 1807(12):1606-15. DOI:10.1016/j.bbabio.2011.09.017 · 4.66 Impact Factor
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    ABSTRACT: Human 5-lipoxygenase (5-LO) can form dimers as shown here via native gel electrophoresis, gel filtration chromatography and LILBID (laser induced liquid bead ion desorption) mass spectrometry. After glutathionylation of 5-LO by diamide/glutathione treatment, dimeric 5-LO was no longer detectable and 5-LO almost exclusively exists in the monomeric form which showed full catalytic activity. Incubation of 5-LO with diamide alone led to a disulfide-bridged dimer and to oligomer formation which displays a strongly reduced catalytic activity. The bioinformatic analysis of the 5-LO surface for putative protein-protein interaction domains and molecular modeling of the dimer interface suggests a head to tail orientation of the dimer which also explains the localization of previously reported ATP binding sites. This interface domain was confirmed by the observation that 5-LO dimer formation and inhibition of activity by diamide was largely prevented when four cysteines (C159S, C300S, C416S, C418S) in this domain were mutated to serines.
    Biological Chemistry 12/2011; 392(12):1097-111. DOI:10.1515/BC.2011.200 · 3.27 Impact Factor
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    Markus Steber · Amit Arora · Jan Hofmann · Bernhard Brutschy · Beatrix Suess
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    ABSTRACT: The TetR aptamer induces TetR controlled gene expression, and represents an interesting tool for application in synthetic biology. We have analysed the mechanistic basis for RNA aptamer-based induction of TetR. The aptamer binds TetR with a high affinity in the order of 10(7)  M(-1), which is similar to operator DNA binding under the used ionic conditions. We identified the binding epitope of the aptamer on TetR, which consists of amino acids T27, N47 and K48 of both monomers, using loss-of-function analysis and electrophoretic mobility shift assays. Tetracycline-induced conformational changes of TetR led to reorientation of the DNA reading head. This movement destroys the composite binding epitope for the aptamer and leads to reduced RNA binding by one order of magnitude. The aptamer can actively displace TetR from the operator DNA; this could be the key factor for its activity in vivo.
    ChemBioChem 11/2011; 12(17):2608-14. DOI:10.1002/cbic.201100503 · 3.09 Impact Factor
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    ABSTRACT: Abstract Human 5-lipoxygenase (5-LO) can form dimers as shown here via native gel electrophoresis, gel filtration chromatography and LILBID (laser induced liquid bead ion desorption) mass spectrometry. After glutathionylation of 5-LO by diamide/glutathione treatment, dimeric 5-LO was no longer detectable and 5-LO almost exclusively exists in the monomeric form which showed full catalytic activity. Incubation of 5-LO with diamide alone led to a disulfide-bridged dimer and to oligomer formation which displays a strongly reduced catalytic activity. The bioinformatic analysis of the 5-LO surface for putative protein-protein interaction domains and molecular modeling of the dimer interface suggests a head to tail orientation of the dimer which also explains the localization of previously reported ATP binding sites. This interface domain was confirmed by the observation that 5-LO dimer formation and inhibition of activity by diamide was largely prevented when four cysteines (C159S, C300S, C416S, C418S) in this domain were mutated to serines.
    Biological Chemistry 10/2011; 392(12). DOI:10.1515/BC-2011-200 · 3.27 Impact Factor
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    ABSTRACT: Energy-coupled transporters in the outer membrane of Escherichia coli and other Gram-negative bacteria allow the entry of scarce substrates, toxic proteins, and bacterial viruses (phages) into the cells. The required energy is derived from the proton-motive force of the cytoplasmic membrane, which is coupled to the outer membrane via the ExbB-ExbD-TonB protein complex. Knowledge of the structure of this complex is required to elucidate the mechanisms of energy harvesting in the cytoplasmic membrane and energy transfer to the outer membrane transporters. Here we solubilized an ExbB oligomer and an ExbB-ExbD subcomplex from the cytoplasmic membrane with the detergent undecyl maltoside. Using laser-induced liquid bead ion desorption mass spectrometry (LILBID-MS), we determined at moderate desorption laser energies the oligomeric structure of ExbB to be mainly hexameric (ExbB(6)), with minor amounts of trimeric (ExbB(3)), dimeric (ExbB(2)), and monomeric (ExbB(1)) oligomers. Under the same conditions ExbB-ExbD formed a subcomplex consisting of ExbB(6)ExbD(1), with a minor amount of ExbB(5)ExbD(1). At higher desorption laser intensities, ExbB(1) and ExbD(1) and traces of ExbB(3)ExbD(1), ExbB(2)ExbD(1), ExbB(1)ExbD(1), ExbB(3), and ExbB(2) were observed. Since the ExbB(6) complex and the ExbB(6)ExbD(1) complex remained stable during solubilization and subsequent chromatographic purification on nickel-nitrilotriacetate agarose, Strep-Tactin, and Superdex 200, and during native blue gel electrophoresis, we concluded that ExbB(6) and ExbB(6)ExbD(1) are subcomplexes on which the final complex including TonB is assembled.
    Biochemistry 09/2011; 50(41):8950-6. DOI:10.1021/bi2008195 · 3.02 Impact Factor
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    ABSTRACT: We report the infrared spectrum of the 4-aminobenzimidazole-1-methylthymine (4ABI:1MT) heterodimer, detected by femtosecond multiphoton ionization. Based on calculations of both the harmonic and the anharmonic frequencies, the observed vibrational spectrum is assigned to a structure that mimics the Hoogsteen base pairing of adenine and thymine. A notable observation made in the course of this study is that there is a significant imbalance in the observed strengths of the H-bonds. While the N···H-N bond reveals a large red shift of >700 cm(-1) for the NH stretch frequency, the N-H···O bond is characterized by only a 50 cm(-1) shift. The importance of this observation in the formation of Hoogsteen duplexes by thymine-based oligonucleotides is discussed.
    The Journal of Physical Chemistry A 09/2011; 115(41):11403-11. DOI:10.1021/jp205575w · 2.69 Impact Factor
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    ABSTRACT: Mitochondrial complex I, the largest and most complicated proton pump of the respiratory chain, links the electron transfer from NADH to ubiquinone to the pumping of four protons from the matrix into the intermembrane space. In humans, defects in complex I are involved in a wide range of degenerative disorders. Recent progress in the X-ray structural analysis of prokaryotic and eukaryotic complex I confirmed that the redox reactions are confined entirely to the hydrophilic peripheral arm of the L-shaped molecule and take place at a remarkable distance from the membrane domain. While this clearly implies that the proton pumping within the membrane arm of complex I is driven indirectly via long-range conformational coupling, the molecular mechanism and the number, identity, and localization of the pump-sites remains unclear. Here, we report that upon deletion of the gene for a small accessory subunit of the Yarrowia complex I, a stable subcomplex (nb8mΔ) is formed that lacks the distal part of the membrane domain as revealed by single particle analysis. The analysis of the subunit composition of holo and subcomplex by three complementary proteomic approaches revealed that two (ND4 and ND5) of the three subunits with homology to bacterial Mrp-type Na(+)/H(+) antiporters that have been discussed as prime candidates for harbouring the proton pumps were missing in nb8mΔ. Nevertheless, nb8mΔ still pumps protons at half the stoichiometry of the complete enzyme. Our results provide evidence that the membrane arm of complex I harbours two functionally distinct pump modules that are connected in series by the long helical transmission element recently identified by X-ray structural analysis.
    PLoS Biology 08/2011; 9(8):e1001128. DOI:10.1371/journal.pbio.1001128 · 9.34 Impact Factor
  • Maksim Kunitski · Yevgeniy Nosenko · Bernhard Brutschy
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    ABSTRACT: The photoinduced excited-state relaxation dynamics of gaseous thymine and 1-methylthymine are studied by both femtosecond and nanosecond pump-probe ionization spectroscopy on the sub-picosecond to microsecond timescale. A threefold exponential decay is observed with time constants of 80±40 fs, 4.8±2 ps, and 280±30 ns for thymine and 70±40 fs, 3.4±1.1 ps, and 310±30 ns for 1-methylthymine using a 267 nm excitation and subsequent 800 nm multiphoton ionization. In addition, a vibrational spectrum in the NH stretch region of the long-lived "dark" electronic state of isolated 1-methylthymine is reported for the first time. This spectrum, in combination with the dependence of the dark-state ionization rate on the laser intensity, allows assignment of the dark state of 1-methylthymine to the lowest triplet state of the keto tautomer, thus excluding enol tautomers as well as the nπ* excited state and a hot electronic ground state from the consideration. Very similar excited-state relaxation dynamics of thymine and 1-methylthymine justify the conclusion that the long-lived dark state of isolated thymine is also of triplet nature.
    ChemPhysChem 07/2011; 12(10):2024-30. DOI:10.1002/cphc.201000985 · 3.42 Impact Factor
  • Yevgeniy Nosenko · Maksim Kunitski · Bernhard Brutschy
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    ABSTRACT: A photoionization detected IR study of thymine and 1-methylthymine monohydrates and of their homodimers was carried out to shed some light on the structure of the thymine clusters whose complex photodynamics has recently been the subject of great interest. Under supersonic jet conditions, thymine forms doubly H-bonded cyclic clusters with water or another base preferentially via its N1-H group and the adjacent carbonyl group. This hydrate is of no biological relevance since the N1-H group is the sugar binding site in thymidine. On the other hand, 1-methylthymine forms the donor H-bonds only via the N3-H group. Hence, properties of the N1-H and the N3-H bound clusters of thymine can be studied using thymine and 1-methylthymine molecules, respectively. No biologically relevant conformations of the dimers and hydrates of thymine, contrary to those of 1-methylthymine, are observed under supersonic jet conditions. Thymine homodimer, which extensively fragments upon UV ionization by formation of a protonated monomer, exhibits two N1-H···O═C2 hydrogen bonds. The photodynamics of hydrated thymines is found to be extremely sensitive to the hydration site: ranging from an ultrafast relaxation in less than 100 fs up to formation of a dark state with the lifetime on the microsecond time scale.
    The Journal of Physical Chemistry A 06/2011; 115(34):9429-39. DOI:10.1021/jp111373t · 2.69 Impact Factor
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    ABSTRACT: The incorporation of transition-metal ions into nucleic acids by using metal-mediated base pairs has proved to be a promising strategy for the site-specific functionalization of these biomolecules. We report herein the formation of Ag(+)-mediated Hoogsteen-type base pairs comprising 1,3-dideaza-2'-deoxyadenosine and thymidine. By defunctionalizing the Watson-Crick edge of adenine, the formation of regular base pairs is prohibited. The additional substitution of the N3 nitrogen atom of adenine by a methine moiety increases the basicity of the exocyclic amino group. Hence, 1,3-dideazaadenine and thymine are able to incorporate two Ag(+) ions into their Hoogsteen-type base pair (as compared with one Ag(+) ion in base pairs with 1-deazaadenine and thymine). We show by using a combination of experimental techniques (UV and circular dichroism (CD) spectroscopies, dynamic light scattering, and mass spectrometry) that this type of base pair is compatible with different sequence contexts and can be used contiguously in DNA double helices. The most stable duplexes were observed when using a sequence containing alternating purine and pyrimidine nucleosides. Dispersion-corrected density functional theory calculations have been performed to provide insight into the structure, formation and stabilization of the twofold metalated base pair. They revealed that the metal ions within a base pair are separated by an Ag···Ag distance of about 2.88 Å. The Ag-Ag interaction contributes some 16 kcal mol(-1) to the overall stability of the doubly metal-mediated base pair, with the dominant contribution to the Ag-Ag bonding resulting from a donor-acceptor interaction between silver 4d-type and 4s orbitals. These Hoogsteen-type base pairs enable a higher functionalization of nucleic acids with metal ions than previously reported metal-mediated base pairs, thereby increasing the potential of DNA-based nanotechnology.
    Chemistry - A European Journal 05/2011; 17(23):6533-44. DOI:10.1002/chem.201002944 · 5.73 Impact Factor
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    ABSTRACT: Mitochondrial NADH:ubiquinone oxidoreductase (complex I) is a very large membrane protein complex with a central function in energy metabolism. Complex I from the aerobic yeast Yarrowia lipolytica comprises 14 central subunits that harbour the bioenergetic core functions and at least 28 accessory subunits. Despite progress in structure determination, the position of individual accessory subunits in the enzyme complex remains largely unknown. Proteomic analysis of subcomplex Iδ revealed that it lacked eleven subunits, including the central subunits ND1 and ND3 forming the interface between the peripheral and the membrane arm in bacterial complex I. This unexpected observation provided insight into the structural organization of the connection between the two major parts of mitochondrial complex I. Combining recent structural information, biochemical evidence on the assignment of individual subunits to the subdomains of complex I and sequence-based predictions for the targeting of subunits to different mitochondrial compartments, we derived a model for the arrangement of the subunits in the membrane arm of mitochondrial complex I.
    Biochemical Journal 05/2011; 437(2):279-88. DOI:10.1042/BJ20110359 · 4.40 Impact Factor

Publication Stats

3k Citations
544.18 Total Impact Points


  • 1996–2014
    • Goethe-Universität Frankfurt am Main
      • Institute of Physical and Theoretical Chemistry
      Frankfurt, Hesse, Germany
  • 2001–2011
    • University Hospital Frankfurt
      Frankfurt, Hesse, Germany
  • 2010
    • Frankfurt Zoo
      Frankfurt, Hesse, Germany
  • 2008
    • University of Bologna
      Bologna, Emilia-Romagna, Italy
  • 1989–2007
    • Freie Universität Berlin
      • • Division of Physical and Theoretical Chemistry
      • • Institute of Theoretical Physics
      Berlin, Land Berlin, Germany
  • 2006
    • University of Houston
      • Department of Chemistry
      Houston, Texas, United States
  • 2000
    • Academy of Sciences of the Czech Republic
      • Ústav fyzikální chemie J. Heyrovského
      Praha, Hlavni mesto Praha, Czech Republic