Publications (24)108.74 Total impact
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Dataset: JAC TMAO 2011
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Dataset: JAC TMAO 2011
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Article: ID29: a high-intensity highly automated ESRF beamline for macromolecular crystallography experiments exploiting anomalous scattering.
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ABSTRACT: ID29 is an ESRF undulator beamline with a routinely accessible energy range of between 20.0 keV and 6.0 keV (λ = 0.62 Å to 2.07 Å) dedicated to the use of anomalous dispersion techniques in macromolecular crystallography. Since the beamline was first commissioned in 2001, ID29 has, in order to provide an improved service to both its academic and proprietary users, been the subject of almost continuous upgrade and refurbishment. It is now also the home to the ESRF Cryobench facility, ID29S. Here, the current status of the beamline is described and plans for its future are briefly outlined.Journal of Synchrotron Radiation 05/2012; 19(Pt 3):455-61. · 2.73 Impact Factor -
Article: On the routine use of soft X-rays in macromolecular crystallography. Part V. Molecular replacement and anomalous scattering.
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ABSTRACT: Currently, about two thirds of all new macromolecular structures are determined by molecular replacement. In general the method works reliably, but it reaches its limits when the search model differs too much from the target structure in terms of coordinate deviations or completeness. Since anomalously scattering substructures are better conserved than the overall structure, these substructures and the corresponding anomalous intensity differences can be utilized to enhance the performance of molecular-replacement approaches. It is demonstrated that the combined and concomitant use of structure-factor amplitudes and anomalous differences constitutes a promising approach to push the limits of molecular replacement and to make more structures amenable to structure solution by this technique.Acta crystallographica. Section D, Biological crystallography 08/2011; 67(Pt 8):729-38. · 12.67 Impact Factor -
Article: Cloning, expression, purification and preliminary X-ray analysis of the protein kinase domain of constitutive triple response 1 (CTR1) from Arabidopsis thaliana.
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ABSTRACT: Ethylene, a gaseous plant hormone, is perceived by a group of membrane-bound receptors. Constitutive triple response 1 (CTR1) from Arabidopsis thaliana directly interacts with ethylene receptors and thus links signal reception to the intracellular signalling pathway. The C-terminal protein kinase domain of CTR1 has been crystallized in its wild-type form and as a kinase-dead mutant. The wild-type crystals diffracted X-ray radiation to 3 Å resolution and the crystals of the kinase-dead mutant diffacted to 2.5 Å resolution. The crystals belonged to space groups P4(1)2(1)2 and P4(2)2(1)2, respectively, with two molecules per asymmetric unit in both cases.Acta Crystallographica Section F Structural Biology and Crystallization Communications 01/2011; 67(Pt 1):117-20. · 0.51 Impact Factor -
Article: MxCuBE: a synchrotron beamline control environment customized for macromolecular crystallography experiments.
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ABSTRACT: The design and features of a beamline control software system for macromolecular crystallography (MX) experiments developed at the European Synchrotron Radiation Facility (ESRF) are described. This system, MxCuBE, allows users to easily and simply interact with beamline hardware components and provides automated routines for common tasks in the operation of a synchrotron beamline dedicated to experiments in MX. Additional functionality is provided through intuitive interfaces that enable the assessment of the diffraction characteristics of samples, experiment planning, automatic data collection and the on-line collection and analysis of X-ray emission spectra. The software can be run in a tandem client-server mode that allows for remote control and relevant experimental parameters and results are automatically logged in a relational database, ISPyB. MxCuBE is modular, flexible and extensible and is currently deployed on eight macromolecular crystallography beamlines at the ESRF. Additionally, the software is installed at MAX-lab beamline I911-3 and at BESSY beamline BL14.1.Journal of Synchrotron Radiation 09/2010; 17(5):700-7. · 2.73 Impact Factor -
Article: Diffraction cartography: applying microbeams to macromolecular crystallography sample evaluation and data collection.
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ABSTRACT: Crystals of biological macromolecules often exhibit considerable inter-crystal and intra-crystal variation in diffraction quality. This requires the evaluation of many samples prior to data collection, a practice that is already widespread in macromolecular crystallography. As structural biologists move towards tackling ever more ambitious projects, new automated methods of sample evaluation will become crucial to the success of many projects, as will the availability of synchrotron-based facilities optimized for high-throughput evaluation of the diffraction characteristics of samples. Here, two examples of the types of advanced sample evaluation that will be required are presented: searching within a sample-containing loop for microcrystals using an X-ray beam of 5 microm diameter and selecting the most ordered regions of relatively large crystals using X-ray beams of 5-50 microm in diameter. A graphical user interface developed to assist with these screening methods is also presented. For the case in which the diffraction quality of a relatively large crystal is probed using a microbeam, the usefulness and implications of mapping diffraction-quality heterogeneity (diffraction cartography) are discussed. The implementation of these techniques in the context of planned upgrades to the ESRF's structural biology beamlines is also presented.Acta crystallographica. Section D, Biological crystallography 08/2010; 66(Pt 8):855-64. · 12.67 Impact Factor -
Article: Cloning, expression, purification, crystallization and preliminary X-ray crystallographic analysis of interleukin-4-inducing principle from Schistosoma mansoni eggs (IPSE/alpha-1).
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ABSTRACT: The interleukin-4-inducing principle from Schistosoma mansoni eggs (IPSE/alpha-1) triggers the release of large amounts of interleukin-4 from human blood basophils, thus presumably playing an immunomodulatory role during schistosome infection. IPSE/alpha-1 was crystallized and a native X-ray data set was collected to 1.66 A resolution from a single crystal at 100 K using synchrotron radiation. The crystal belonged to space group P6(1) or P6(5), with one molecule per asymmetric unit.Acta Crystallographica Section F Structural Biology and Crystallization Communications 07/2009; 65(Pt 6):594-6. · 0.51 Impact Factor -
Article: Cloning, expression, purification and crystallization as well as X-ray fluorescence and preliminary X-ray diffraction analyses of human ADP-ribosylhydrolase 1.
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ABSTRACT: Human ADP-ribosylhydrolase 1 (hARH1, ADPRH) cleaves the glycosidic bond of ADP-ribose attached to an Arg residue of a protein. hARH1 has been cloned, expressed heterologously in Escherichia coli, purified and crystallized in complex with K(+) and ADP. The orthorhombic crystals contained one monomer per asymmetric unit, exhibited a solvent content of 43% and diffracted X-rays to a resolution of 1.9 A. A prerequisite for obtaining well diffracting crystals was the performance of X-ray fluorescence analysis on poorly diffracting apo hARH1 crystals, which revealed the presence of trace amounts of K(+) in the crystal. Adding K-ADP to the crystallization cocktail then resulted in a crystal of different morphology and with dramatically improved diffraction properties.Acta Crystallographica Section F Structural Biology and Crystallization Communications 06/2009; 65(Pt 5):529-32. · 0.51 Impact Factor -
Article: Cloning, expression, purification, crystallization and preliminary X-ray diffraction analysis of the small subunit of isopropylmalate isomerase (Rv2987c) from Mycobacterium tuberculosis.
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ABSTRACT: Two C-terminally truncated variants of the small subunit of Mycobacterium tuberculosis isopropylmalate isomerase (Rv2987c; LeuD), LeuD_1-156 and LeuD_1-168, have been cloned, heterologously expressed in Escherichia coli, purified using standard chromatographic techniques and crystallized. The crystals of LeuD_1-156 belonged to the hexagonal system (space group P6(1)22 or P6(5)22) with up to four subunits in the asymmetric unit, whereas the crystals of LeuD_1-168 belonged to the monoclinic system (space group P2(1)) with two subunits in the asymmetric unit. Both crystals diffracted X-rays to beyond 2.0 A resolution and were suitable for further crystallographic analysis.Acta Crystallographica Section F Structural Biology and Crystallization Communications 03/2009; 65(Pt 2):136-9. · 0.51 Impact Factor -
Article: Structure of mouse ADP-ribosylhydrolase 3 (mARH3).
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ABSTRACT: ADP-ribosylation is a reversible and covalent post-translational modification in which the attachment of ADP-ribose is catalyzed by ADP-ribosyltransferases and the removal of ADP-ribose is catalyzed by ADP-ribosylhydrolases. ADP-ribosylhydrolase 3 from mouse, consisting of 347 amino-acid residues, has been cloned, purified and crystallized. The three-dimensional structure has been resolved at a resolution of 1.8 A. The structure constitutes a compact all-alpha-helical protein with two Mg(2+) ions located in the active-site crevice. A structural comparison of mouse ADP-ribosylhydrolase 3 with its human orthologue shows a high degree of structural similarity. Furthermore, four prokaryotic proteins deposited in the PDB could be identified as being structurally related.Acta Crystallographica Section F Structural Biology and Crystallization Communications 04/2008; 64(Pt 3):156-62. · 0.51 Impact Factor -
Article: Mammalian ADP-ribosyltransferases and ADP-ribosylhydrolases.
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ABSTRACT: ADP-ribosyltransferases (ARTs) and ADP-ribosylhydrolases (ARHs) catalyze opposing reactions, which are termed ADP-ribosylation and de-ADP-ribosylation. ARTs transfer the ADP-ribose unit from NAD (nicotinamide adenine dinucleotide) onto an acceptor, while ARHs release the ADP-ribose from the target. Like protein phosphorylation, ADP-ribosylation is a posttranslational modification regulating protein function. In many cases, ADP-ribosylation inactivates the target protein. Numerous bacterial toxins intoxicate cells by attaching an ADP-ribose moiety to a functionally important amino acid residue, thereby blocking the interaction of the target protein with other proteins. In other cases, ADP-ribosylation activates protein function. On the surface of T cells, ART2.2 ADP-ribosylates the P2X7 purinoceptor on arginine 125, thereby gating the P2X7 ion channel by presenting a ligand to its nucleotide-binding site. ADP-ribosylation is not limited to protein targets and ARTs have been described that ADP-ribosylate DNA, RNA, and small molecules. Mammalian cells express distinct families of ARTs and ARHs. Recently, molecular cloning, site directed mutagenesis and three-dimensional structural analyses of prototype mammalian ARTs and ARHs have shed fresh insight into the structure and function of these intriguing enzymes.Frontiers in Bioscience 02/2008; 13:6716-29. · 3.52 Impact Factor -
Article: On the routine use of soft X-rays in macromolecular crystallography. Part IV. Efficient determination of anomalous substructures in biomacromolecules using longer X-ray wavelengths.
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ABSTRACT: 23 different crystal forms of 19 different biological macromolecules were examined with respect to their anomalously scattering substructures using diffraction data collected at a wavelength of 2.0 A (6.2 keV). In more than 90% of the cases the substructure was found to contain more than just the protein S atoms. The data presented suggest that chloride, sulfate, phosphate or metal ions from the buffer or even from the purification protocol are frequently bound to the protein molecule and that these ions are often overlooked, especially if they are not bound at full occupancy. Thus, in order to fully describe the macromolecule under study, it seems desirable that any structure determination be complemented with a long-wavelength data set.Acta Crystallographica Section D Biological Crystallography 04/2007; 63(Pt 3):366-80. · 12.62 Impact Factor -
Article: The structure of human ADP-ribosylhydrolase 3 (ARH3) provides insights into the reversibility of protein ADP-ribosylation.
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ABSTRACT: Posttranslational modifications are used by cells from all kingdoms of life to control enzymatic activity and to regulate protein function. For many cellular processes, including DNA repair, spindle function, and apoptosis, reversible mono- and polyADP-ribosylation constitutes a very important regulatory mechanism. Moreover, many pathogenic bacteria secrete toxins which ADP-ribosylate human proteins, causing diseases such as whooping cough, cholera, and diphtheria. Whereas the 3D structures of numerous ADP-ribosylating toxins and related mammalian enzymes have been elucidated, virtually nothing is known about the structure of protein de-ADP-ribosylating enzymes. Here, we report the 3Dstructure of human ADP-ribosylhydrolase 3 (hARH3). The molecular architecture of hARH3 constitutes the archetype of an all-alpha-helical protein fold and provides insights into the reversibility of protein ADP-ribosylation. Two magnesium ions flanked by highly conserved amino acids pinpoint the active-site crevice. Recombinant hARH3 binds free ADP-ribose with micromolar affinity and efficiently de-ADP-ribosylates poly- but not monoADP-ribosylated proteins. Docking experiments indicate a possible binding mode for ADP-ribose polymers and suggest a reaction mechanism. Our results underscore the importance of endogenous ADP-ribosylation cycles and provide a basis for structure-based design of ADP-ribosylhydrolase inhibitors.Proceedings of the National Academy of Sciences 11/2006; 103(41):15026-31. · 9.68 Impact Factor -
Article: Cloning, expression, purification, crystallization and preliminary X-ray diffraction analysis of human ARH3, the first eukaryotic protein-ADP-ribosylhydrolase.
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ABSTRACT: ADP-ribosylhydrolases catalyze the release of ADP-ribose from ADP-ribosylated proteins via hydrolysis of the glycosidic bond between ADP-ribose and a specific amino-acid residue in a target protein. Human ADP-ribosylhydrolase 3, consisting of 347 amino-acid residues, has been cloned and heterologously expressed in Escherichia coli, purified and crystallized in two different space groups. Preliminary X-ray diffraction studies yielded excellent diffraction data to a resolution of 1.6 A.Acta Crystallographica Section F Structural Biology and Crystallization Communications 04/2006; 62(Pt 3):224-7. · 0.51 Impact Factor -
Article: On the routine use of soft X-rays in macromolecular crystallography. Part III. The optimal data-collection wavelength.
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ABSTRACT: Complete and highly redundant data sets were collected at different wavelengths between 0.80 and 2.65 A for a total of ten different protein and DNA model systems. The magnitude of the anomalous signal-to-noise ratio as assessed by the quotient R(anom)/R(r.i.m.) was found to be influenced by the data-collection wavelength and the nature of the anomalously scattering substructure. By utilizing simple empirical correlations, for instance between the estimated deltaF/F and the expected R(anom) or the data-collection wavelength and the expected R(r.i.m.), the wavelength at which the highest anomalous signal-to-noise ratio can be expected could be estimated even before the experiment. Almost independent of the nature of the anomalously scattering substructure and provided that no elemental X-ray absorption edge is nearby, this optimal wavelength is 2.1 A.Acta Crystallographica Section D Biological Crystallography 10/2005; 61(Pt 9):1263-72. · 12.62 Impact Factor -
Article: Cloning, expression, purification, crystallization and preliminary X-ray diffraction analysis of DapB (Rv2773c) from Mycobacterium tuberculosis.
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ABSTRACT: Dihydrodipicolinate reductase from Mycobacterium tuberculosis (DapB, DHDPR, Rv2773c) has been cloned and heterologously expressed in Escherichia coli, purified using standard chromatographic techniques and crystallized in three different crystal forms. Preliminary diffraction data analysis suggests the presence of two tetramers in the asymmetric unit of one crystal form and half a tetramer in the other two crystal forms.Acta Crystallographica Section F Structural Biology and Crystallization Communications 08/2005; 61(Pt 7):718-21. · 0.51 Impact Factor -
Article: On the influence of the incident photon energy on the radiation damage in crystalline biological samples.
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ABSTRACT: Two series of complete and highly redundant data sets were collected at wavelengths of 1.00 and 2.00 Angstroms on a cadmium derivative of porcine pancreatic elastase (PPE). Radiation damage to the sample was evaluated qualitatively by inspecting consecutive difference electron density maps during the course of the experiment. The nature of the radiation damage was found to be identical at both wavelengths and was localized primarily at the four disulfide bridges of PPE, the cadmium site and the two methionine residues. For a quantitative examination of the radiation damage, the decrease in the peak height of the cadmium ion in various electron density maps was exploited. Again, no significant difference in radiation damage between the two wavelengths was observed. This can be rationalized by considering the wavelength dependencies of the number of diffracted photons versus the number of absorbed photons and the energy deposited in the crystal by the latter.Journal of Synchrotron Radiation 06/2005; 12(Pt 3):304-9. · 2.73 Impact Factor -
Article: The high-resolution Structure of LeuB (Rv2995c) from Mycobacterium tuberculosis.
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ABSTRACT: The crystal structure of the enzyme 3-isopropylmalate dehydrogenase (IPMDH) from Mycobacterium tuberculosis (LeuB, Mtb-IPMDH, Rv2995c) without substrate or co-factor was determined at 1.65 A resolution, which is the highest resolution reported for an IPMDH to date. The crystals contain two functional dimers in the asymmetric unit in an arrangement close to a tetramer of D2 symmetry. Despite the absence of a substrate or inhibitor bound to the protein, the structure of the monomer resembles the previously observed closed form of the enzyme more closely than the open form. A comparison with the substrate complex of IPMDH from Thiobacillus ferrooxidans and the co-factor complex of the Thermus thermophilus enzyme revealed a close relationship of the active-site architecture between the various bacterial enzymes. The inhibitor O-isobutenyl oxalylhydroxamate was found to bind to the active site of IPMDH in a mode similar to the substrate isopropylmalate.Journal of Molecular Biology 03/2005; 346(1):1-11. · 4.00 Impact Factor -
Article: On the routine use of soft X-rays in macromolecular crystallography. Part II. Data-collection wavelength and scaling models.
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ABSTRACT: Complete and highly redundant data sets were collected at nine different wavelengths between 0.80 and 2.65 A on a xenon derivative of porcine pancreatic elastase in both air and helium atmospheres. The magnitude of the anomalous signal, as assessed by the xenon-peak height in the anomalous difference Patterson synthesis, is affected by the wavelength of data collection as well as by the scaling model used. For data collected at wavelengths longer than 1.7 A, the use of a three-dimensional scaling protocol is essential in order to obtain the highest possible anomalous signal. Based on the scaling protocols currently available, the optimal wavelength range for data collection appears to be between 2.1 and 2.4 A. Beyond that, any further increase in signal will be compensated for or even superseded by a concomitant increase in noise, which cannot be fully corrected for. Data collection in a helium atmosphere yields higher I/sigma(I) values, but not significantly better anomalous differences, than data collection in air.Acta Crystallographica Section D Biological Crystallography 02/2004; 60(Pt 1):28-38. · 12.62 Impact Factor
Top co-authors
Top Journals
Institutions
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2012
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European Synchrotron Radiation Facility
Grenoble, Rhone-Alpes, France
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2006–2009
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Universität Hamburg
- Department of Immunology
Hamburg, Hamburg, Germany
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2002
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Universität Freiburg
- Institute of Organic Chemistry and Biochemistry (Organic Chemistry)
Freiburg, Lower Saxony, Germany
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