Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Publication Date: 2014-11-14
    Description: Topology, with its abstract mathematical constructs, often manifests itself in physics and has a pivotal role in our understanding of natural phenomena. Notably, the discovery of topological phases in condensed-matter systems has changed the modern conception of phases of matter. The global nature of topological ordering, however, makes direct experimental probing an outstanding challenge. Present experimental tools are mainly indirect and, as a result, are inadequate for studying the topology of physical systems at a fundamental level. Here we employ the exquisite control afforded by state-of-the-art superconducting quantum circuits to investigate topological properties of various quantum systems. The essence of our approach is to infer geometric curvature by measuring the deflection of quantum trajectories in the curved space of the Hamiltonian. Topological properties are then revealed by integrating the curvature over closed surfaces, a quantum analogue of the Gauss-Bonnet theorem. We benchmark our technique by investigating basic topological concepts of the historically important Haldane model after mapping the momentum space of this condensed-matter model to the parameter space of a single-qubit Hamiltonian. In addition to constructing the topological phase diagram, we are able to visualize the microscopic spin texture of the associated states and their evolution across a topological phase transition. Going beyond non-interacting systems, we demonstrate the power of our method by studying topology in an interacting quantum system. This required a new qubit architecture that allows for simultaneous control over every term in a two-qubit Hamiltonian. By exploring the parameter space of this Hamiltonian, we discover the emergence of an interaction-induced topological phase. Our work establishes a powerful, generalizable experimental platform to study topological phenomena in quantum systems.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Roushan, P -- Neill, C -- Chen, Yu -- Kolodrubetz, M -- Quintana, C -- Leung, N -- Fang, M -- Barends, R -- Campbell, B -- Chen, Z -- Chiaro, B -- Dunsworth, A -- Jeffrey, E -- Kelly, J -- Megrant, A -- Mutus, J -- O'Malley, P J J -- Sank, D -- Vainsencher, A -- Wenner, J -- White, T -- Polkovnikov, A -- Cleland, A N -- Martinis, J M -- England -- Nature. 2014 Nov 13;515(7526):241-4. doi: 10.1038/nature13891.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Department of Physics, University of California, Santa Barbara, California 93106-9530, USA. ; Department of Physics, Boston University, Boston, Massachusetts 02215, USA. ; 1] Department of Physics, University of California, Santa Barbara, California 93106-9530, USA [2] Google Inc., Santa Barbara, California 93117, USA.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/25391961" target="_blank"〉PubMed〈/a〉
    Print ISSN: 0028-0836
    Electronic ISSN: 1476-4687
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
    Signatur Availability
    BibTip Others were also interested in ...
  • 2
    Publication Date: 2012-06-02
    Description: Structure determination of proteins and other macromolecules has historically required the growth of high-quality crystals sufficiently large to diffract x-rays efficiently while withstanding radiation damage. We applied serial femtosecond crystallography (SFX) using an x-ray free-electron laser (XFEL) to obtain high-resolution structural information from microcrystals (less than 1 micrometer by 1 micrometer by 3 micrometers) of the well-characterized model protein lysozyme. The agreement with synchrotron data demonstrates the immediate relevance of SFX for analyzing the structure of the large group of difficult-to-crystallize molecules.〈br /〉〈br /〉〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3788707/" target="_blank"〉〈img src="https://static.pubmed.gov/portal/portal3rc.fcgi/4089621/img/3977009" border="0"〉〈/a〉   〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3788707/" target="_blank"〉This paper as free author manuscript - peer-reviewed and accepted for publication〈/a〉〈br /〉〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Boutet, Sebastien -- Lomb, Lukas -- Williams, Garth J -- Barends, Thomas R M -- Aquila, Andrew -- Doak, R Bruce -- Weierstall, Uwe -- DePonte, Daniel P -- Steinbrener, Jan -- Shoeman, Robert L -- Messerschmidt, Marc -- Barty, Anton -- White, Thomas A -- Kassemeyer, Stephan -- Kirian, Richard A -- Seibert, M Marvin -- Montanez, Paul A -- Kenney, Chris -- Herbst, Ryan -- Hart, Philip -- Pines, Jack -- Haller, Gunther -- Gruner, Sol M -- Philipp, Hugh T -- Tate, Mark W -- Hromalik, Marianne -- Koerner, Lucas J -- van Bakel, Niels -- Morse, John -- Ghonsalves, Wilfred -- Arnlund, David -- Bogan, Michael J -- Caleman, Carl -- Fromme, Raimund -- Hampton, Christina Y -- Hunter, Mark S -- Johansson, Linda C -- Katona, Gergely -- Kupitz, Christopher -- Liang, Mengning -- Martin, Andrew V -- Nass, Karol -- Redecke, Lars -- Stellato, Francesco -- Timneanu, Nicusor -- Wang, Dingjie -- Zatsepin, Nadia A -- Schafer, Donald -- Defever, James -- Neutze, Richard -- Fromme, Petra -- Spence, John C H -- Chapman, Henry N -- Schlichting, Ilme -- 1R01GM095583/GM/NIGMS NIH HHS/ -- R01 GM095583/GM/NIGMS NIH HHS/ -- New York, N.Y. -- Science. 2012 Jul 20;337(6092):362-4. doi: 10.1126/science.1217737. Epub 2012 May 31.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Linac Coherent Light Source, SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, CA 94025, USA. sboutet@slac.stanford.edu〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/22653729" target="_blank"〉PubMed〈/a〉
    Keywords: Animals ; Crystallography, X-Ray/*methods ; Lasers ; Muramidase/chemistry/radiation effects ; *Protein Conformation
    Print ISSN: 0036-8075
    Electronic ISSN: 1095-9203
    Topics: Biology , Chemistry and Pharmacology , Computer Science , Medicine , Natural Sciences in General , Physics
    Signatur Availability
    BibTip Others were also interested in ...
  • 3
    Publication Date: 2011-10-21
    Description: Extremophilic organisms require specialized enzymes for their exotic metabolisms. Acid-loving thermophilic Archaea that live in the mudpots of volcanic solfataras obtain their energy from reduced sulphur compounds such as hydrogen sulphide (H(2)S) and carbon disulphide (CS(2)). The oxidation of these compounds into sulphuric acid creates the extremely acidic environment that characterizes solfataras. The hyperthermophilic Acidianus strain A1-3, which was isolated from the fumarolic, ancient sauna building at the Solfatara volcano (Naples, Italy), was shown to rapidly convert CS(2) into H(2)S and carbon dioxide (CO(2)), but nothing has been known about the modes of action and the evolution of the enzyme(s) involved. Here we describe the structure, the proposed mechanism and evolution of a CS(2) hydrolase from Acidianus A1-3. The enzyme monomer displays a typical beta-carbonic anhydrase fold and active site, yet CO(2) is not one of its substrates. Owing to large carboxy- and amino-terminal arms, an unusual hexadecameric catenane oligomer has evolved. This structure results in the blocking of the entrance to the active site that is found in canonical beta-carbonic anhydrases and the formation of a single 15-A-long, highly hydrophobic tunnel that functions as a specificity filter. The tunnel determines the enzyme's substrate specificity for CS(2), which is hydrophobic. The transposon sequences that surround the gene encoding this CS(2) hydrolase point to horizontal gene transfer as a mechanism for its acquisition during evolution. Our results show how the ancient beta-carbonic anhydrase, which is central to global carbon metabolism, was transformed by divergent evolution into a crucial enzyme in CS(2) metabolism.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Smeulders, Marjan J -- Barends, Thomas R M -- Pol, Arjan -- Scherer, Anna -- Zandvoort, Marcel H -- Udvarhelyi, Aniko -- Khadem, Ahmad F -- Menzel, Andreas -- Hermans, John -- Shoeman, Robert L -- Wessels, Hans J C T -- van den Heuvel, Lambert P -- Russ, Lina -- Schlichting, Ilme -- Jetten, Mike S M -- Op den Camp, Huub J M -- England -- Nature. 2011 Oct 19;478(7369):412-6. doi: 10.1038/nature10464.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Department of Microbiology, Radboud University Nijmegen, Heyendaalseweg 135, 6525 AJ, Nijmegen, The Netherlands.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/22012399" target="_blank"〉PubMed〈/a〉
    Keywords: Acidianus/classification/*enzymology/genetics ; Carbon Disulfide/*metabolism ; Catalytic Domain ; Crystallography, X-Ray ; *Evolution, Molecular ; Hydrolases/chemistry/*genetics ; Models, Molecular ; Molecular Sequence Data ; Mutation ; Phylogeny ; Protein Structure, Tertiary
    Print ISSN: 0028-0836
    Electronic ISSN: 1476-4687
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
    Signatur Availability
    BibTip Others were also interested in ...
  • 4
    Publication Date: 2013-11-26
    Description: The determination of protein crystal structures is hampered by the need for macroscopic crystals. X-ray free-electron lasers (FELs) provide extremely intense pulses of femtosecond duration, which allow data collection from nanometre- to micrometre-sized crystals in a 'diffraction-before-destruction' approach. So far, all protein structure determinations carried out using FELs have been based on previous knowledge of related, known structures. Here we show that X-ray FEL data can be used for de novo protein structure determination, that is, without previous knowledge about the structure. Using the emerging technique of serial femtosecond crystallography, we performed single-wavelength anomalous scattering measurements on microcrystals of the well-established model system lysozyme, in complex with a lanthanide compound. Using Monte-Carlo integration, we obtained high-quality diffraction intensities from which experimental phases could be determined, resulting in an experimental electron density map good enough for automated building of the protein structure. This demonstrates the feasibility of determining novel protein structures using FELs. We anticipate that serial femtosecond crystallography will become an important tool for the structure determination of proteins that are difficult to crystallize, such as membrane proteins.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Barends, Thomas R M -- Foucar, Lutz -- Botha, Sabine -- Doak, R Bruce -- Shoeman, Robert L -- Nass, Karol -- Koglin, Jason E -- Williams, Garth J -- Boutet, Sebastien -- Messerschmidt, Marc -- Schlichting, Ilme -- England -- Nature. 2014 Jan 9;505(7482):244-7. doi: 10.1038/nature12773. Epub 2013 Nov 24.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Max-Planck Institute for Medical Research, Jahnstrasse 29, D-69120 Heidelberg, Germany. ; 1] Max-Planck Institute for Medical Research, Jahnstrasse 29, D-69120 Heidelberg, Germany [2] Department of Physics, Arizona State University, PO Box 871504, Tempe, Arizona 85287-1504, USA. ; SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California 94025, USA.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/24270807" target="_blank"〉PubMed〈/a〉
    Keywords: Animals ; Chickens ; Crystallization ; Crystallography/*methods ; *Electrons ; Female ; Gadolinium ; *Lasers ; Membrane Proteins/chemistry ; Models, Molecular ; Monte Carlo Method ; Muramidase/chemistry ; Protein Conformation ; Proteins/*chemistry ; Time Factors ; X-Ray Diffraction/*methods ; *X-Rays
    Print ISSN: 0028-0836
    Electronic ISSN: 1476-4687
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
    Signatur Availability
    BibTip Others were also interested in ...
  • 5
    Publication Date: 2011-02-05
    Description: X-ray crystallography provides the vast majority of macromolecular structures, but the success of the method relies on growing crystals of sufficient size. In conventional measurements, the necessary increase in X-ray dose to record data from crystals that are too small leads to extensive damage before a diffraction signal can be recorded. It is particularly challenging to obtain large, well-diffracting crystals of membrane proteins, for which fewer than 300 unique structures have been determined despite their importance in all living cells. Here we present a method for structure determination where single-crystal X-ray diffraction 'snapshots' are collected from a fully hydrated stream of nanocrystals using femtosecond pulses from a hard-X-ray free-electron laser, the Linac Coherent Light Source. We prove this concept with nanocrystals of photosystem I, one of the largest membrane protein complexes. More than 3,000,000 diffraction patterns were collected in this study, and a three-dimensional data set was assembled from individual photosystem I nanocrystals ( approximately 200 nm to 2 mum in size). We mitigate the problem of radiation damage in crystallography by using pulses briefer than the timescale of most damage processes. This offers a new approach to structure determination of macromolecules that do not yield crystals of sufficient size for studies using conventional radiation sources or are particularly sensitive to radiation damage.〈br /〉〈br /〉〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3429598/" target="_blank"〉〈img src="https://static.pubmed.gov/portal/portal3rc.fcgi/4089621/img/3977009" border="0"〉〈/a〉   〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3429598/" target="_blank"〉This paper as free author manuscript - peer-reviewed and accepted for publication〈/a〉〈br /〉〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Chapman, Henry N -- Fromme, Petra -- Barty, Anton -- White, Thomas A -- Kirian, Richard A -- Aquila, Andrew -- Hunter, Mark S -- Schulz, Joachim -- DePonte, Daniel P -- Weierstall, Uwe -- Doak, R Bruce -- Maia, Filipe R N C -- Martin, Andrew V -- Schlichting, Ilme -- Lomb, Lukas -- Coppola, Nicola -- Shoeman, Robert L -- Epp, Sascha W -- Hartmann, Robert -- Rolles, Daniel -- Rudenko, Artem -- Foucar, Lutz -- Kimmel, Nils -- Weidenspointner, Georg -- Holl, Peter -- Liang, Mengning -- Barthelmess, Miriam -- Caleman, Carl -- Boutet, Sebastien -- Bogan, Michael J -- Krzywinski, Jacek -- Bostedt, Christoph -- Bajt, Sasa -- Gumprecht, Lars -- Rudek, Benedikt -- Erk, Benjamin -- Schmidt, Carlo -- Homke, Andre -- Reich, Christian -- Pietschner, Daniel -- Struder, Lothar -- Hauser, Gunter -- Gorke, Hubert -- Ullrich, Joachim -- Herrmann, Sven -- Schaller, Gerhard -- Schopper, Florian -- Soltau, Heike -- Kuhnel, Kai-Uwe -- Messerschmidt, Marc -- Bozek, John D -- Hau-Riege, Stefan P -- Frank, Matthias -- Hampton, Christina Y -- Sierra, Raymond G -- Starodub, Dmitri -- Williams, Garth J -- Hajdu, Janos -- Timneanu, Nicusor -- Seibert, M Marvin -- Andreasson, Jakob -- Rocker, Andrea -- Jonsson, Olof -- Svenda, Martin -- Stern, Stephan -- Nass, Karol -- Andritschke, Robert -- Schroter, Claus-Dieter -- Krasniqi, Faton -- Bott, Mario -- Schmidt, Kevin E -- Wang, Xiaoyu -- Grotjohann, Ingo -- Holton, James M -- Barends, Thomas R M -- Neutze, Richard -- Marchesini, Stefano -- Fromme, Raimund -- Schorb, Sebastian -- Rupp, Daniela -- Adolph, Marcus -- Gorkhover, Tais -- Andersson, Inger -- Hirsemann, Helmut -- Potdevin, Guillaume -- Graafsma, Heinz -- Nilsson, Bjorn -- Spence, John C H -- 1R01GM095583-01/GM/NIGMS NIH HHS/ -- 1U54GM094625-01/GM/NIGMS NIH HHS/ -- R01 GM095583/GM/NIGMS NIH HHS/ -- U54 GM094599/GM/NIGMS NIH HHS/ -- U54 GM094625/GM/NIGMS NIH HHS/ -- England -- Nature. 2011 Feb 3;470(7332):73-7. doi: 10.1038/nature09750.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Center for Free-Electron Laser Science, DESY, Notkestrasse 85, 22607 Hamburg, Germany. henry.chapman@desy.de〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/21293373" target="_blank"〉PubMed〈/a〉
    Keywords: Crystallography, X-Ray/instrumentation/*methods ; Lasers ; Models, Molecular ; Nanoparticles/*chemistry ; Nanotechnology/instrumentation/*methods ; Photosystem I Protein Complex/*chemistry ; Protein Conformation ; Time Factors ; X-Rays
    Print ISSN: 0028-0836
    Electronic ISSN: 1476-4687
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
    Signatur Availability
    BibTip Others were also interested in ...
  • 6
    Publication Date: 2014-04-25
    Description: A quantum computer can solve hard problems, such as prime factoring, database searching and quantum simulation, at the cost of needing to protect fragile quantum states from error. Quantum error correction provides this protection by distributing a logical state among many physical quantum bits (qubits) by means of quantum entanglement. Superconductivity is a useful phenomenon in this regard, because it allows the construction of large quantum circuits and is compatible with microfabrication. For superconducting qubits, the surface code approach to quantum computing is a natural choice for error correction, because it uses only nearest-neighbour coupling and rapidly cycled entangling gates. The gate fidelity requirements are modest: the per-step fidelity threshold is only about 99 per cent. Here we demonstrate a universal set of logic gates in a superconducting multi-qubit processor, achieving an average single-qubit gate fidelity of 99.92 per cent and a two-qubit gate fidelity of up to 99.4 per cent. This places Josephson quantum computing at the fault-tolerance threshold for surface code error correction. Our quantum processor is a first step towards the surface code, using five qubits arranged in a linear array with nearest-neighbour coupling. As a further demonstration, we construct a five-qubit Greenberger-Horne-Zeilinger state using the complete circuit and full set of gates. The results demonstrate that Josephson quantum computing is a high-fidelity technology, with a clear path to scaling up to large-scale, fault-tolerant quantum circuits.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Barends, R -- Kelly, J -- Megrant, A -- Veitia, A -- Sank, D -- Jeffrey, E -- White, T C -- Mutus, J -- Fowler, A G -- Campbell, B -- Chen, Y -- Chen, Z -- Chiaro, B -- Dunsworth, A -- Neill, C -- O'Malley, P -- Roushan, P -- Vainsencher, A -- Wenner, J -- Korotkov, A N -- Cleland, A N -- Martinis, John M -- England -- Nature. 2014 Apr 24;508(7497):500-3. doi: 10.1038/nature13171.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉1] Department of Physics, University of California, Santa Barbara, California 93106, USA [2]. ; Department of Physics, University of California, Santa Barbara, California 93106, USA. ; Department of Electrical Engineering, University of California, Riverside, California 92521, USA. ; 1] Department of Physics, University of California, Santa Barbara, California 93106, USA [2] Centre for Quantum Computation and Communication Technology, School of Physics, The University of Melbourne, Victoria 3010, Australia.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/24759412" target="_blank"〉PubMed〈/a〉
    Print ISSN: 0028-0836
    Electronic ISSN: 1476-4687
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
    Signatur Availability
    BibTip Others were also interested in ...
  • 7
    Publication Date: 2015-03-06
    Description: Quantum computing becomes viable when a quantum state can be protected from environment-induced error. If quantum bits (qubits) are sufficiently reliable, errors are sparse and quantum error correction (QEC) is capable of identifying and correcting them. Adding more qubits improves the preservation of states by guaranteeing that increasingly larger clusters of errors will not cause logical failure-a key requirement for large-scale systems. Using QEC to extend the qubit lifetime remains one of the outstanding experimental challenges in quantum computing. Here we report the protection of classical states from environmental bit-flip errors and demonstrate the suppression of these errors with increasing system size. We use a linear array of nine qubits, which is a natural step towards the two-dimensional surface code QEC scheme, and track errors as they occur by repeatedly performing projective quantum non-demolition parity measurements. Relative to a single physical qubit, we reduce the failure rate in retrieving an input state by a factor of 2.7 when using five of our nine qubits and by a factor of 8.5 when using all nine qubits after eight cycles. Additionally, we tomographically verify preservation of the non-classical Greenberger-Horne-Zeilinger state. The successful suppression of environment-induced errors will motivate further research into the many challenges associated with building a large-scale superconducting quantum computer.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Kelly, J -- Barends, R -- Fowler, A G -- Megrant, A -- Jeffrey, E -- White, T C -- Sank, D -- Mutus, J Y -- Campbell, B -- Chen, Yu -- Chen, Z -- Chiaro, B -- Dunsworth, A -- Hoi, I-C -- Neill, C -- O'Malley, P J J -- Quintana, C -- Roushan, P -- Vainsencher, A -- Wenner, J -- Cleland, A N -- Martinis, John M -- England -- Nature. 2015 Mar 5;519(7541):66-9. doi: 10.1038/nature14270.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Department of Physics, University of California, Santa Barbara, California 93106, USA. ; 1] Department of Physics, University of California, Santa Barbara, California 93106, USA [2] Centre for Quantum Computation and Communication Technology, School of Physics, The University of Melbourne, Victoria 3010, Australia. ; 1] Department of Physics, University of California, Santa Barbara, California 93106, USA [2] Department of Materials, University of California, Santa Barbara, California 93106, USA.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/25739628" target="_blank"〉PubMed〈/a〉
    Print ISSN: 0028-0836
    Electronic ISSN: 1476-4687
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
    Signatur Availability
    BibTip Others were also interested in ...
  • 8
    Publication Date: 2015-10-20
    Description: Anaerobic ammonium oxidation (anammox) has a major role in the Earth's nitrogen cycle and is used in energy-efficient wastewater treatment. This bacterial process combines nitrite and ammonium to form dinitrogen (N2) gas, and has been estimated to synthesize up to 50% of the dinitrogen gas emitted into our atmosphere from the oceans. Strikingly, the anammox process relies on the highly unusual, extremely reactive intermediate hydrazine, a compound also used as a rocket fuel because of its high reducing power. So far, the enzymatic mechanism by which hydrazine is synthesized is unknown. Here we report the 2.7 A resolution crystal structure, as well as biophysical and spectroscopic studies, of a hydrazine synthase multiprotein complex isolated from the anammox organism Kuenenia stuttgartiensis. The structure shows an elongated dimer of heterotrimers, each of which has two unique c-type haem-containing active sites, as well as an interaction point for a redox partner. Furthermore, a system of tunnels connects these active sites. The crystal structure implies a two-step mechanism for hydrazine synthesis: a three-electron reduction of nitric oxide to hydroxylamine at the active site of the gamma-subunit and its subsequent condensation with ammonia, yielding hydrazine in the active centre of the alpha-subunit. Our results provide the first, to our knowledge, detailed structural insight into the mechanism of biological hydrazine synthesis, which is of major significance for our understanding of the conversion of nitrogenous compounds in nature.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Dietl, Andreas -- Ferousi, Christina -- Maalcke, Wouter J -- Menzel, Andreas -- de Vries, Simon -- Keltjens, Jan T -- Jetten, Mike S M -- Kartal, Boran -- Barends, Thomas R M -- P41-GM103311/GM/NIGMS NIH HHS/ -- England -- Nature. 2015 Nov 19;527(7578):394-7. doi: 10.1038/nature15517. Epub 2015 Oct 19.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Department of Biomolecular Mechanisms, Max Planck Institute for Medical Research, 69120 Heidelberg, Germany. ; Department of Microbiology, Institute for Water and Wetland Research, Radboud University Nijmegen, 6525 AJ Nijmegen, The Netherlands. ; Swiss Light Source, Paul Scherrer Institute, 5232 Villigen, Switzerland. ; Department of Biotechnology, Delft University of Technology, Delft, The Netherlands. ; Department of Biochemistry and Microbiology, Laboratory of Microbiology, Gent University, Gent, Belgium.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/26479033" target="_blank"〉PubMed〈/a〉
    Keywords: Bacteria/*enzymology ; Catalytic Domain ; Crystallography, X-Ray ; Hydrazines/*metabolism ; Hydroxylamine/metabolism ; Metalloproteins/chemistry/metabolism ; Models, Molecular ; Multienzyme Complexes/*chemistry/*metabolism ; Nitric Oxide/metabolism ; Protein Multimerization
    Print ISSN: 0028-0836
    Electronic ISSN: 1476-4687
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
    Signatur Availability
    BibTip Others were also interested in ...
  • 9
    Publication Date: 2012-12-01
    Description: The Trypanosoma brucei cysteine protease cathepsin B (TbCatB), which is involved in host protein degradation, is a promising target to develop new treatments against sleeping sickness, a fatal disease caused by this protozoan parasite. The structure of the mature, active form of TbCatB has so far not provided sufficient information for the design of a safe and specific drug against T. brucei. By combining two recent innovations, in vivo crystallization and serial femtosecond crystallography, we obtained the room-temperature 2.1 angstrom resolution structure of the fully glycosylated precursor complex of TbCatB. The structure reveals the mechanism of native TbCatB inhibition and demonstrates that new biomolecular information can be obtained by the "diffraction-before-destruction" approach of x-ray free-electron lasers from hundreds of thousands of individual microcrystals.〈br /〉〈br /〉〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3786669/" target="_blank"〉〈img src="https://static.pubmed.gov/portal/portal3rc.fcgi/4089621/img/3977009" border="0"〉〈/a〉   〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3786669/" target="_blank"〉This paper as free author manuscript - peer-reviewed and accepted for publication〈/a〉〈br /〉〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Redecke, Lars -- Nass, Karol -- DePonte, Daniel P -- White, Thomas A -- Rehders, Dirk -- Barty, Anton -- Stellato, Francesco -- Liang, Mengning -- Barends, Thomas R M -- Boutet, Sebastien -- Williams, Garth J -- Messerschmidt, Marc -- Seibert, M Marvin -- Aquila, Andrew -- Arnlund, David -- Bajt, Sasa -- Barth, Torsten -- Bogan, Michael J -- Caleman, Carl -- Chao, Tzu-Chiao -- Doak, R Bruce -- Fleckenstein, Holger -- Frank, Matthias -- Fromme, Raimund -- Galli, Lorenzo -- Grotjohann, Ingo -- Hunter, Mark S -- Johansson, Linda C -- Kassemeyer, Stephan -- Katona, Gergely -- Kirian, Richard A -- Koopmann, Rudolf -- Kupitz, Chris -- Lomb, Lukas -- Martin, Andrew V -- Mogk, Stefan -- Neutze, Richard -- Shoeman, Robert L -- Steinbrener, Jan -- Timneanu, Nicusor -- Wang, Dingjie -- Weierstall, Uwe -- Zatsepin, Nadia A -- Spence, John C H -- Fromme, Petra -- Schlichting, Ilme -- Duszenko, Michael -- Betzel, Christian -- Chapman, Henry N -- 1R01GM095583/GM/NIGMS NIH HHS/ -- R01 GM095583/GM/NIGMS NIH HHS/ -- U54 GM094599/GM/NIGMS NIH HHS/ -- New York, N.Y. -- Science. 2013 Jan 11;339(6116):227-30. doi: 10.1126/science.1229663. Epub 2012 Nov 29.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Joint Laboratory for Structural Biology of Infection and Inflammation, Institute of Biochemistry and Molecular Biology, University of Hamburg, and Institute of Biochemistry, University of Lubeck, at Deutsches Elektronen-Synchrotron, Notkestrasse 85, 22607 Hamburg, Germany.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/23196907" target="_blank"〉PubMed〈/a〉
    Keywords: Amino Acid Sequence ; Animals ; Catalytic Domain ; Cathepsin B/antagonists & inhibitors/*chemistry ; Crystallization ; Crystallography, X-Ray ; Enzyme Precursors/chemistry ; Glycosylation ; Models, Molecular ; Molecular Sequence Data ; Protein Conformation ; Protozoan Proteins/antagonists & inhibitors/*chemistry ; Sf9 Cells ; Spodoptera ; Trypanosoma brucei brucei/*enzymology ; X-Rays
    Print ISSN: 0036-8075
    Electronic ISSN: 1095-9203
    Topics: Biology , Chemistry and Pharmacology , Computer Science , Medicine , Natural Sciences in General , Physics
    Signatur Availability
    BibTip Others were also interested in ...
  • 10
    Publication Date: 2015-09-12
    Description: The hemoprotein myoglobin is a model system for the study of protein dynamics. We used time-resolved serial femtosecond crystallography at an x-ray free-electron laser to resolve the ultrafast structural changes in the carbonmonoxy myoglobin complex upon photolysis of the Fe-CO bond. Structural changes appear throughout the protein within 500 femtoseconds, with the C, F, and H helices moving away from the heme cofactor and the E and A helices moving toward it. These collective movements are predicted by hybrid quantum mechanics/molecular mechanics simulations. Together with the observed oscillations of residues contacting the heme, our calculations support the prediction that an immediate collective response of the protein occurs upon ligand dissociation, as a result of heme vibrational modes coupling to global modes of the protein.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Barends, Thomas R M -- Foucar, Lutz -- Ardevol, Albert -- Nass, Karol -- Aquila, Andrew -- Botha, Sabine -- Doak, R Bruce -- Falahati, Konstantin -- Hartmann, Elisabeth -- Hilpert, Mario -- Heinz, Marcel -- Hoffmann, Matthias C -- Kofinger, Jurgen -- Koglin, Jason E -- Kovacsova, Gabriela -- Liang, Mengning -- Milathianaki, Despina -- Lemke, Henrik T -- Reinstein, Jochen -- Roome, Christopher M -- Shoeman, Robert L -- Williams, Garth J -- Burghardt, Irene -- Hummer, Gerhard -- Boutet, Sebastien -- Schlichting, Ilme -- New York, N.Y. -- Science. 2015 Oct 23;350(6259):445-50. doi: 10.1126/science.aac5492. Epub 2015 Sep 10.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Max-Planck-Institut fur Medizinische Forschung, Jahnstrasse 29, 69120 Heidelberg, Germany. thomas.barends@mpimf-heidelberg.mpg.de ilme.schlichting@mpimf-heidelberg.mpg.de. ; Max-Planck-Institut fur Medizinische Forschung, Jahnstrasse 29, 69120 Heidelberg, Germany. ; Max-Planck-Institut fur Biophysik, Max-von-Laue-Strasse 3, 60438 Frankfurt am Main, Germany. ; European XFEL GmbH, Albert-Einstein-Ring 19, 22761 Hamburg, Germany. ; Institut fur Physikalische und Theoretische Chemie, Goethe-Universitat, Max-von-Laue-Strasse 7, 60438 Frankfurt am Main, Germany. ; Max-Planck-Institut fur Biophysik, Max-von-Laue-Strasse 3, 60438 Frankfurt am Main, Germany. Institut fur Physikalische und Theoretische Chemie, Goethe-Universitat, Max-von-Laue-Strasse 7, 60438 Frankfurt am Main, Germany. ; Linac Coherent Light Source (LCLS), SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, CA 94025, USA.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/26359336" target="_blank"〉PubMed〈/a〉
    Print ISSN: 0036-8075
    Electronic ISSN: 1095-9203
    Topics: Biology , Chemistry and Pharmacology , Computer Science , Medicine , Natural Sciences in General , Physics
    Signatur Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...