58 research outputs found
Discrete Three-dimensional Representation of Macromolecular Motion from eNOE-based Ensemble Calculation
Three-dimensional structural data and description of dynamics are fundamental to infer and understand protein function. Structure determination by NMR follows well-established protocols while NMR relaxation phenomena provide insights into local molecular dynamics. However, methods to
detect concerted motion were not pursued until very recently. Here, we present an ensemble-based structure determination protocol using ensemble-averaged distance restraints obtained from exact NOE (eNOE) rate constants. An application of our protocol to the model protein GB3 established an
ensemble of structures that reveals correlated motion across the ?-sheet and concerted motion between the backbone and side chains localized in the core. Furthermore, the data repudiate concerted conformational exchange between the ?-sheet and the ?-helix
Stereospecific assignments in proteins using exact NOEs
Recently developed methods to measure distances in proteins with high accuracy by "exactâ nuclear Overhauser effects (eNOEs) make it possible to determine stereospecific assignments, which are particularly important to fully exploit the accuracy of the eNOE distance measurements. Stereospecific assignments are determined by comparing the eNOE-derived distances to protein structure bundles calculated without stereospecific assignments, or an independently determined crystal structure. The absolute and relative CYANA target function difference upon swapping the stereospecific assignment of a diastereotopic group yields the respective stereospecific assignment. We applied the method to the eNOE data set that has recently been obtained for the third immunoglobulin-binding domain of protein G (GB3). The 884 eNOEs provide relevant data for 47 of the total of 75 diastereotopic groups. Stereospecific assignments could be established for 45 diastereotopic groups (96%) using the X-ray structure, or for 27 diastereotopic groups (57%) using structures calculated with the eNOE data set without stereospecific assignments, all of which are in agreement with those determined previously. The latter case is relevant for structure determinations based on eNOEs. The accuracy of the eNOE distance measurements is crucial for making stereospecific assignments because applying the same method to the traditional NOE data set for GB3 with imprecise upper distance bounds yields only 13 correct stereospecific assignments using the X-ray structure or 2 correct stereospecific assignments using NMR structures calculated without stereospecific assignment
Recent Advances
Although often depicted as rigid structures, proteins are highly dynamic
systems, whose motions are essential to their functions. Despite this, it is
difficult to investigate protein dynamics due to the rapid timescale at which
they sample their conformational space, leading most NMR-determined structures
to represent only an averaged snapshot of the dynamic picture. While NMR
relaxation measurements can help to determine local dynamics, it is difficult
to detect translational or concerted motion, and only recently have
significant advances been made to make it possible to acquire a more holistic
representation of the dynamics and structural landscapes of proteins. Here, we
briefly revisit our most recent progress in the theory and use of exact
nuclear Overhauser enhancements (eNOEs) for the calculation of structural
ensembles that describe their conformational space. New developments are
primarily targeted at increasing the number and improving the quality of
extracted eNOE distance restraints, such that the multi-state structure
calculation can be applied to proteins of higher molecular weights. We then
review the implications of the exact NOE to the protein dynamics and function
of cyclophilin A and the WW domain of Pin1, and finally discuss our current
research and future directions
An NMR-based scoring function improves the accuracy of binding pose predictions by docking by two orders of magnitude
Low-affinity ligands can be efficiently optimized into high-affinity drug leads by structure based drug design when atomic-resolution structural information on the protein/ligand complexes is available. In this work we show that the use of a few, easily obtainable, experimental restraints improves the accuracy of the docking experiments by two orders of magnitude. The experimental data are measured in nuclear magnetic resonance spectra and consist of protein-mediated NOEs between two competitively binding ligands. The methodology can be widely applied as the data are readily obtained for low-affinity ligands in the presence of non-labelled receptor at low concentration. The experimental inter-ligand NOEs are efficiently used to filter and rank complex model structures that have been pre-selected by docking protocols. This approach dramatically reduces the degeneracy and inaccuracy of the chosen model in docking experiments, is robust with respect to inaccuracy of the structural model used to represent the free receptor and is suitable for high-throughput docking campaigns
Comprehensive Fragment Screening of the SARS-CoV-2 Proteome Explores Novel Chemical Space for Drug Development
12 pags., 4 figs., 3 tabs.SARS-CoV-2 (SCoV2) and its variants of concern pose serious challenges to the public health. The variants increased challenges to vaccines, thus necessitating for development of new intervention strategies including anti-virals. Within the international Covid19-NMR consortium, we have identified binders targeting the RNA genome of SCoV2. We established protocols for the production and NMR characterization of more than 80â% of all SCoV2 proteins. Here, we performed an NMR screening using a fragment library for binding to 25 SCoV2 proteins and identified hits also against previously unexplored SCoV2 proteins. Computational mapping was used to predict binding sites and identify functional moieties (chemotypes) of the ligands occupying these pockets. Striking consensus was observed between NMR-detected binding sites of the main protease and the computational procedure. Our investigation provides novel structural and chemical space for structure-based drug design against the SCoV2 proteome.Work at BMRZ is supported by the state of Hesse. Work in Covid19-NMR
was supported by the Goethe Corona Funds, by the IWBEFRE-program 20007375 of state of Hesse, the DFG
through CRC902: âMolecular Principles of RNA-based regulation.â and through infrastructure funds (project
numbers: 277478796, 277479031, 392682309, 452632086, 70653611) and by European Unionâs Horizon 2020 research and innovation program iNEXT-discovery under grant agreement No 871037. BY-COVID receives funding from the European Unionâs Horizon Europe Research and Innovation Programme under grant agreement number 101046203. âINSPIREDâ (MIS 5002550) project, implemented under the Action âReinforcement of the Research and Innovation Infrastructure,â funded by the Operational
Program âCompetitiveness, Entrepreneurship and Innovationâ (NSRF 2014â2020) and co-financed by Greece and the EU (European Regional Development Fund) and the FP7 REGPOT CT-2011-285950ââSEE-DRUGâ project (purchase of UPATâs 700 MHz NMR equipment). The support of the CERM/CIRMMP center of Instruct-ERIC is gratefully acknowledged. This work has been funded in part by a grant of the Italian Ministry of University and Research (FISR2020IP_02112, ID-COVID) and by Fondazione CR
Firenze. A.S. is supported by the Deutsche Forschungsgemeinschaft [SFB902/B16, SCHL2062/2-1] and the Johanna Quandt Young Academy at Goethe [2019/AS01]. M.H. and C.F. thank SFB902 and the Stiftung Polytechnische Gesellschaft for the Scholarship. L.L. work was supported by the French National Research Agency (ANR, NMR-SCoV2-ORF8), the Fondation de la Recherche MĂ©dicale (FRM, NMR-SCoV2-ORF8), FINOVI and the IR-RMN-THC Fr3050 CNRS. Work at UConn Health was supported by grants from the US National Institutes of Health (R01 GM135592 to B.H., P41 GM111135 and R01 GM123249 to J.C.H.) and the US National Science Foundation (DBI 2030601 to J.C.H.). Latvian Council of Science Grant No. VPP-COVID-2020/1-0014. National Science Foundation EAGER MCB-2031269. This work was supported by the grant Krebsliga KFS-4903-08-2019 and SNF-311030_192646 to J.O. P.G. (ITMP) The EOSC Future project is co-funded by the European Union Horizon Programme call INFRAEOSC-03-2020âGrant Agreement
Number 101017536. Open Access funding enabled and organized by Projekt DEALPeer reviewe
Large-Scale Recombinant Production of the SARS-CoV-2 Proteome for High-Throughput and Structural Biology Applications
The highly infectious disease COVID-19 caused by the Betacoronavirus SARS-CoV-2 poses a severe threat to humanity and demands the redirection of scientific efforts and criteria to organized research projects. The international COVID19-NMR consortium seeks to provide such new approaches by gathering scientific expertise worldwide. In particular, making available viral proteins and RNAs will pave the way to understanding the SARS-CoV-2 molecular components in detail. The research in COVID19-NMR and the resources provided through the consortium are fully disclosed to accelerate access and exploitation. NMR investigations of the viral molecular components are designated to provide the essential basis for further work, including macromolecular interaction studies and high-throughput drug screening. Here, we present the extensive catalog of a holistic SARS-CoV-2 protein preparation approach based on the consortiumâs collective efforts. We provide protocols for the large-scale production of more than 80% of all SARS-CoV-2 proteins or essential parts of them. Several of the proteins were produced in more than one laboratory, demonstrating the high interoperability between NMR groups worldwide. For the majority of proteins, we can produce isotope-labeled samples of HSQC-grade. Together with several NMR chemical shift assignments made publicly available on covid19-nmr.com, we here provide highly valuable resources for the production of SARS-CoV-2 proteins in isotope-labeled form
NMR2: A highly accurate approach to protein-ligand binding
A novel method to determine accurately and efficiently the structure of the receptor binding sites in protein-ligand complexes promises to revolutionize drug discovery. Dr Julien Orts and his collaborators at the Swiss Federal Institute of Technology are developing a powerful and general technique, based on liquid nuclear magnetic resonance (NMR), to shed light on the details of how proteins interact with drugs
Caractérisation des interactions entre ligands et protéines par RMN en solution
Submitted in March 2010 to The Faculty of Physics of the University Joseph Fourier Grenoble, France and The European Molecular Biology Laboratory Heidelberg, GermanyUn des buts de la recherche pharmaceutique est l'inhibition de protĂ©ines avec l'aide de petites molĂ©cules (ligands). L'une des phases clefs de ce procĂ©dĂ© est la dĂ©termination du mode d'interaction entre un ligand et son rĂ©cepteur. Cette tĂąche peut ĂȘtre entravĂ©e par l'absence de structure du complexe protĂ©ine-ligand. C'est pour rĂ©pondre Ă ce besoin que nous prĂ©sentons dans ce travail de thĂšse, une mĂ©thode capable de dĂ©terminer la structure de complexes protĂ©ine-ligands. Dans la mĂ©thode INPHARMA (Inter-ligands Nuclear Overhauser Effect for Pharmacophore Mapping), les inter-ligands NOEs (INPHARMA NOEs) sont utilisĂ©s pour dĂ©terminer l'orientation relative de deux ligands qui interagissent de maniĂšre compĂ©titive avec un mĂȘme rĂ©cepteur. Cette nouvelle approche ouvre la voie Ă des applications pharmaceutiques, Ă©galement au stade initial du dĂ©veloppement, quand l'information structurale via la cristallographie par Rayons X est difficile d'accĂšs
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