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Professor Poignard among the most cited researchers in the worldCongratulations to Professor Poignard who has been named a Thomson Reuters Highly Cited Researcher. Every year, the publishing company Thomson Reuters (now Clarivate Analytics) analyses scientific articles covering 21 disciplinary fields, published over the past 11 years in international journals. These data provide a list of about 3000 researchers (from more than 9 million researchers worldwide) who have distinguished themselves by publishing a large number of articles that rank among the 1% most cited in their respective fields. Pascal Poignard, head of the HIV and Persistent Human Viruses Group at IBS and Professor (CHUGA & UGA), is on the 2017 list of the 3,300 most cited researchers in the world (category ’Microbiology’). |
New light on bacteriophages, bacteria killers
Bacteriophage T5 tail tube structure suggests a trigger mechanism for Siphoviridae DNA ejection. Charles-Adrien Arnaud, Grégory Effantin, Corinne Vivès, Sylvain Engilberge, Maria Bacia, Pascale Boulanger, Eric Girard, Guy Schoehn and Cécile Breyton. Nature Communication doi:10.1038/s41467-017-02049-3 |
Innovative and specific painting of the pneumococcal surface
Specific and spatial labeling of choline-containing teichoic acids in Streptococcus pneumoniae by click chemistry. Di Guilmi AM, Bonnet J, Peiβert S, Durmort C, Gallet B, Vernet T, Gisch N, Wong YS. Chemical Commununications (Camb) ;53(76):10572-10575 |
Channelrhodopsin reveals its dark secretsIon channels are integral membrane proteins that upon stimulation modulate the flow of ions across the cell or organelle membrane. Channelrhodopsins (ChRs) appeared to be unusual channels. They belong to the large family of microbial rhodopsins, seven-helical transmembrane proteins containing retinal as chromophore. Photon absorption initiates retinal isomerization resulting in a photocycle, with different spectroscopically distinguishable intermediates, thereby controlling the opening and closing of the channel. In 2003, it was demonstrated that light-induced currents by heterologously expressed ChannelRhodopsin2 (ChR2) can be used to change a host`s membrane potential. This accomplishment has made ChR2 the first long thought and further used a key instrument of neuroscience. ChR2 opened a new field - optogenetics. Optogenetics is a biological technique which involves the use of light to control cells in living tissue, typically neurons, that have been genetically modified to express special light-sensitive proteins. In 2010, optogenetics was chosen as the "Method of the Year" across all fields of science and engineering by the interdisciplinary research journal Nature Methods. Despite the extraordinary importance of this protein, a high-resolution structure and structural mechanisms of a native ChR2 (and other ChRs) have not yet been known. A step forward was the structure of a chimera between ChannelRhodopsin1 and ChannelRhodopsin 2 (C1C2). However, recent electrophysiological and Fourier transform infrared data showed that C1C2 exhibits light-induced responses that are functionally and mechanistically different from ChR2. Given that ChR2 is the most frequently used tool in optogenetics, a high-resolution structure of ChR2 is of high importance. Deciphering the structure of the native channel would shed light on how the light-induced changes at the retinal Schiff base (RSB) are linked to the channel operation. In this work scientist from the MEMBRANE group and their collaborators expressed ChR2 in LEXSY expression system and used in meso crystallization approach to determine the crystal structure of the wild-type ChR2 and C128T slow mutant at 2.4 and 2.7 Å, respectively. The determined structures of ChR2 and its C128T mutant present the molecular basis for the understanding of ChR functioning. They provide insights into mechanisms of channel opening and closing. Thereby, this work shed light to the molecular mechanisms of Channelrhodopsin 2 work and opens the possibilities to make engineering of enhanced optogenetic tools more efficient. Structural insights into ion conduction by channelrhodopsin 2. Volkov O, Kovalev K., Polovinkin V, Borshchevskiy V, Bamann C, Astashkin R, Marin E, Popov A, Balandin T, Willbold D, Büldt G, Bamberg E, Gordeliy V. Science : Vol. 358, Issue 6366, pp. 1000-1001. |
Structure of the DNA polymerase of the vaccinia virus
The vaccinia virus DNA polymerase structure provides insights into the mode of processivity factor binding. Tarbouriech N, Ducournau C, Hutin S, Mas PJ, Man P, Forest E, Hart DJ, Peyrefitte CN, Burmeister WP, Iseni F. Nature Communications ;8(1):1455 |
Resistance to antibiotics : a new target in the bacterial wall
Molecular architecture of the PBP2:MreC core bacterial cell wall synthesis complex. Contreras-Martel C, Martins A, Ecobichon C, Maragno Trindade D, Mattei PJ, El Ghachi M, Hicham S, Hardouin P, Boneca IG, Dessen A. Nature Communications |
Inauguration of a Cryo-EM platform on EPN Campus
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Nobel Prize in Chemistry put structural biology on the forefrontThe jury of the 2017 Nobel Prize in Chemistry put structural biology on the forefront. Jacques Dubochet, Joachim Frank and Richard Henderson, an international trio of scientists, are honored for the development of cryo-electron microscopy, a tool for the determination of the 3D structure of biomolecules. "More precisely, this technique allows to freeze biological molecules in their native structure and to observe them under the electron microscope at atomic scale," explains Guy Schoehn, head of the Methods & Electron Microscopy Group at the IBS. Amorphous/vitrious ice and high-level detection It all began in 1988 with the will to develop electron microscopy, up to there devoted to material science, to decipher the structure of biological objects. "Indeed, the ultra vacuum present in the microscope column coupled with the irradiation of the sample by electrons destroys it very quickly !" pursues the scientist. « In cause : the water contained in these macromolecules, which evaporates under vacuum, and which coupled with the heating due to the interactions with electrons destroys the structure of the sample (the sample is literally bowling). Jacques Dubochet developed an ultra-fast freezing protocol that transforms liquid water into vitreous ice. Unlike ice crystals in our freezers, water in a vitreous ice is translucent to electrons. The first obstacle was crossed. However, the bet was not won because the samples, even at low temperature, move under the electron beam, and moreover, because the mechanical stability of an electron microscope is not perfect. Thus it was necessary to obtain more precise images (without drift or without fuzziness) to develop much faster but also more sensitive detectors with a very good signal to noise ratio, underlines Guy Schoehn. Richard Henderson took up this challenge by detecting each electron, with a rate of several hundred frames per second. Then the 3rd Nobel Prize-winning researcher, Joachim Frank, succeeded in moving from noisy cryo-electron microscopy images (recorded on photographic films at that time) to three dimensional structure of the object. The ribosome, a cellular factory translating RNA into proteins was one of the first macromolecular assemblies imaged and reconstructed by Joachim Frank. A 2nd state-of-the-art cryo-electron microscope soon to be inaugurated in France Electron microscopy is one of the main techniques used to decipher the structure of living organisms at the atomic scale, with crystallography and NMR (nuclear magnetic resonance). However, crystallography requires crystals and « freeze » the structure in a conformation compatible with crystallization (which is therefore not exactly in its physiological environment) and NMR is limited in size . "France did not bet on cryo-electron microscopy, unlike Germany or the United Kingdom and is far behind" the IBS researcher regrets. There is only one state-of-the-art instrument in France (a Krios electron microscope available for academic researchers in Strasbourg) by comparison with more than a dozen in UK or in Germany. Nevertheless, the most powerful electron microscope at the IBS in Grenoble (a Polara microscope installed in 2010) allows scientists to get results at atomic resolution but the risk for this microscope to become obsolete very quickly is high. Decrypt measles, adenoviruses, phages ... |
Crystallophore, an all-in-one tool for protein crystallography
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FRM team label for the Viral Replication Machines Group of Marc JaminThe Viral Replication Machines Group of the IBS has just been certified as FRM team. About 30 french teams are certified by the "Fondation pour la Recherche Médicale" (FRM) each year. What is this project about ? |
New light on fluorescent proteins dark states
Photoswitching of Green mEos2 by Intense 561-nm Light Perturbs Efficient Green-to-Red Photoconversion in Localization Microscopy. D. Thédié, R. Berardozzi, V. Adam, D. Bourgeois. J. Phys. Chem. Lett., 2017, 8, 4424−4430 A General Mechanism of Photoconversion of Green-to-Red Fluorescent Proteins Based on Blue and Infrared Light Reduces Phototoxicity in Live-Cell Single-Molecule Imaging. B. Turkowyd, A. Balinovic, D. Virant, H. G. Gölz Carnero, F. Caldana, M. Endesfelder, D. Bourgeois, and U. Endesfelder. Angewandte Chemie International Edition England ; 56, 1-7 |
AminoCraft :a gameplay to learn amino acidsTwo associate professors at Université Grenoble Alpes (UGA) have developed an app that teaches the structure of the 20 amino acids which are the building blocks of all living creatures. The application is available for free on Android and Apple smartphones, in English and French and it does not require a network connection to play. It provides a great way for students, and those who are curious, to have fun while quickly learning the amino acids on their smart phone, any time of the day, while commuting, in the street or on a coffee break. The development of this application was made possible thanks to funding from the Region Rhône Alpes Auvergne and assistance from Unvisersité Grenoble Aples (UGA). |
Ultra-fast molecular movie : watching proteins absorbing light
Chromophore twisting in the excited state of a fluorescent protein captured by time-resolved serial femtosecond crystallography. Coquelle N, Sliwa M, Woodhouse J, Schirò G, Adam V, Aquila A, Barends T, Boutet S, Byrdin M, Carbajo S, De la Mora E, Doak B, Feliks M, Fieschi F, Foucar L, Guillon V, Hilpert M, Hunter M, Jakobs S, Koglin J, Kovacsova G, Lane TJ, Lévy B, Liang M, Nass K, Ridard J, Robinson J, Roome C, Ruckebusch C, Seaberg M, Thepaut M, Cammarata M, Demachy I, Field M, Shoeman R, Bourgeois D, Colletier J-P, Schlichting I, Weik M. Nature Chemistry |
NMR a tool to detect ultraweak interactions in proteins
Observation of CH⋅⋅⋅π Interactions between Methyl and Carbonyl Groups in Proteins. Perras FA, Marion D, Boisbouvier J, Bryce DL, Plevin MJ. Angewandte Chemie-International Edition England doi : 10.1002/anie.201702626 |
Protein dynamics in the crystal : a subtle balance of inter- and intramolecular contacts
Slow conformational exchange and overall rocking motion in ubiquitin protein crystals. Kurauskas V, Izmailov SA, Rogacheva O, Hessel A, Ayala I, Woodhouse J, Shilova A, Xue Y, Yuwen T, Coquelle N, Colletier JP, Skrynnikov NR, Schanda P. Nature Communications DOI:10.1038/10.1038/s41467-017-00165-8 |
Mechanism of transmembrane signaling by sensor histidine kinases
Mechanism of transmembrane signaling by sensor histidine kinases. Gushchin I, Melnikov I, Polovinkin V, Ishchenko A, Yuzhakova A, Buslaev P, Bourenkov G, Grudinin S, Round E, Balandin T, Borshchevskiy V, Willbold D, Leonard G, Büldt G, Popov A, Gordeliy V. Science ;356(6342 |
How plankton dominate ocean life
Plastid thylakoid architecture optimises photosynthesis in diatoms. Flori S, Jouneau PH, Bailleul B, Gallet B, Estrozi LF, Moriscot C, Bastien O, Eicke S, Schober A, Río Bártulos C, Maréchal E, Kroth PG, Petroutsos D, Zeeman S, Breyton C, Schoehn G, Falconet D and Finazzi G. Nature Communications ;8:15885. |
Human Immune Protein C1q Selectively Disaggregates Carbon Nanotubes
Human Immune Protein C1q Selectively Disaggregates Carbon Nanotubes. Saint-Cricq M, Carrete J, Gaboriaud C, Gravel E, Doris E, Thielens N, Mingo N, Ling WL. Nano Letters ;17(6):3409-3415 |
A new antifungal therapeutic strategy
* Team Petosa (Institut de Biologie Structurale), Jérôme Govin (Institut de Biosciences et Biotechnologies de Grenoble), Muriel Cornet (TIMC-IMAG-TheREx, CHU Grenoble Alpes), Christophe d’Enfert (Institut Pasteur) and Charles McKenna (University of Southern California, Los Angeles). Selective BET bromodomain inhibition as an antifungal therapeutic strategy. Mietton F, Ferri E, Champleboux M, Zala N, Maubon D, Zhou Y, Harbut M, Spittler D, Garnaud C, Courçon M, Chauvel M, d’Enfert C, Kashemirov BA, Hull M, Cornet M, McKenna CE, Govin J, Petosa C. Nature Communications 8:15482. |
Insights into a mechanism which inhibits root cell elongation
Low phosphate activates STOP1-ALMT1 to rapidly inhibit root cell elongation. Balzergue C, Dartevelle T, Godon C, Laugier E, Meisrimler C, Teulon J-M, Creff A, Bissler M, Brouchoud C, Hagège A, Müller J, Chiarenza S, Javot H, Becuwe-Linka N, David P, Péret B, Delannoy E, Thibaud M-C, Armangaud J, Abel S, Pellequer J-L, Nussaume L and Desnos T. Nat. Commun. 8 : 15300. |
Discovery of the structure of a fundamental particle of chromatin
Structure and Dynamics of a 197 bp Nucleosome in Complex with Linker Histone H1. Jan Bednar, Isabel Garcia-Saez, Ramachandran Boopathi, Amber R. Cutter, Gabor Papai, Anna Reymer, Sajad H. Syed, Imtiaz Nisar Lone, Ognyan Tonchev, Corinne Crucifix, Hervé Menoni, Christophe Papin, Dimitrios A. Skoufias, Hitoshi Kurumizaka, Richard Lavery, Ali Hamiche, Jeffrey J. Hayes, Patrick Schultz, Dimitar Angelov, Carlo Petosa, Stefan Dimitrov. Molecular Cell. Published : May 4, 2017. vol 66. issue 3, p384–397. |
Polyvalan (IBS & ENS Lyon Spin-off company) and Pulsalys sign an exclusive exploitation contract to easily determine the 3D structure of proteinsPULSALYS, the Lyon-Saint-Etienne Technology Transfer Acceleration Company, announces the signature of an exclusive license with POLYVALAN to facilitate the determination of protein structures. POLYVALAN, which benefits from the know-how of IBS and ENS-Lyon, specializes in the development, manufacture and marketing of innovative chemical additives dedicated to structural biology. Press release (in french only). |
Scientists uncover mechanism allowing bacteria to survive the human immune system
Crystal structures of the NO sensor NsrR reveal how its iron-sulfur cluster modulates DNA binding. Anne Volbeda, Erin L. Dodd, Claudine Darnault, Jason C. Crack, Oriane Renoux, Matthew I. Hutchings, Nick E. Le Brun & Juan C. Fontecilla-Camps. Nature Com ;8:15052 |
Development of innovative strategies to monitor formation of biological structures
Unraveling Self-Assembly Pathways of the 468 kDa Proteolytic Machine TET2. Pavel Macek, Rime Kerfah, Elisabetta Boeri Erba, Elodie Crublet, Christine Moriscot, Guy Schoehn, Carlos Amero, Jerome Boisbouvier. Science Advances ; vol3, n4, e1601601 |
The remarkable complexity of vitamin B6 biosynthesis
Lysine relay mechanism coordinates intermediate transfer in vitamin B6 biosynthesis. Rodrigues M, Windeisen V, Zhang Y, Guedez G, Weber S, Strohmeier M, Hanes J, Royant A, Evans G, Sinning I, Ealick S, Begley T & Tews I. Nat. Chem. Biol. ;13(3):290-294. |
Insights into the first step of nucleosome formation
Insights into the molecular architecture and histone H3-H4 deposition mechanism of yeast Chromatin assembly factor 1. Sauer PV, Timm J, Liu D, Sitbon D, Boeri-Erba E, Velours C, Mücke N, Langowski J, Ochsenbein F, Almouzni G, Panne D. Elife ;6. pii : e23474. doi : 10.7554/eLife.23474 |
Official opening of the CIBB 3D graphics roomThe Official opening of a 3D graphics room took place on Friday 17 February in the Carl-Ivar Brandèn Building (CIBB). This graphic room dedicated to master and doctoral courses in structural biology and on-site workshops offers 10 workstations operating under Debian linux with Nvidia 3D graphic displays and has the capacity to accommodate 20 students. Located on the CIBB ground floor on EPN campus, this room has been provided by the IBS, the material has been financed by the Labex “Grenoble Alliance for Integrated Structural & Cell Biology” (GRAL) and the UFR Biology-Chemistry of University Grenoble Alpes and the installation was done by some members of the Partnership in Structural Biology (PSB).
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Proton-detected solid-state NMR spectroscopy of a zinc diffusion facilitator in native nanodiscs
Proton-Detected Solid-State NMR Spectroscopy of a Zinc Diffusion Facilitator Protein in Native Nanodiscs. Bersch B, Dörr JM, Hessel A, Killian JA, Schanda P. Angew Chem Int Ed Engl. 2017 Jan 27. doi : 10.1002/anie.201610441. |
A new NMR tool for probing functional protein dynamics
Probing Conformational Exchange Dynamics in a Short-Lived Protein Folding Intermediate by Real-Time Relaxation–Dispersion NMR. FrancoSergio R, Caballero G, Ayala I, Favier A and Brutscher B. Journal of the American Chemical Society ; 139(3):1065-1068 |