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Open Access
Abstract: Research towards using X-ray free-electron laser (XFEL) data to solve structures using experimental phasing methods such as sulfur single-wavelength anomalous dispersion (SAD) has been hampered by shortcomings in the diffraction models for X-ray diffraction from FELs. Owing to errors in the orientation matrix and overly simple partiality models, researchers have required large numbers of images to converge to reliable estimates for the structure-factor amplitudes, which may not be feasible for all biological systems. Here, data for cytoplasmic polyhedrosis virus type 17 (CPV17) collected at 1.3 Å wavelength at the Linac Coherent Light Source (LCLS) are revisited. A previously published definition of a partiality model for reflections illuminated by self-amplified spontaneous emission (SASE) pulses is built upon, which defines a fraction between 0 and 1 based on the intersection of a reflection with a spread of Ewald spheres modelled by a super-Gaussian wavelength distribution in the X-ray beam. A method of post-refinement to refine the parameters of this model is suggested. This has generated a merged data set with an overall discrepancy (by calculating the Rsplit value) of 3.15% to 1.46 Å resolution from a 7225-image data set. The atomic numbers of C, N and O atoms in the structure are distinguishable in the electron-density map. There are 13 S atoms within the 237 residues of CPV17, excluding the initial disordered methionine. These only possess 0.42 anomalous scattering electrons each at 1.3 Å wavelength, but the 12 that have single predominant positions are easily detectable in the anomalous difference Fourier map. It is hoped that these improvements will lead towards XFEL experimental phase determination and structure determination by sulfur SAD and will generally increase the utility of the method for difficult cases.
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Jun 2015
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Carolin
Seuring
,
Kartik
Ayyer
,
Eleftheria
Filippaki
,
Miriam
Barthelmess
,
Jean-nicolas
Longchamp
,
Philippe
Ringler
,
Tommaso
Pardini
,
David H.
Wojtas
,
Matthew A.
Coleman
,
Katerina
Dörner
,
Silje
Fuglerud
,
Greger
Hammarin
,
Birgit
Habenstein
,
Annette E.
Langkilde
,
Antoine
Loquet
,
Alke
Meents
,
Roland
Riek
,
Henning
Stahlberg
,
Sébastien
Boutet
,
Mark S.
Hunter
,
Jason
Koglin
,
Mengning
Liang
,
Helen M.
Ginn
,
Rick P.
Millane
,
Matthias
Frank
,
Anton
Barty
,
Henry N.
Chapman
Open Access
Abstract: Here we present a new approach to diffraction imaging of amyloid fibrils, combining a free-standing graphene support and single nanofocused X-ray pulses of femtosecond duration from an X-ray free-electron laser. Due to the very low background scattering from the graphene support and mutual alignment of filaments, diffraction from tobacco mosaic virus (TMV) filaments and amyloid protofibrils is obtained to 2.7 Å and 2.4 Å resolution in single diffraction patterns, respectively. Some TMV diffraction patterns exhibit asymmetry that indicates the presence of a limited number of axial rotations in the XFEL focus. Signal-to-noise levels from individual diffraction patterns are enhanced using computational alignment and merging, giving patterns that are superior to those obtainable from synchrotron radiation sources. We anticipate that our approach will be a starting point for further investigations into unsolved structures of filaments and other weakly scattering objects.
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May 2018
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Detectors
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Saeed
Oghbaey
,
Antoine
Sarracini
,
Helen M.
Ginn
,
Olivier
Pare-labrosse
,
Anling
Kuo
,
Alexander
Marx
,
Sascha W.
Epp
,
Darren A.
Sherrell
,
Bryan T.
Eger
,
Yinpeng
Zhong
,
Rolf
Loch
,
Valerio
Mariani
,
Roberto
Alonso-mori
,
Silke
Nelson
,
Henrik T.
Lemke
,
Robin L.
Owen
,
Arwen R.
Pearson
,
David I.
Stuart
,
Oliver P.
Ernst
,
Henrike
Mueller-werkmeister
,
R. J. Dwayne
Miller
Open Access
Abstract: The advent of ultrafast highly brilliant coherent X-ray free-electron laser sources has driven the development of novel structure-determination approaches for proteins, and promises visualization of protein dynamics on sub-picosecond timescales with full atomic resolution. Significant efforts are being applied to the development of sample-delivery systems that allow these unique sources to be most efficiently exploited for high-throughput serial femtosecond crystallography. Here, the next iteration of a fixed-target crystallography chip designed for rapid and reliable delivery of up to 11 259 protein crystals with high spatial precision is presented. An experimental scheme for predetermining the positions of crystals in the chip by means of in situ spectroscopy using a fiducial system for rapid, precise alignment and registration of the crystal positions is presented. This delivers unprecedented performance in serial crystallography experiments at room temperature under atmospheric pressure, giving a raw hit rate approaching 100% with an effective indexing rate of approximately 50%, increasing the efficiency of beam usage and allowing the method to be applied to systems where the number of crystals is limited.
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Aug 2016
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Philip
Roedig
,
Helen M.
Ginn
,
Tim
Pakendorf
,
Geoff
Sutton
,
Karl
Harlos
,
Thomas S.
Walter
,
Jan
Meyer
,
Pontus
Fischer
,
Ramona
Duman
,
Ismo
Vartiainen
,
Bernd
Reime
,
Martin
Warmer
,
Aaron S.
Brewster
,
Iris D.
Young
,
Tara
Michels-clark
,
Nicholas K.
Sauter
,
Abhay
Kotecha
,
James
Kelly
,
David J.
Rowlands
,
Marcin
Sikorsky
,
Silke
Nelson
,
Daniel S.
Damiani
,
Roberto
Alonso-mori
,
Jingshan
Ren
,
Elizabeth E.
Fry
,
Christian
David
,
David I. Stuart
Stuart
,
Armin
Wagner
,
Alke
Meents
Abstract: We report a method for serial X-ray crystallography at X-ray free-electron lasers (XFELs), which allows for full use of the current 120-Hz repetition rate of the Linear Coherent Light Source (LCLS). Using a micropatterned silicon chip in combination with the high-speed Roadrunner goniometer for sample delivery, we were able to determine the crystal structures of the picornavirus bovine enterovirus 2 (BEV2) and the cytoplasmic polyhedrosis virus type 18 polyhedrin, with total data collection times of less than 14 and 10 min, respectively. Our method requires only micrograms of sample and should therefore broaden the applicability of serial femtosecond crystallography to challenging projects for which only limited sample amounts are available. By synchronizing the sample exchange to the XFEL repetition rate, our method allows for most efficient use of the limited beam time available at XFELs and should enable a substantial increase in sample throughput at these facilities.
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Jun 2017
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Talos-Talos Arctica at Diamond
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Open Access
Abstract: We demonstrate that ion-beam milling of frozen, hydrated protein crystals to thin lamella preserves the crystal lattice to near-atomic resolution. This provides a vehicle for protein structure determination, bridging the crystal size gap between the nanometer scale of conventional electron diffraction and micron scale of synchrotron microfocus beamlines. The demonstration that atomic information can be retained suggests that milling could provide such detail on sections cut from vitrified cells.
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Aug 2018
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I03-Macromolecular Crystallography
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Max O.
Wiedorn
,
Dominik
Oberthuer
,
Richard
Bean
,
Robin
Schubert
,
Nadine
Werner
,
Brian
Abbey
,
Martin
Aepfelbacher
,
Luigi
Adriano
,
Aschkan
Allahgholi
,
Nasser
Al-qudami
,
Jakob
Andreasson
,
Steve
Aplin
,
Salah
Awel
,
Kartik
Ayyer
,
Saša
Bajt
,
Imrich
Barák
,
Sadia
Bari
,
Johan
Bielecki
,
Sabine
Botha
,
Djelloul
Boukhelef
,
Wolfgang
Brehm
,
Sandor
Brockhauser
,
Igor
Cheviakov
,
Matthew A.
Coleman
,
Francisco
Cruz-mazo
,
Cyril
Danilevski
,
Connie
Darmanin
,
R. Bruce
Doak
,
Martin
Domaracky
,
Katerina
Dörner
,
Yang
Du
,
Hans
Fangohr
,
Holger
Fleckenstein
,
Matthias
Frank
,
Petra
Fromme
,
Alfonso M.
Gañán-calvo
,
Yaroslav
Gevorkov
,
Klaus
Giewekemeyer
,
Helen Mary
Ginn
,
Heinz
Graafsma
,
Rita
Graceffa
,
Dominic
Greiffenberg
,
Lars
Gumprecht
,
Peter
Göttlicher
,
Janos
Hajdu
,
Steffen
Hauf
,
Michael
Heymann
,
Susannah
Holmes
,
Daniel A.
Horke
,
Mark S.
Hunter
,
Siegfried
Imlau
,
Alexander
Kaukher
,
Yoonhee
Kim
,
Alexander
Klyuev
,
Juraj
Knoška
,
Bostjan
Kobe
,
Manuela
Kuhn
,
Christopher
Kupitz
,
Jochen
Küpper
,
Janine Mia
Lahey-rudolph
,
Torsten
Laurus
,
Karoline
Le Cong
,
Romain
Letrun
,
P. Lourdu
Xavier
,
Luis
Maia
,
Filipe R. N. C.
Maia
,
Valerio
Mariani
,
Marc
Messerschmidt
,
Markus
Metz
,
Davide
Mezza
,
Thomas
Michelat
,
Grant
Mills
,
Diana C. F.
Monteiro
,
Andrew
Morgan
,
Kerstin
Mühlig
,
Anna
Munke
,
Astrid
Münnich
,
Julia
Nette
,
Keith A.
Nugent
,
Theresa
Nuguid
,
Allen M.
Orville
,
Suraj
Pandey
,
Gisel
Pena
,
Pablo
Villanueva-perez
,
Jennifer
Poehlsen
,
Gianpietro
Previtali
,
Lars
Redecke
,
Winnie Maria
Riekehr
,
Holger
Rohde
,
Adam
Round
,
Tatiana
Safenreiter
,
Iosifina
Sarrou
,
Tokushi
Sato
,
Marius
Schmidt
,
Bernd
Schmitt
,
Robert
Schönherr
,
Joachim
Schulz
,
Jonas A.
Sellberg
,
M. Marvin
Seibert
,
Carolin
Seuring
,
Megan L.
Shelby
,
Robert L.
Shoeman
,
Marcin
Sikorski
,
Alessandro
Silenzi
,
Claudiu A.
Stan
,
Xintian
Shi
,
Stephan
Stern
,
Jola
Sztuk-dambietz
,
Janusz
Szuba
,
Aleksandra
Tolstikova
,
Martin
Trebbin
,
Ulrich
Trunk
,
Patrik
Vagovic
,
Thomas
Ve
,
Britta
Weinhausen
,
Thomas A.
White
,
Krzysztof
Wrona
,
Chen
Xu
,
Oleksandr
Yefanov
,
Nadia
Zatsepin
,
Jiaguo
Zhang
,
Markus
Perbandt
,
Adrian P.
Mancuso
,
Christian
Betzel
,
Henry
Chapman
,
Anton
Barty
Open Access
Abstract: The new European X-ray Free-Electron Laser is the first X-ray free-electron laser capable of delivering X-ray pulses with a megahertz inter-pulse spacing, more than four orders of magnitude higher than previously possible. However, to date, it has been unclear whether it would indeed be possible to measure high-quality diffraction data at megahertz pulse repetition rates. Here, we show that high-quality structures can indeed be obtained using currently available operating conditions at the European XFEL. We present two complete data sets, one from the well-known model system lysozyme and the other from a so far unknown complex of a β-lactamase from K. pneumoniae involved in antibiotic resistance. This result opens up megahertz serial femtosecond crystallography (SFX) as a tool for reliable structure determination, substrate screening and the efficient measurement of the evolution and dynamics of molecular structures using megahertz repetition rate pulses available at this new class of X-ray laser source.
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Oct 2018
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I03-Macromolecular Crystallography
Krios I-Titan Krios I at Diamond
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Jiandong
Huo
,
Yuguang
Zhao
,
Jingshan
Ren
,
Daming
Zhou
,
Helen M. E.
Duyvesteyn
,
Helen M.
Ginn
,
Loic
Carrique
,
Tomas
Malinauskas
,
Reinis R.
Ruza
,
Pranav N. M.
Shah
,
Tiong Kit
Tan
,
Pramila
Rijal
,
Naomi
Coombes
,
Kevin R.
Bewley
,
Julia A.
Tree
,
Julika
Radecke
,
Neil
Paterson
,
Piyasa
Supasa
,
Juthathip
Mongkolsapaya
,
Gavin R.
Screaton
,
Miles
Carroll
,
Alain
Townsend
,
Elizabeth E.
Fry
,
Raymond J.
Owens
,
David I.
Stuart
Diamond Proposal Number(s):
[19946, 26983]
Open Access
Abstract: There are as yet no licenced therapeutics for the COVID-19 pandemic. The causal coronavirus (SARS-CoV-2) binds host cells via a trimeric Spike whose receptor binding domain (RBD) recognises angiotensin-converting enzyme 2 (ACE2), initiating conformational changes that drive membrane fusion. We find that the monoclonal antibody CR3022 binds the RBD tightly, neutralising SARS-CoV-2 and report the crystal structure at 2.4 Å of the Fab/RBD complex. Some crystals are suitable for screening for entry-blocking inhibitors. The highly conserved, structure-stabilising, CR3022 epitope is inaccessible in the prefusion Spike, suggesting that CR3022 binding facilitates conversion to the fusion-incompetent post-fusion state. Cryo-EM analysis confirms that incubation of Spike with CR3022 Fab leads to destruction of the prefusion trimer. Presentation of this cryptic epitope in an RBD-based vaccine might advantageously focus immune responses. Binders at this epitope may be useful therapeutically, possibly in synergy with an antibody blocking receptor attachment.
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Jun 2020
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Open Access
Abstract: As serial femtosecond crystallography expands towards a variety of delivery methods, including chip-based methods, and smaller collected data sets, the requirement to optimize the data analysis to produce maximum structure quality is becoming increasingly pressing. Here cppxfel, a software package primarily written in C++, which showcases several data analysis techniques, is released. This software package presently indexes images using DIALS (diffraction integration for advanced light sources) and performs an initial orientation matrix refinement, followed by post-refinement of individual images against a reference data set. Cppxfel is released with the hope that the unique and useful elements of this package can be repurposed for existing software packages. However, as released, it produces high-quality crystal structures and is therefore likely to be also useful to experienced users of X-ray free-electron laser (XFEL) software who wish to maximize the information extracted from a limited number of XFEL images.
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Jun 2016
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I24-Microfocus Macromolecular Crystallography
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Diamond Proposal Number(s):
[6387]
Open Access
Abstract: Polyhedra represent an ancient system used by a number of insect viruses to protect virions during long periods of environmental exposure. We present high resolution crystal structures of polyhedra for seven previously uncharacterised types of cypoviruses, four using ab initio selenomethionine phasing (two of these required over 100 selenomethionine crystals each). Approximately 80% of residues are structurally equivalent between all polyhedrins (pairwise rmsd ⩽1.5Å), whilst pairwise sequence identities, based on structural alignment, are as little as 12%. These illustrate the effect of 400 million years of evolution on a system where the crystal lattice is the functionally conserved feature in the face of massive sequence variability. The conservation of crystal contacts is maintained across most of the molecular surface, except for a dispensable virus recognition domain. By spreading the contacts over so much of the protein surface the lattice remains robust in the face of many individual changes. Overall these unusual structural constraints seem to have skewed the molecule’s evolution so that surface residues are almost as conserved as the internal residues.
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Aug 2015
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Open Access
Abstract: Drug and fragment screening at X-ray crystallography beamlines has been a huge success. However, it is inevitable that more high-profile biological drug targets will be identified for which high-quality, highly homogenous crystal systems cannot be found. With increasing heterogeneity in crystal systems, the application of current multi-data-set methods becomes ever less sensitive to bound ligands. In order to ease the bottleneck of finding a well behaved crystal system, pre-clustering of data sets can be carried out using cluster4x after data collection to separate data sets into smaller partitions in order to restore the sensitivity of multi-data-set methods. Here, the software cluster4x is introduced for this purpose and validated against published data sets using PanDDA, showing an improved total signal from existing ligands and identifying new hits in both highly heterogenous and less heterogenous multi-data sets. cluster4x provides the researcher with an interactive graphical user interface with which to explore multi-data set experiments.
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Nov 2020
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