scholarly journals A Perspective on Molecular Structure and Bond-Breaking in Radiation Damage in Serial Femtosecond Crystallography

Crystals ◽  
2020 ◽  
Vol 10 (7) ◽  
pp. 585 ◽  
Author(s):  
Carl Caleman ◽  
Francisco Jares Junior ◽  
Oscar Grånäs ◽  
Andrew V. Martin
Keyword(s):  
Radiation Damage ◽  
Protein Dynamics ◽  
Conformational Changes ◽  
Bond Breaking ◽  
Time Resolved ◽  
Metal Centers ◽  
Disulfide Bonding ◽  
X Ray ◽  
Sample Structure ◽  
Effects Of Radiation

X-ray free-electron lasers (XFELs) have a unique capability for time-resolved studies of protein dynamics and conformational changes on femto- and pico-second time scales. The extreme intensity of X-ray pulses can potentially cause significant modifications to the sample structure during exposure. Successful time-resolved XFEL crystallography depends on the unambiguous interpretation of the protein dynamics of interest from the effects of radiation damage. Proteins containing relatively heavy elements, such as sulfur or metals, have a higher risk for radiation damage. In metaloenzymes, for example, the dynamics of interest usually occur at the metal centers, which are also hotspots for damage due to the higher atomic number of the elements they contain. An ongoing challenge with such local damage is to understand the residual bonding in these locally ionized systems and bond-breaking dynamics. Here, we present a perspective on radiation damage in XFEL experiments with a particular focus on the impacts for time-resolved protein crystallography. We discuss recent experimental and modelling results of bond-breaking and ion motion at disulfide bonding sites in protein crystals.

scholarly journals Temperature-Jump Solution X-ray Scattering Reveals Distinct Motions in a Dynamic Enzyme

2018 ◽  
Author(s):  
Michael C. Thompson ◽  
Benjamin A. Barad ◽  
Alexander M. Wolff ◽  
Hyun Sun Cho ◽  
Friedrich Schotte ◽  
...  
Keyword(s):  
Protein Dynamics ◽  
Conformational Changes ◽  
Thermal Excitation ◽  
Relaxation Processes ◽  
Spectroscopic Techniques ◽  
Time Resolved ◽  
X Ray ◽  
X Ray Scattering ◽  
Solvent Molecules ◽  
Ray Scattering

AbstractCorrelated motions of proteins and their bound solvent molecules are critical to function, but these features are difficult to resolve using traditional structure determination techniques. Time-resolved methods hold promise for addressing this challenge but have relied on the exploitation of exotic protein photoactivity, and are therefore not generalizable. Temperature-jumps (T-jumps), through thermal excitation of the solvent, have been implemented to study protein dynamics using spectroscopic techniques, but their implementation in X-ray scattering experiments has been limited. Here, we perform T-jump small- and wide-angle X-ray scattering (SAXS/WAXS) measurements on a dynamic enzyme, cyclophilin A (CypA), demonstrating that these experiments are able to capture functional intramolecular protein dynamics. We show that CypA displays rich dynamics following a T-jump, and use the resulting time-resolved signal to assess the kinetics of conformational changes in the enzyme. Two relaxation processes are resolved, which can be characterized by Arrhenius behavior. We also used mutations that have distinct functional effects to disentangle the relationship of the observed relaxation processes. A fast process is related to surface loop motions important for substrate specificity, whereas a slower process is related to motions in the core of the protein that are critical for catalytic turnover. These results demonstrate the power of time-resolved X-ray scattering experiments for characterizing protein and solvent dynamics on the μs-ms timescale. We expect the T-jump methodology presented here will be useful for understanding kinetic correlations between local conformational changes of proteins and their bound solvent molecules, which are poorly explained by the results of traditional, static measurements of molecular structure.

The kinetics of conformational changes of α2 -macroglobulin determined by time resolved X-ray solution scattering

FEBS Letters ◽  
1994 ◽  
Vol 337 (2) ◽  
pp. 171-174 ◽  
Author(s):  
Hideo Arakawa ◽  
Takuji Urisaka ◽  
Hirotsugu Tsuruta ◽  
Yoshiyuki Amemiya ◽  
Hiroshi Kihara ◽  
...  
Keyword(s):  
Conformational Changes ◽  
Time Resolved ◽  
X Ray ◽  
Α2 Macroglobulin ◽  
Kinetics Of

scholarly journals Predicting data quality in biological X-ray solution scattering

2018 ◽  
Vol 74 (8) ◽  
pp. 727-738
Author(s):  
Chenzheng Wang ◽  
Yuexia Lin ◽  
Devin Bougie ◽  
Richard E. Gillilan
Keyword(s):  
Conformational Changes ◽  
Sample Path ◽  
Flow Time ◽  
Photon Flux ◽  
Detector Efficiency ◽  
Time Resolved ◽  
Short Sample ◽  
X Ray ◽  
Path Lengths ◽  
Flux Energy

Biological small-angle X-ray solution scattering (BioSAXS) is now widely used to gain information on biomolecules in the solution state. Often, however, it is not obvious in advance whether a particular sample will scatter strongly enough to give useful data to draw conclusions under practically achievable solution conditions. Conformational changes that appear to be large may not always produce scattering curves that are distinguishable from each other at realistic concentrations and exposure times. Emerging technologies such as time-resolved SAXS (TR-SAXS) pose additional challenges owing to small beams and short sample path lengths. Beamline optics vary in brilliance and degree of background scatter, and major upgrades and improvements to sources promise to expand the reach of these methods. Computations are developed to estimate BioSAXS sample intensity at a more detailed level than previous approaches, taking into account flux, energy, sample thickness, window material, instrumental background, detector efficiency, solution conditions and other parameters. The results are validated with calibrated experiments using standard proteins on four different beamlines with various fluxes, energies and configurations. The ability of BioSAXS to statistically distinguish a variety of conformational movements under continuous-flow time-resolved conditions is then computed on a set of matched structure pairs drawn from the Database of Macromolecular Motions (http://molmovdb.org). The feasibility of experiments is ranked according to sample consumption, a quantity that varies by over two orders of magnitude for the set of structures. In addition to photon flux, the calculations suggest that window scattering and choice of wavelength are also important factors given the short sample path lengths common in such setups.

Limiting radiation damage for high-brilliance biological solution scattering: practical experience at the EMBL P12 beamline PETRAIII

2015 ◽  
Vol 22 (2) ◽  
pp. 273-279 ◽  
Author(s):  
Cy M. Jeffries ◽  
Melissa A. Graewert ◽  
Dmitri I. Svergun ◽  
Clément E. Blanchet
Keyword(s):  
Radiation Damage ◽  
Practical Experience ◽  
Quality Data ◽  
Biological Macromolecules ◽  
Sample Handling ◽  
X Ray ◽  
X Ray Scattering ◽  
Sample Position ◽  
Effects Of Radiation

Radiation damage is the general curse of structural biologists who use synchrotron small-angle X-ray scattering (SAXS) to investigate biological macromolecules in solution. The EMBL-P12 biological SAXS beamline located at the PETRAIII storage ring (DESY, Hamburg, Germany) caters to an extensive user community who integrate SAXS into their diverse structural biology programs. The high brilliance of the beamline [5.1 × 1012 photons s−1, 10 keV, 500 (H) µm × 250 (V) µm beam size at the sample position], combined with automated sample handling and data acquisition protocols, enable the high-throughput structural characterization of macromolecules in solution. However, considering the often-significant resources users invest to prepare samples, it is crucial that simple and effective protocols are in place to limit the effects of radiation damage once it has been detected. Here various practical approaches are evaluated that users can implement to limit radiation damage at the P12 beamline to maximize the chances of collecting quality data from radiation sensitive samples.

scholarly journals Approach of Serial Crystallography

Crystals ◽  
2020 ◽  
Vol 10 (10) ◽  
pp. 854
Author(s):  
Ki Hyun Nam
Keyword(s):  
Radiation Damage ◽  
Room Temperature ◽  
Time Resolved ◽  
X Ray ◽  
X Ray Crystallography ◽  
The Past ◽  
Wide Range ◽  
Experimental Limitation ◽  
Serial Crystallography ◽  
Collection Strategies

Radiation damage and cryogenic sample environment are an experimental limitation observed in the traditional X-ray crystallography technique. However, the serial crystallography (SX) technique not only helps to determine structures at room temperature with minimal radiation damage, but it is also a useful tool for profound understanding of macromolecules. Moreover, it is a new tool for time-resolved studies. Over the past 10 years, various sample delivery techniques and data collection strategies have been developed in the SX field. It also has a wide range of applications in instruments ranging from the X-ray free electron laser (XFEL) facility to synchrotrons. The importance of the various approaches in terms of the experimental techniques and a brief review of the research carried out in the field of SX has been highlighted in this editorial.

RADDOSE-3D: time- and space-resolved modelling of dose in macromolecular crystallography

2013 ◽  
Vol 46 (4) ◽  
pp. 1225-1230 ◽  
Author(s):  
Oliver B. Zeldin ◽  
Markus Gerstel ◽  
Elspeth F. Garman
Keyword(s):  
Data Collection ◽  
Radiation Damage ◽  
Diffraction Experiment ◽  
Macromolecular Crystallography ◽  
X Ray Diffraction ◽  
Time Resolved ◽  
X Ray ◽  
Online Methods ◽  
Crystal Volume ◽  
Number Of Iterations

RADDOSE-3D allows the macroscopic modelling of an X-ray diffraction experiment for the purpose of better predicting radiation-damage progression. The distribution of dose within the crystal volume is calculated for a number of iterations in small angular steps across one or more data collection wedges, providing a time-resolved picture of the dose state of the crystal. The code is highly modular so that future contributions from the community can be easily integrated into it, in particular to incorporate online methods for determining the shape of macromolecular crystals and better protocols for imaging real experimental X-ray beam profiles.

scholarly journals Ultrafast x-ray-driven phenomena in nanocrystals: development and application of powerful simulation tools

2019 ◽  
Vol 205 ◽  
pp. 05022
Author(s):  
Malik Muhammad Abdullah ◽  
Zoltan Jurek ◽  
Sang-Kil Son ◽  
Robin Santra
Keyword(s):  
Radiation Damage ◽  
Time Resolved ◽  
X Ray ◽  
Biologically Relevant ◽  
Simulation Tools ◽  
Damage Dynamics ◽  
Biologically Relevant Molecules ◽  
Dynamics Simulations

We investigate the radiation damage dynamics of nanocrystals at high x-ray intensity, by using time-resolved scattering patterns. We present dynamics simulations for biologically relevant molecules using XMDYN extended to nanocrystals and scattering simulation with XSINC.

scholarly journals Nanosecond pump–probe device for time-resolved serial femtosecond crystallography developed at SACLA

2017 ◽  
Vol 24 (5) ◽  
pp. 1086-1091 ◽  
Author(s):  
Minoru Kubo ◽  
Eriko Nango ◽  
Kensuke Tono ◽  
Tetsunari Kimura ◽  
Shigeki Owada ◽  
...  
Keyword(s):  
Conformational Changes ◽  
Free Electron ◽  
Good Choice ◽  
Cubic Phase ◽  
Liquid Droplets ◽  
Optical Pump ◽  
Time Resolved ◽  
X Ray ◽  
X Ray Crystallography ◽  
Serial Femtosecond Crystallography

X-ray free-electron lasers (XFELs) have opened new opportunities for time-resolved X-ray crystallography. Here a nanosecond optical-pump XFEL-probe device developed for time-resolved serial femtosecond crystallography (TR-SFX) studies of photo-induced reactions in proteins at the SPring-8 Angstrom Compact free-electron LAser (SACLA) is reported. The optical-fiber-based system is a good choice for a quick setup in a limited beam time and allows pump illumination from two directions to achieve high excitation efficiency of protein microcrystals. Two types of injectors are used: one for extruding highly viscous samples such as lipidic cubic phase (LCP) and the other for pulsed liquid droplets. Under standard sample flow conditions from the viscous-sample injector, delay times from nanoseconds to tens of milliseconds are accessible, typical time scales required to study large protein conformational changes. A first demonstration of a TR-SFX experiment on bacteriorhodopsin in bicelle using a setup with a droplet-type injector is also presented.

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