Charge coupled device (CCD) area detector for on-line (40- to 80-ms) acquisition of Laue diffraction data from protein crystals

When protein crystals are submicrometre-sized, X-ray radiation damage precludes conventional diffraction data collection. For crystals that are of the order of 100 nm in size, at best only single-shot diffraction patterns can be collected and rotation data collection has not been possible, irrespective of the diffraction technique used. Here, it is shown that at a very low electron dose (at most 0.1 e− Å−2), a Medipix2 quantum area detector is sufficiently sensitive to allow the collection of a 30-frame rotation series of 200 keV electron-diffraction data from a single ∼100 nm thick protein crystal. A highly parallel 200 keV electron beam (λ = 0.025 Å) allowed observation of the curvature of the Ewald sphere at low resolution, indicating a combined mosaic spread/beam divergence of at most 0.4°. This result shows that volumes of crystal with low mosaicity can be pinpointed in electron diffraction. It is also shown that strategies and data-analysis software (MOSFLMandSCALA) from X-ray protein crystallography can be used in principle for analysing electron-diffraction data from three-dimensional nanocrystals of proteins.

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A system for collection and on-line integration of X-ray diffraction data from a multiwire area detector

Journal of Applied Crystallography ◽

10.1107/s0021889887086783 ◽

1987 ◽

Vol 20 (3) ◽

pp. 235-242 ◽

Cited By ~ 109

Author(s):

M. Blum ◽

P. Metcalf ◽

S. C. Harrison ◽

D. C. Wiley

Keyword(s):

Diffraction Data ◽

High Speed ◽

X Ray Diffraction ◽

Quality Of Data ◽

X Ray ◽

Camera Control ◽

Area Detector ◽

C Programming ◽

On Line ◽

Integrated Intensities

A system for collecting and measuring X-ray diffraction data from protein crystals has been developed for a multiwire area detector. Computer programs run concurrently on two microcomputers, which collect and reduce detector data to integrated intensities. The self-contained system consists of an X-ray area detector, a rotation/oscillation camera, and two microcomputers connected by a high-speed Ethernet network. One microcomputer is dedicated to operation of the detector, control of the camera, and storage of the raw data. The second microcomputer automatically integrates the data as they are collected and allows the user to monitor the quality of data as they are processed. The integration programs are written in Fortran 77 and have been designed to be portable. Additional programs for crystal alignment, detector and camera control, and graphics are written in the C programming language. A description of the system, some characteristics of the detector, and the results of data collection are presented.

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On-orbit calibration of camera parameters based on line-matrix charge-coupled device imagery

Optics and Precision Engineering ◽

10.3788/ope.20192704.0984 ◽

2019 ◽

Vol 27 (4) ◽

pp. 984-989 ◽

Cited By ~ 1

Author(s):

王建荣 WANG Jian-rong ◽

王任享 WANG Ren-xiang ◽

胡莘 HU Xin

Keyword(s):

Charge Coupled Device ◽

On Line ◽

Camera Parameters

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Accurate and highly complete synchrotron protein crystal Laue diffraction data using the ESRF CCD and the Daresbury Laue software

Journal of Synchrotron Radiation ◽

10.1107/s0909049599006342 ◽

1999 ◽

Vol 6 (5) ◽

pp. 995-1006 ◽

Cited By ~ 8

Author(s):

Y. P. Nieh ◽

J. Raftery ◽

S. Weisgerber ◽

J. Habash ◽

F. Schotte ◽

...

Keyword(s):

Diffraction Data ◽

Protein Crystal ◽

Laue Diffraction

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Estimation of errors in diffraction data measured by CCD area detectors

Journal of Applied Crystallography ◽

10.1107/s0021889810033418 ◽

2010 ◽

Vol 43 (6) ◽

pp. 1356-1371 ◽

Cited By ~ 26

Author(s):

David Waterman ◽

Gwyndaf Evans

Keyword(s):

Error Estimates ◽

Diffraction Data ◽

Measurement Errors ◽

Diffraction Spot ◽

Two Dimensional ◽

Detector Module ◽

Area Detector ◽

Profile Fitting

Current methods for diffraction-spot integration from CCD area detectors typically underestimate the errors in the measured intensities. In an attempt to understand fully and identify correctly the sources of all contributions to these errors, a simulation of a CCD-based area-detector module has been produced to address the problem of correct handling of data from such detectors. Using this simulation, it has been shown how, and by how much, measurement errors are underestimated. A model of the detector statistics is presented and an adapted summation integration routine that takes this into account is shown to result in more realistic error estimates. In addition, the effect of correlations between pixels on two-dimensional profile fitting is demonstrated and the problems surrounding improvements to profile-fitting algorithms are discussed. In practice, this requires knowledge of the expected correlation between pixels in the image.

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Processing of Protein Crystals using by Deep-UV Pulsed Laser

Acta Crystallographica Section A Foundations and Advances ◽

10.1107/s205327331409665x ◽

2014 ◽

Vol 70 (a1) ◽

pp. C334-C334

Author(s):

Yoshiaki Kawano ◽

Takaaki Hikima ◽

Kunio Hirata ◽

Seiki Baba ◽

Hironori Murakami ◽

...

Keyword(s):

Diffraction Data ◽

Processing System ◽

Spherical Shape ◽

Systematic Errors ◽

Mirror System ◽

Protein Crystal ◽

Protein Crystals ◽

X Rays ◽

Uv Laser ◽

Pass Through

The absorption of X-rays which pass through the protein crystal is possibly the largest source of systematic errors in macromolecular crystallography. Therefore we are developing protein crystal processing system using Pulsed UV Laser Soft Ablation (PULSA) technique [1] to reduce the systematic error as well as background scattering from cryoprotectant agents. For high-quality diffraction data collection from organic material, crystals are usually processed to spherical shape in order to keep X-ray path length in crystal constant. This dramatically reduces systematic errors caused by `absorption of X-rays'. Although shaping crystal was thought to be effective for protein crystallography, there was no usual technique to achieve this because protein crystals are exceedingly fragile against mechanical stress. We are developing protein crystal processing system using PULSA technique. In this system, short pulsed UV-laser (maximum power: 1.0 μJ/pulse, wavelength: 193.4 nm, duration: less than 1.3 nsec) is raised by NSL-193L (Nikon Corporation) and focused on 4 μmφ (FWHM). The focused laser is controlled by galvanomic mirror system and irradiates a sample. Combining this mirror system with four-axis goniometer enables to process crystal to arbitrary shape that is easily defined on GUI. Several protein crystals have been successfully processed into spherical, column and square pole shape, etc. In the case of crystal processed into column shape (diameter is 50 μm), in addition to reducing absorption effects, signal-noise ratio of diffraction data can be increased by removing cryoprotectant agent surrounding the crystal. This work was supported by "Platform for Drug Discovery, Informatics, and Structural Life Science" from MEXT, Japan.

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Deformation Textures in FCC Metals Subjected to Frictional and to Abrasive Wear

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.105.195 ◽

2005 ◽

Vol 105 ◽

pp. 195-200

Author(s):

Robert A. Schwarzer

Keyword(s):

Cross Sections ◽

Test Machine ◽

Angle Of Incidence ◽

Fcc Metals ◽

Area Detector ◽

Pole Figures ◽

Deformation Textures ◽

On Line ◽

Diffraction Patterns ◽

Pin On Disk

The surface texture in fcc metals has been investigated after wear tests in a dry-running pin-on-disk test machine and after metallographic surface grinding. X-ray pole figures have been measured at a low angle of incidence of the primary beam, using an area detector for recording the diffraction patterns. SAD pole figures have been acquired on cross sections on-line in the TEM for examining the gradient of texture and microstructure beneath the surface. The XRD and SAD pole figures have been evaluated by ODF calculation. Wear and abrasion textures are distinctly different both for copper and bronze as well as for brass.

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Matrix-free integration of image-plate diffraction data

Journal of Applied Crystallography ◽

10.1107/s0021889804034089 ◽

2005 ◽

Vol 38 (2) ◽

pp. 280-290 ◽

Cited By ~ 4

Author(s):

Ralf Müller ◽

Georg Roth

Keyword(s):

Coordinate System ◽

Single Crystals ◽

Diffraction Data ◽

Diffuse Scattering ◽

Area Detector ◽

Image Plate ◽

Data Collections ◽

Ccd Detectors ◽

Matrix Free ◽

Complete Program

Matrix-free integration of area-detector diffraction data is developed to interpret data collections from single crystals, twinned or multi-phased crystals as well as quasicrystals. A pixel-background method based on the algorithm described by Bolotovsky, White, Darovsky & Coppens [J. Appl. Cryst.(1995),28, 86–95] is employed. The method is modified by using an azimuthal coordinate system and distinguishes reliably between significant scattering intensities and background intensities. Very broad intensity distributions frome.g.powder rings can be determined and reflections superimposed by diffuse scattering can be integrated reliably. A complete program suite to process area-detector data, both from image-plate and CCD detectors, is presented. The program uses both matrix-free as well as matrix-based integration. The program is tested on single-crystal and twinned-crystal diffraction data.

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