Dose, exposure time, and resolution in Serial X-ray Crystallography Metadata

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Title

  • Main Title Dose, exposure time, and resolution in Serial X-ray Crystallography

Creator

  • Author: Starodub, D
    Creator Type: Personal
  • Author: Rez, P
    Creator Type: Personal
  • Author: Hembree, G
    Creator Type: Personal
  • Author: Howells, M
    Creator Type: Personal
  • Author: Shapiro, D
    Creator Type: Personal
  • Author: Chapman, H N
    Creator Type: Personal
  • Author: Fromme, P
    Creator Type: Personal
  • Author: Schmidt, K
    Creator Type: Personal
  • Author: Weierstall, U
    Creator Type: Personal
  • Author: Doak, R B
    Creator Type: Personal
  • Author: Spence, J C
    Creator Type: Personal

Contributor

  • Sponsor: United States. Department of Energy.
    Contributor Type: Organization
    Contributor Info: USDOE

Publisher

  • Name: Lawrence Livermore National Laboratory
    Place of Publication: Livermore, California
    Additional Info: Lawrence Livermore National Laboratory (LLNL), Livermore, CA

Date

  • Creation: 2007-03-22

Language

  • English

Description

  • Content Description: Using detailed simulation and analytical models, the exposure time is estimated for serial crystallography, where hydrated laser-aligned proteins are sprayed across a continuous synchrotron beam. The resolution of X-ray diffraction microscopy is limited by the maximum dose that can be delivered prior to sample damage. In the proposed Serial Crystallography method, the damage problem is addressed by distributing the total dose over many identical hydrated macromolecules running continuously in a single-file train across a continuous X-ray beam, and resolution is then limited only by the available fluxes of molecules and X-rays. Orientation of the diffracting molecules is achieved by laser alignment. We evaluate the incident X-ray fluence (energy/area) required to obtain a given resolution from (1) an analytical model, giving the count rate at the maximum scattering angle for a model protein, (2) explicit simulation of diffraction patterns for a GroEL-GroES protein complex, and (3) the frequency cut off of the transfer function following iterative solution of the phase problem, and reconstruction of a density map in the projection approximation. These calculations include counting shot noise and multiple starts of the phasing algorithm. The results indicate the number of proteins needed within the beam at any instant for a given resolution and X-ray flux. We confirm an inverse fourth power dependence of exposure time on resolution, with important implications for all coherent X-ray imaging. We find that multiple single-file protein beams will be needed for sub-nanometer resolution on current third generation synchrotrons, but not on fourth generation designs, where reconstruction of secondary protein structure at a resolution of 7 {angstrom} should be possible with short (below 100 s) exposures.
  • Physical Description: PDF-file: 37 pages; size: 0.9 Mbytes

Subject

  • Keyword: Protein Structure
  • Keyword: Transfer Functions
  • Keyword: Orientation
  • Keyword: Coherent Scattering
  • Keyword: X-Ray Diffraction
  • Keyword: Diffraction
  • Keyword: Proteins
  • STI Subject Categories: 59 Basic Biological Sciences
  • Keyword: Scattering
  • Keyword: Microscopy
  • STI Subject Categories: 71 Classical And Quantumm Mechanics, General Physics
  • STI Subject Categories: 71 Classical And Quantumm Mechanics, General Physics
  • Keyword: Lasers
  • Keyword: Crystallography
  • Keyword: Simulation
  • Keyword: Resolution
  • Keyword: Alignment
  • Keyword: Synchrotrons

Source

  • Journal Name: Jounal of Synchrotron Research, vol. 15, no. 1, January 1, 2008, pp. 62-73; Journal Volume: 15; Journal Issue: 1

Collection

  • Name: Office of Scientific & Technical Information Technical Reports
    Code: OSTI

Institution

  • Name: UNT Libraries Government Documents Department
    Code: UNTGD

Resource Type

  • Article

Format

  • Text

Identifier

  • Report No.: UCRL-JRNL-229466
  • Grant Number: W-7405-ENG-48
  • Office of Scientific & Technical Information Report Number: 991522
  • Archival Resource Key: ark:/67531/metadc1013731