High-resolution x-ray diffraction microscopy of specifically labeled yeast cells

Proc Natl Acad Sci U S A. 2010 Apr 20;107(16):7235-9. doi: 10.1073/pnas.0910874107. Epub 2010 Apr 5.

Abstract

X-ray diffraction microscopy complements other x-ray microscopy methods by being free of lens-imposed radiation dose and resolution limits, and it allows for high-resolution imaging of biological specimens too thick to be viewed by electron microscopy. We report here the highest resolution (11-13 nm) x-ray diffraction micrograph of biological specimens, and a demonstration of molecular-specific gold labeling at different depths within cells via through-focus propagation of the reconstructed wavefield. The lectin concanavalin A conjugated to colloidal gold particles was used to label the alpha-mannan sugar in the cell wall of the yeast Saccharomyces cerevisiae. Cells were plunge-frozen in liquid ethane and freeze-dried, after which they were imaged whole using x-ray diffraction microscopy at 750 eV photon energy.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Colloids / chemistry
  • Gold / chemistry
  • Imaging, Three-Dimensional / methods
  • Light
  • Microscopy, Electron / methods
  • Microscopy, Electron, Scanning / methods
  • Mutation
  • Normal Distribution
  • Repressor Proteins / genetics
  • Saccharomyces cerevisiae / metabolism*
  • Saccharomyces cerevisiae Proteins / genetics
  • Scattering, Radiation
  • Software
  • X-Ray Diffraction / methods*

Substances

  • Colloids
  • Repressor Proteins
  • Saccharomyces cerevisiae Proteins
  • Whi5 protein, S cerevisiae
  • Gold