The capillary top free crystal mounting method

Formerly, we named it as the "loopless" crystal mounting method. But now we leave the whole loop after flash freeze the crystal.
This "free" crystal mount technique has been developed for the sulfur SAD phasing method using longer wavelength X-ray from a chromium anode target (2.29 angstrom). With this technique, it is possible to solve novel protein structures using the anomalous signal from sulfur atoms in the underivatized native protein.

At synchrotron beamlines, this loopless free mounting method also aids analyses of micro crystals that are difficult to center in the lens-shaped frozen buffer in the cryoloop.

MPEG movies

Real time movie, 20% slow speed movie
Remove the loop (real time)
One division of the scale is 50 microns.
All movies were taken by Yu Kitago, Hokkaido Univ. Protein crystal used here for these movie was hen egg lysozyme.

One division of the scale is 50 microns.

List of structures solved by S-SAD using Cr X-ray and the mounting method

References

  1. Kitago, Y., Watanabe, N. and Tanaka, I.:
    Structure determination of a novel protein by sulphur SAD using chromium radiation in combination with a new crystal mounting method,
    Acta Cryst., D61, 1013-1021 (2005).
    http://www.iucr.org/cgi-bin/paper?dz5036

  2. Watanabe, N., Kitago, Y., Tanaka, I., Wang, J., Gu. Y., Zheng, C. and Fan H.:
    Comparison of phasing methods for sulfur-SAD using in-house chromium radiation: case studies for standard proteins and 69-kDa protein,
    Acta Cryst., D61, 1533-1540 (2005).
    http://www.iucr.org/cgi-bin/paper?dz5050

  3. Watanabe, N.:
    From phasing to structure refinement in-house: Cr/Cu dual wavelength system and an loopless free crystal mounting method,
    Acta Cryst., D62, 891-896 (2006).
    http://www.iucr.org/cgi-bin/paper?dz5067