Protein Crystallography at Ultra-Short Wavelengths: Feasibility Study of Anomalous-Dispersion Experiments at the Xenon K-edge.
A protein crystallography experiment at the xenon K-edge (lambda = 0.358 A) has been successfully carried out at the materials science beamline (BL2/ID11) of the ESRF. The samples used in this methodological study were crystals of porcine pancreatic elastase, a 26 kDa protein of known structure. The diffraction data are of excellent quality. The combination of isomorphous replacement and anomalous dispersion of a single xenon heavy-atom derivative allowed accurate phase determination and the computation of a high-quality electron density map of the protein molecule. This is the first fully documented report on a complete protein crystallography experiment, from data collection up to phase determination and calculation of an electron density map, carried out with data obtained at ultra-short wavelengths. Experimental considerations as well as possible advantages and drawbacks of protein crystallography at very short and ultra-short wavelengths are discussed.
Schiltz
M
M
Kvick
A
A
Svensson
O S
OS
Shepard
W
W
de La Fortelle
E
E
Prangé
T
T
Kahn
R
R
Bricogne
G
G
Fourme
R
R