1N4F: Para-Arsanilate Derivative Of Hen Egg-White Lysozyme

Acta Crystallogr. D Biol. Crystallogr. (2003) 59 p.887-896
Single/multiple-wavelength anomalous dispersion (SAD/MAD) experiments were performed on a crystal of an organic arsenic derivative of hen egg-white lysozyme. A para-arsanilate compound used as a crystallizing reagent was incorporated into the ordered solvent region of the lysozyme molecule. Diffraction data were collected to high resolution (</=2.0 A) at three wavelengths around the K edge (1.04 A) of arsenic at beamline BM30A, ESRF synchrotron. Anomalous Patterson maps clearly showed the main arsanilate site to be between three symmetry-related lysozyme molecules, at a location previously occupied by a para-toluenesulfonate anion. MAD phases at 2 A derived using the program SHARP led to an electron-density map of sufficient quality to start manual building of the protein model. Amplitudes from a second crystal measured to a resolution of 1.8 A at the peak wavelength revealed two additional heavy-atom sites, which reinforced the anomalous subset model and therefore dramatically improved the phasing power of the arsenic derivative. The subsequent solvent-flattened map was of such high accuracy that the program ARP/wARP was able to build a nearly complete model automatically. This work emphasizes the great potential of arsenic for de novo structure determination using anomalous dispersion methods.
PDB ID: 1N4FDownload
MMDB ID: 22663
PDB Deposition Date: 2002/10/31
Updated in MMDB: 2007/11
Experimental Method:
x-ray diffraction
Resolution: 1.78  Å
Source Organism:
Similar Structures:
Biological Unit for 1N4F: monomeric; determined by author
Molecular Components in 1N4F
Label Count Molecule
Protein (1 molecule)
Lysozyme C(Gene symbol: LYZ)
Molecule annotation
Chemicals (9 molecules)
* Click molecule labels to explore molecular sequence information.

Citing MMDB