1n4f: Difference between revisions
New page: left|200px<br /><applet load="1n4f" size="450" color="white" frame="true" align="right" spinBox="true" caption="1n4f, resolution 1.78Å" /> '''Para-Arsanilate Deri... |
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[[Image:1n4f.jpg|left|200px]]<br /><applet load="1n4f" size=" | [[Image:1n4f.jpg|left|200px]]<br /><applet load="1n4f" size="350" color="white" frame="true" align="right" spinBox="true" | ||
caption="1n4f, resolution 1.78Å" /> | caption="1n4f, resolution 1.78Å" /> | ||
'''Para-Arsanilate Derivative of Hen Egg-White Lysozyme'''<br /> | '''Para-Arsanilate Derivative of Hen Egg-White Lysozyme'''<br /> | ||
==Overview== | ==Overview== | ||
Single/multiple-wavelength anomalous dispersion (SAD/MAD) experiments were | 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. | ||
==About this Structure== | ==About this Structure== | ||
1N4F is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Gallus_gallus Gallus gallus] with NA, ASR and EDO as [http://en.wikipedia.org/wiki/ligands ligands]. Active as [http://en.wikipedia.org/wiki/Lysozyme Lysozyme], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=3.2.1.17 3.2.1.17] Full crystallographic information is available from [http:// | 1N4F is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Gallus_gallus Gallus gallus] with <scene name='pdbligand=NA:'>NA</scene>, <scene name='pdbligand=ASR:'>ASR</scene> and <scene name='pdbligand=EDO:'>EDO</scene> as [http://en.wikipedia.org/wiki/ligands ligands]. Active as [http://en.wikipedia.org/wiki/Lysozyme Lysozyme], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=3.2.1.17 3.2.1.17] Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1N4F OCA]. | ||
==Reference== | ==Reference== | ||
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[[Category: hydrolase]] | [[Category: hydrolase]] | ||
''Page seeded by [http:// | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 14:02:09 2008'' | ||
Revision as of 15:02, 21 February 2008
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Para-Arsanilate Derivative of Hen Egg-White Lysozyme
OverviewOverview
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.
About this StructureAbout this Structure
1N4F is a Single protein structure of sequence from Gallus gallus with , and as ligands. Active as Lysozyme, with EC number 3.2.1.17 Full crystallographic information is available from OCA.
ReferenceReference
Phasing power at the K absorption edge of organic arsenic., Retailleau P, Prange T, Acta Crystallogr D Biol Crystallogr. 2003 May;59(Pt 5):887-96. Epub 2003, Apr 25. PMID:12777806
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