1gwg
From Proteopedia
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| , resolution 2.01Å | |||||||
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| Sites: | |||||||
| Ligands: | , | ||||||
| Resources: | FirstGlance, OCA, PDBsum, RCSB | ||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||
TRI-IODIDE DERIVATIVE OF APOFERRITIN
Overview
A series of experiments performed at Cu Kalpha wavelength on in-house X-ray equipment are presented which investigate two possibilities for enhancing the experimental phasing signal by means of (i) triiodide/iodide soaks using KI/I(2) and (ii) combinations of counter-ions introduced using the short cryosoak method. Triiodide-derivative crystal structures for five test proteins have been refined and reveal that iodine can bind as polyiodide and single iodide ions through hydrophobic and hydrogen-bonding interactions both at the molecular surface and in intramolecular and intermolecular cavities. In three cases, the structures could be automatically determined with autoSHARP using in-house SAD and SIRAS data. The investigation of combinatorial counter-ion replacement using multiple salts with Na(+) and Cs(+) as cations and I(-) and Cl(-) as anions reveals that, for the case of hen egg-white lysozyme, significant improvement in phasing signal is obtained by the combined use of salts compared with SIRAS methods using native and single short-soak derivative data sets.
About this Structure
1GWG is a Single protein structure of sequence from Equus caballus. Full crystallographic information is available from OCA.
Reference
Triiodide derivatization and combinatorial counter-ion replacement: two methods for enhancing phasing signal using laboratory Cu Kalpha X-ray equipment., Evans G, Bricogne G, Acta Crystallogr D Biol Crystallogr. 2002 Jun;58(Pt 6 Pt 2):976-91. Epub, 2002 May 29. PMID:12037300
Page seeded by OCA on Sun Mar 30 20:52:43 2008
