1x2w
From Proteopedia
| Line 1: | Line 1: | ||
| - | [[Image:1x2w.gif|left|200px]] | + | [[Image:1x2w.gif|left|200px]] |
| - | + | ||
| - | '''Crystal Structure of Apo-Habu IX-bp at pH 4.6''' | + | {{Structure |
| + | |PDB= 1x2w |SIZE=350|CAPTION= <scene name='initialview01'>1x2w</scene>, resolution 2.29Å | ||
| + | |SITE= | ||
| + | |LIGAND= <scene name='pdbligand=CL:CHLORIDE+ION'>CL</scene>, <scene name='pdbligand=RB:RUBIDIUM+ION'>RB</scene> and <scene name='pdbligand=SO4:SULFATE ION'>SO4</scene> | ||
| + | |ACTIVITY= | ||
| + | |GENE= | ||
| + | }} | ||
| + | |||
| + | '''Crystal Structure of Apo-Habu IX-bp at pH 4.6''' | ||
| + | |||
==Overview== | ==Overview== | ||
| Line 7: | Line 16: | ||
==About this Structure== | ==About this Structure== | ||
| - | 1X2W is a [ | + | 1X2W is a [[Protein complex]] structure of sequences from [http://en.wikipedia.org/wiki/Trimeresurus_flavoviridis Trimeresurus flavoviridis]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1X2W OCA]. |
==Reference== | ==Reference== | ||
| - | pH-Dependent structural changes at Ca(2+)-binding sites of coagulation factor IX-binding protein., Suzuki N, Fujimoto Z, Morita T, Fukamizu A, Mizuno H, J Mol Biol. 2005 Oct 14;353(1):80-7. PMID:[http:// | + | pH-Dependent structural changes at Ca(2+)-binding sites of coagulation factor IX-binding protein., Suzuki N, Fujimoto Z, Morita T, Fukamizu A, Mizuno H, J Mol Biol. 2005 Oct 14;353(1):80-7. PMID:[http://www.ncbi.nlm.nih.gov/pubmed/16165155 16165155] |
[[Category: Protein complex]] | [[Category: Protein complex]] | ||
[[Category: Trimeresurus flavoviridis]] | [[Category: Trimeresurus flavoviridis]] | ||
| Line 25: | Line 34: | ||
[[Category: heterodimer]] | [[Category: heterodimer]] | ||
| - | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Mar 20 15:04:30 2008'' |
Revision as of 13:04, 20 March 2008
| |||||||
| , resolution 2.29Å | |||||||
|---|---|---|---|---|---|---|---|
| Ligands: | , and | ||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||
Crystal Structure of Apo-Habu IX-bp at pH 4.6
Overview
Coagulation factor IX-binding protein, isolated from Trimeresurus flavoviridis (IX-bp), is a C-type lectin-like protein. It is an anticoagulant consisting of homologous subunits, A and B. Each subunit has a Ca(2+)-binding site with a unique affinity (K(d) values of 14muM and 130muM at pH 7.5). These binding characteristics are pH-dependent and, under acidic conditions, the Ca(2+) binding of the low-affinity site was reduced considerably. In order to identify which site has high affinity and to investigate the pH-dependent Ca(2+) release mechanism, we have determined the crystal structures of IX-bp at pH 6.5 and pH 4.6 (apo form), and compared the Ca(2+)-binding sites with each other and with those of the solved structures under alkaline conditions; pH 7.8 and pH 8.0 (complexed form). At pH 6.5, Glu43 in the Ca(2+)-binding site of subunit A displayed two conformations. One (minor) is that in the alkaline state, and the other (major) is that at pH 4.6. However, the corresponding Gln43 residue of subunit B is in only a single conformation, which is almost identical with that in the alkaline state. At pH 4.6, Glu43 of subunit A adopts a conformation similar to that of the major conformer observed at pH 6.5, while Gln43 of subunit B assumes a new conformation, and both Ca(2+) positions are occupied by water molecules. These results showed that Glu43 of subunit A is much more sensitive to protonation than Gln43 of subunit B, and the conformational change of Glu43 occurs around pH6.5, which may correspond to the step of Ca(2+) release.
About this Structure
1X2W is a Protein complex structure of sequences from Trimeresurus flavoviridis. Full crystallographic information is available from OCA.
Reference
pH-Dependent structural changes at Ca(2+)-binding sites of coagulation factor IX-binding protein., Suzuki N, Fujimoto Z, Morita T, Fukamizu A, Mizuno H, J Mol Biol. 2005 Oct 14;353(1):80-7. PMID:16165155
Page seeded by OCA on Thu Mar 20 15:04:30 2008
