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1fif
From Proteopedia
| Line 4: | Line 4: | ||
|PDB= 1fif |SIZE=350|CAPTION= <scene name='initialview01'>1fif</scene>, resolution 1.95Å | |PDB= 1fif |SIZE=350|CAPTION= <scene name='initialview01'>1fif</scene>, resolution 1.95Å | ||
|SITE= | |SITE= | ||
| - | |LIGAND= <scene name='pdbligand=CA:CALCIUM+ION'>CA</scene> | + | |LIGAND= <scene name='pdbligand=CA:CALCIUM+ION'>CA</scene>, <scene name='pdbligand=CL:CHLORIDE+ION'>CL</scene> |
|ACTIVITY= | |ACTIVITY= | ||
|GENE= | |GENE= | ||
| + | |DOMAIN= | ||
| + | |RELATEDENTRY=[[1fih|1FIH]] | ||
| + | |RESOURCES=<span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1fif FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1fif OCA], [http://www.ebi.ac.uk/pdbsum/1fif PDBsum], [http://www.rcsb.org/pdb/explore.do?structureId=1fif RCSB]</span> | ||
}} | }} | ||
| Line 26: | Line 29: | ||
[[Category: Torgersen, D.]] | [[Category: Torgersen, D.]] | ||
[[Category: Weis, W I.]] | [[Category: Weis, W I.]] | ||
| - | [[Category: CA]] | ||
| - | [[Category: CL]] | ||
[[Category: c-type lectin]] | [[Category: c-type lectin]] | ||
[[Category: calcium-binding protein]] | [[Category: calcium-binding protein]] | ||
[[Category: lectin]] | [[Category: lectin]] | ||
| - | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Sun Mar 30 20:23:31 2008'' |
Revision as of 17:23, 30 March 2008
| |||||||
| , resolution 1.95Å | |||||||
|---|---|---|---|---|---|---|---|
| Ligands: | , | ||||||
| Related: | 1FIH
| ||||||
| Resources: | FirstGlance, OCA, PDBsum, RCSB | ||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||
N-ACETYLGALACTOSAMINE-SELECTIVE MUTANT OF MANNOSE-BINDING PROTEIN-A (QPDWG-HDRPY)
Overview
Efficient release of ligands from the Ca(2+)-dependent carbohydrate-recognition domain (CRD) of the hepatic asialoglycoprotein receptor at endosomal pH requires a small set of conserved amino acids that includes a critical histidine residue. When these residues are incorporated at corresponding positions in an homologous galactose-binding derivative of serum mannose-binding protein, the pH dependence of ligand binding becomes more like that of the receptor. The modified CRD displays 40-fold preferential binding to N-acetylgalactosamine compared with galactose, making it a good functional mimic of the asialoglycoprotein receptor. In the crystal structure of the modified CRD bound to N-acetylgalactosamine, the histidine (His(202)) contacts the 2-acetamido methyl group and also participates in a network of interactions involving Asp(212), Arg(216), and Tyr(218) that positions a water molecule in a hydrogen bond with the sugar amide group. These interactions appear to produce the preference for N-acetylgalactosamine over galactose and are also likely to influence the pK(a) of His(202). Protonation of His(202) would disrupt its interaction with an asparagine that serves as a ligand for Ca(2+) and sugar. The structure of the modified CRD without sugar displays several different conformations that may represent structures of intermediates in the release of Ca(2+) and sugar ligands caused by protonation of His(202).
About this Structure
1FIF is a Single protein structure of sequence from Rattus norvegicus. Full crystallographic information is available from OCA.
Reference
Mechanism of pH-dependent N-acetylgalactosamine binding by a functional mimic of the hepatocyte asialoglycoprotein receptor., Feinberg H, Torgersen D, Drickamer K, Weis WI, J Biol Chem. 2000 Nov 10;275(45):35176-84. PMID:10931846
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