1rdk
From Proteopedia
(New page: 200px<br /><applet load="1rdk" size="450" color="white" frame="true" align="right" spinBox="true" caption="1rdk, resolution 1.8Å" /> '''MANNOSE-BINDING PROTE...) |
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| - | [[Image:1rdk.jpg|left|200px]]<br /><applet load="1rdk" size=" | + | [[Image:1rdk.jpg|left|200px]]<br /><applet load="1rdk" size="350" color="white" frame="true" align="right" spinBox="true" |
caption="1rdk, resolution 1.8Å" /> | caption="1rdk, resolution 1.8Å" /> | ||
'''MANNOSE-BINDING PROTEIN, SUBTILISIN DIGEST FRAGMENT COMPLEX WITH D-GALACTOSE'''<br /> | '''MANNOSE-BINDING PROTEIN, SUBTILISIN DIGEST FRAGMENT COMPLEX WITH D-GALACTOSE'''<br /> | ||
==Overview== | ==Overview== | ||
| - | The structural basis of carbohydrate recognition by rat liver | + | The structural basis of carbohydrate recognition by rat liver mannose-binding protein (MBP-C) has been explored by determining the three-dimensional structure of the C-type carbohydrate-recognition domain (CRD) of MBP-C using x-ray crystallography. The structure was solved by molecular replacement using rat serum mannose-binding protein (MBP-A) as a search model and was refined to maximum Bragg spacings of 1.7 A. Despite their almost identical folds, the dimeric structures formed by the two MBP CRDs differ dramatically. Complexes of MBP-C with methyl glycosides of mannose, N-acetylglucosamine, and fucose were prepared by soaking MBP-C crystals in solutions containing these sugars. Surprisingly, the pyranose ring of mannose is rotated 180 degrees relative to the orientation observed previously in MBP-A, but the local interactions between sugar and protein are preserved. For each of the bound sugars, vicinal, equatorial hydroxyl groups equivalent to the 3- and 4-OH groups of mannose directly coordinate Ca2+ and form hydrogen bonds with residues also serving as Ca2+ ligands. Few interactions are observed between other parts of the sugar and the protein. A complex formed between free galactose and MBP-C reveals a similar mode of binding, with the anomeric hydroxyl group serving as one of the Ca2+ ligands. A second binding site for mannose has also been observed in one of two copies in the asymmetric unit at a sugar concentration of 1.3 M. These structures explain how MBPs recognize a wide range of monosaccharides and suggest how fine specificity differences between MBP-A and MBP-C may be achieved. |
==About this Structure== | ==About this Structure== | ||
| - | 1RDK is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Rattus_rattus Rattus rattus] with GAL, CA and CL as [http://en.wikipedia.org/wiki/ligands ligands]. Full crystallographic information is available from [http:// | + | 1RDK is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Rattus_rattus Rattus rattus] with <scene name='pdbligand=GAL:'>GAL</scene>, <scene name='pdbligand=CA:'>CA</scene> and <scene name='pdbligand=CL:'>CL</scene> as [http://en.wikipedia.org/wiki/ligands ligands]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1RDK OCA]. |
==Reference== | ==Reference== | ||
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[[Category: Single protein]] | [[Category: Single protein]] | ||
[[Category: Drickamer, K.]] | [[Category: Drickamer, K.]] | ||
| - | [[Category: Ng, K | + | [[Category: Ng, K K.S.]] |
| - | [[Category: Weis, W | + | [[Category: Weis, W I.]] |
[[Category: CA]] | [[Category: CA]] | ||
[[Category: CL]] | [[Category: CL]] | ||
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[[Category: calcium-binding protein]] | [[Category: calcium-binding protein]] | ||
| - | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 14:49:42 2008'' |
Revision as of 12:49, 21 February 2008
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MANNOSE-BINDING PROTEIN, SUBTILISIN DIGEST FRAGMENT COMPLEX WITH D-GALACTOSE
Overview
The structural basis of carbohydrate recognition by rat liver mannose-binding protein (MBP-C) has been explored by determining the three-dimensional structure of the C-type carbohydrate-recognition domain (CRD) of MBP-C using x-ray crystallography. The structure was solved by molecular replacement using rat serum mannose-binding protein (MBP-A) as a search model and was refined to maximum Bragg spacings of 1.7 A. Despite their almost identical folds, the dimeric structures formed by the two MBP CRDs differ dramatically. Complexes of MBP-C with methyl glycosides of mannose, N-acetylglucosamine, and fucose were prepared by soaking MBP-C crystals in solutions containing these sugars. Surprisingly, the pyranose ring of mannose is rotated 180 degrees relative to the orientation observed previously in MBP-A, but the local interactions between sugar and protein are preserved. For each of the bound sugars, vicinal, equatorial hydroxyl groups equivalent to the 3- and 4-OH groups of mannose directly coordinate Ca2+ and form hydrogen bonds with residues also serving as Ca2+ ligands. Few interactions are observed between other parts of the sugar and the protein. A complex formed between free galactose and MBP-C reveals a similar mode of binding, with the anomeric hydroxyl group serving as one of the Ca2+ ligands. A second binding site for mannose has also been observed in one of two copies in the asymmetric unit at a sugar concentration of 1.3 M. These structures explain how MBPs recognize a wide range of monosaccharides and suggest how fine specificity differences between MBP-A and MBP-C may be achieved.
About this Structure
1RDK is a Single protein structure of sequence from Rattus rattus with , and as ligands. Full crystallographic information is available from OCA.
Reference
Structural analysis of monosaccharide recognition by rat liver mannose-binding protein., Ng KK, Drickamer K, Weis WI, J Biol Chem. 1996 Jan 12;271(2):663-74. PMID:8557671
Page seeded by OCA on Thu Feb 21 14:49:42 2008
Categories: Rattus rattus | Single protein | Drickamer, K. | Ng, K K.S. | Weis, W I. | CA | CL | GAL | C-type lectin | Calcium-binding protein
