2dtw: Difference between revisions
New page: left|200px<br /><applet load="2dtw" size="450" color="white" frame="true" align="right" spinBox="true" caption="2dtw, resolution 2.40Å" /> '''Crystal Structure of... |
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[[Image:2dtw.gif|left|200px]]<br /><applet load="2dtw" size=" | [[Image:2dtw.gif|left|200px]]<br /><applet load="2dtw" size="350" color="white" frame="true" align="right" spinBox="true" | ||
caption="2dtw, resolution 2.40Å" /> | caption="2dtw, resolution 2.40Å" /> | ||
'''Crystal Structure of basic winged bean lectin in complex with 2Me-O-D-Galactose'''<br /> | '''Crystal Structure of basic winged bean lectin in complex with 2Me-O-D-Galactose'''<br /> | ||
==Overview== | ==Overview== | ||
The crystal structure of the complexes of basic winged-bean lectin with | The crystal structure of the complexes of basic winged-bean lectin with galactose, 2-methoxygalactose, N-acetylgalactosamine and methyl-alpha-N-acetylgalactosamine have been determined. Lectin-sugar interactions involve four hydrogen bonds and a stacking interaction in all of the complexes. In addition, an N-H...O hydrogen bond involving the hydroxyl group at C2 exists in the galactose and 2-methoxygalactose complexes. An additional hydrophobic interaction involving the methyl group in the latter leads to the higher affinity of the methyl derivative. In the lectin-N-acetylgalactosamine complex the N-H...O hydrogen bond is lost, but a compensatory hydrogen bond is formed involving the O atom of the acetamido group. In addition, the CH(3) moiety of the acetamido group is involved in hydrophobic interactions. Consequently, the 2-methyl and acetamido derivatives of galactose have nearly the same affinity for the lectin. The methyl group alpha-linked to the galactose takes part in additional hydrophobic interactions. Therefore, methyl-alpha-N-acetylgalactosamine has a higher affinity than N-acetylgalactosamine for the lectin. The structures of basic winged-bean lectin-sugar complexes provide a framework for examining the relative affinity of galactose and galactosamine for the lectins that bind to them. The complexes also lead to a structural explanation for the blood-group specificity of basic winged-bean lectin. | ||
==About this Structure== | ==About this Structure== | ||
2DTW is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Psophocarpus_tetragonolobus Psophocarpus tetragonolobus] with 2GS, NAG, CA and MN as [http://en.wikipedia.org/wiki/ligands ligands]. Full crystallographic information is available from [http:// | 2DTW is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Psophocarpus_tetragonolobus Psophocarpus tetragonolobus] with <scene name='pdbligand=2GS:'>2GS</scene>, <scene name='pdbligand=NAG:'>NAG</scene>, <scene name='pdbligand=CA:'>CA</scene> and <scene name='pdbligand=MN:'>MN</scene> as [http://en.wikipedia.org/wiki/ligands ligands]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2DTW OCA]. | ||
==Reference== | ==Reference== | ||
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[[Category: Single protein]] | [[Category: Single protein]] | ||
[[Category: Katiyar, S.]] | [[Category: Katiyar, S.]] | ||
[[Category: Kulkarni, K | [[Category: Kulkarni, K A.]] | ||
[[Category: Suguna, K.]] | [[Category: Suguna, K.]] | ||
[[Category: Surolia, A.]] | [[Category: Surolia, A.]] | ||
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[[Category: legume lectin]] | [[Category: legume lectin]] | ||
''Page seeded by [http:// | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 17:02:36 2008'' | ||
Revision as of 18:02, 21 February 2008
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Crystal Structure of basic winged bean lectin in complex with 2Me-O-D-Galactose
OverviewOverview
The crystal structure of the complexes of basic winged-bean lectin with galactose, 2-methoxygalactose, N-acetylgalactosamine and methyl-alpha-N-acetylgalactosamine have been determined. Lectin-sugar interactions involve four hydrogen bonds and a stacking interaction in all of the complexes. In addition, an N-H...O hydrogen bond involving the hydroxyl group at C2 exists in the galactose and 2-methoxygalactose complexes. An additional hydrophobic interaction involving the methyl group in the latter leads to the higher affinity of the methyl derivative. In the lectin-N-acetylgalactosamine complex the N-H...O hydrogen bond is lost, but a compensatory hydrogen bond is formed involving the O atom of the acetamido group. In addition, the CH(3) moiety of the acetamido group is involved in hydrophobic interactions. Consequently, the 2-methyl and acetamido derivatives of galactose have nearly the same affinity for the lectin. The methyl group alpha-linked to the galactose takes part in additional hydrophobic interactions. Therefore, methyl-alpha-N-acetylgalactosamine has a higher affinity than N-acetylgalactosamine for the lectin. The structures of basic winged-bean lectin-sugar complexes provide a framework for examining the relative affinity of galactose and galactosamine for the lectins that bind to them. The complexes also lead to a structural explanation for the blood-group specificity of basic winged-bean lectin.
About this StructureAbout this Structure
2DTW is a Single protein structure of sequence from Psophocarpus tetragonolobus with , , and as ligands. Full crystallographic information is available from OCA.
ReferenceReference
Structural basis for the carbohydrate-specificity of basic winged-bean lectin and its differential affinity for Gal and GalNAc., Kulkarni KA, Katiyar S, Surolia A, Vijayan M, Suguna K, Acta Crystallogr D Biol Crystallogr. 2006 Nov;62(Pt 11):1319-24. Epub 2006, Oct 18. PMID:17057334
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