1ugx: Difference between revisions
New page: left|200px<br /><applet load="1ugx" size="450" color="white" frame="true" align="right" spinBox="true" caption="1ugx, resolution 1.60Å" /> '''Crystal structure of... |
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[[Image:1ugx.gif|left|200px]]<br /><applet load="1ugx" size=" | [[Image:1ugx.gif|left|200px]]<br /><applet load="1ugx" size="350" color="white" frame="true" align="right" spinBox="true" | ||
caption="1ugx, resolution 1.60Å" /> | caption="1ugx, resolution 1.60Å" /> | ||
'''Crystal structure of jacalin- Me-alpha-T-antigen (Gal-beta(1-3)-GalNAc-alpha-o-Me) complex'''<br /> | '''Crystal structure of jacalin- Me-alpha-T-antigen (Gal-beta(1-3)-GalNAc-alpha-o-Me) complex'''<br /> | ||
==Overview== | ==Overview== | ||
The structures of the complexes of tetrameric jacalin with Gal, Me-alpha-GalNAc, Me-alpha-T-antigen, GalNAcbeta1-3Gal-alpha-O-Me and | The structures of the complexes of tetrameric jacalin with Gal, Me-alpha-GalNAc, Me-alpha-T-antigen, GalNAcbeta1-3Gal-alpha-O-Me and Galalpha1-6Glc (mellibiose) show that the sugar-binding site of jacalin has three components: the primary site, secondary site A, and secondary site B. In these structures and in the two structures reported earlier, Gal or GalNAc occupy the primary site with the anomeric carbon pointing towards secondary site A. The alpha-substituents, when present, interact, primarily hydrophobically, with secondary site A which has variable geometry. O-H..., centered pi and C-H...pi hydrogen bonds involving this site also exist. On the other hand, beta-substitution leads to severe steric clashes. Therefore, in complexes involving beta-linked disaccharides, the reducing sugar binds at the primary site with the non-reducing end located at secondary site B. The interactions at secondary site B are primarily through water bridges. Thus, the nature of the linkage determines the mode of the association of the sugar with jacalin. The interactions observed in the crystal structures and modeling based on them provide a satisfactory qualitative explanation of the available thermodynamic data on jacalin-carbohydrate interactions. They also lead to fresh insights into the nature of the binding of glycoproteins by jacalin. | ||
==About this Structure== | ==About this Structure== | ||
1UGX is a [http://en.wikipedia.org/wiki/Protein_complex Protein complex] structure of sequences from [http://en.wikipedia.org/wiki/Artocarpus_integrifolia Artocarpus integrifolia]. Full crystallographic information is available from [http:// | 1UGX is a [http://en.wikipedia.org/wiki/Protein_complex Protein complex] structure of sequences from [http://en.wikipedia.org/wiki/Artocarpus_integrifolia Artocarpus integrifolia]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1UGX OCA]. | ||
==Reference== | ==Reference== | ||
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[[Category: Artocarpus integrifolia]] | [[Category: Artocarpus integrifolia]] | ||
[[Category: Protein complex]] | [[Category: Protein complex]] | ||
[[Category: Jeyaprakash, A | [[Category: Jeyaprakash, A A.]] | ||
[[Category: Katiyar, S.]] | [[Category: Katiyar, S.]] | ||
[[Category: Sekar, K.]] | [[Category: Sekar, K.]] | ||
[[Category: Surolia, A.]] | [[Category: Surolia, A.]] | ||
[[Category: Swaminathan, C | [[Category: Swaminathan, C P.]] | ||
[[Category: Vijayan, M.]] | [[Category: Vijayan, M.]] | ||
[[Category: all beta sheet protein]] | [[Category: all beta sheet protein]] | ||
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[[Category: galactose-specific]] | [[Category: galactose-specific]] | ||
''Page seeded by [http:// | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 15:24:21 2008'' | ||
Revision as of 16:24, 21 February 2008
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Crystal structure of jacalin- Me-alpha-T-antigen (Gal-beta(1-3)-GalNAc-alpha-o-Me) complex
OverviewOverview
The structures of the complexes of tetrameric jacalin with Gal, Me-alpha-GalNAc, Me-alpha-T-antigen, GalNAcbeta1-3Gal-alpha-O-Me and Galalpha1-6Glc (mellibiose) show that the sugar-binding site of jacalin has three components: the primary site, secondary site A, and secondary site B. In these structures and in the two structures reported earlier, Gal or GalNAc occupy the primary site with the anomeric carbon pointing towards secondary site A. The alpha-substituents, when present, interact, primarily hydrophobically, with secondary site A which has variable geometry. O-H..., centered pi and C-H...pi hydrogen bonds involving this site also exist. On the other hand, beta-substitution leads to severe steric clashes. Therefore, in complexes involving beta-linked disaccharides, the reducing sugar binds at the primary site with the non-reducing end located at secondary site B. The interactions at secondary site B are primarily through water bridges. Thus, the nature of the linkage determines the mode of the association of the sugar with jacalin. The interactions observed in the crystal structures and modeling based on them provide a satisfactory qualitative explanation of the available thermodynamic data on jacalin-carbohydrate interactions. They also lead to fresh insights into the nature of the binding of glycoproteins by jacalin.
About this StructureAbout this Structure
1UGX is a Protein complex structure of sequences from Artocarpus integrifolia. Full crystallographic information is available from OCA.
ReferenceReference
Structural basis of the carbohydrate specificities of jacalin: an X-ray and modeling study., Jeyaprakash AA, Katiyar S, Swaminathan CP, Sekar K, Surolia A, Vijayan M, J Mol Biol. 2003 Sep 5;332(1):217-28. PMID:12946359
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