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1eu4
From Proteopedia
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|PDB= 1eu4 |SIZE=350|CAPTION= <scene name='initialview01'>1eu4</scene>, resolution 2.50Å | |PDB= 1eu4 |SIZE=350|CAPTION= <scene name='initialview01'>1eu4</scene>, resolution 2.50Å | ||
|SITE= | |SITE= | ||
| - | |LIGAND= <scene name='pdbligand=ZN:ZINC ION'>ZN</scene> | + | |LIGAND= <scene name='pdbligand=ZN:ZINC+ION'>ZN</scene> |
|ACTIVITY= | |ACTIVITY= | ||
|GENE= | |GENE= | ||
| + | |DOMAIN= | ||
| + | |RELATEDENTRY=[[1et6|1ET6]], [[1et9|1ET9]], [[1eu3|1EU3]] | ||
| + | |RESOURCES=<span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1eu4 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1eu4 OCA], [http://www.ebi.ac.uk/pdbsum/1eu4 PDBsum], [http://www.rcsb.org/pdb/explore.do?structureId=1eu4 RCSB]</span> | ||
}} | }} | ||
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[[Category: Proft, T.]] | [[Category: Proft, T.]] | ||
[[Category: Sigrell, J A.]] | [[Category: Sigrell, J A.]] | ||
| - | [[Category: ZN]] | ||
[[Category: beta grasp]] | [[Category: beta grasp]] | ||
[[Category: ob fold]] | [[Category: ob fold]] | ||
[[Category: superantigen fold]] | [[Category: superantigen fold]] | ||
| - | ''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 20:09:42 2008'' |
Revision as of 17:09, 30 March 2008
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| , resolution 2.50Å | |||||||
|---|---|---|---|---|---|---|---|
| Ligands: | |||||||
| Related: | 1ET6, 1ET9, 1EU3
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| Resources: | FirstGlance, OCA, PDBsum, RCSB | ||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||
CRYSTAL STRUCTURE OF THE SUPERANTIGEN SPE-H (ZINC BOUND) FROM STREPTOCOCCUS PYOGENES
Overview
Bacterial superantigens (SAgs) are a structurally related group of protein toxins secreted by Staphylococcus aureus and Streptococcus pyogenes. They are implicated in a range of human pathologies associated with bacterial infection whose symptoms result from SAg-mediated stimulation of a large number (2-20%) of T-cells. At the molecular level, bacterial SAgs bind to major histocompatability class II (MHC-II) molecules and disrupt the normal interaction between MHC-II and T-cell receptors (TCRs). We have determined high-resolution crystal structures of two newly identified streptococcal superantigens, SPE-H and SMEZ-2. Both structures conform to the generic bacterial superantigen folding pattern, comprising an OB-fold N-terminal domain and a beta-grasp C-terminal domain. SPE-H and SMEZ-2 also display very similar zinc-binding sites on the outer concave surfaces of their C-terminal domains. Structural comparisons with other SAgs identify two structural sub-families. Sub-families are related by conserved core residues and demarcated by variable binding surfaces for MHC-II and TCR. SMEZ-2 is most closely related to the streptococcal SAg SPE-C, and together they constitute one structural sub-family. In contrast, SPE-H appears to be a hybrid whose N-terminal domain is most closely related to the SEB sub-family and whose C-terminal domain is most closely related to the SPE-C/SMEZ-2 sub-family. MHC-II binding for both SPE-H and SMEZ-2 is mediated by the zinc ion at their C-terminal face, whereas the generic N-terminal domain MHC-II binding site found on many SAgs appears not to be present. Structural comparisons provide evidence for variations in TCR binding between SPE-H, SMEZ-2 and other members of the SAg family; the extreme potency of SMEZ-2 (active at 10(-15) g ml-1 levels) is likely to be related to its TCR binding properties. The smez gene shows allelic variation that maps onto a considerable proportion of the protein surface. This allelic variation, coupled with the varied binding modes of SAgs to MHC-II and TCR, highlights the pressure on SAgs to avoid host immune defences.
About this Structure
1EU4 is a Single protein structure of sequence from Streptococcus pyogenes. Full crystallographic information is available from OCA.
Reference
Conservation and variation in superantigen structure and activity highlighted by the three-dimensional structures of two new superantigens from Streptococcus pyogenes., Arcus VL, Proft T, Sigrell JA, Baker HM, Fraser JD, Baker EN, J Mol Biol. 2000 May 26;299(1):157-68. PMID:10860729
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