This old version of Proteopedia is provided for student assignments while the new version is undergoing repairs. Content and edits done in this old version of Proteopedia after March 1, 2026 will eventually be lost when it is retired in about June of 2026.
Apply for new accounts at the new Proteopedia. Your logins will work in both the old and new versions.
2ici
From Proteopedia
| Line 1: | Line 1: | ||
| - | [[Image:2ici.gif|left|200px]] | + | [[Image:2ici.gif|left|200px]] |
| - | + | ||
| - | '''Crystal Structure of Streptococcal Pyrogenic Exotoxin I''' | + | {{Structure |
| + | |PDB= 2ici |SIZE=350|CAPTION= <scene name='initialview01'>2ici</scene>, resolution 1.560Å | ||
| + | |SITE= | ||
| + | |LIGAND= <scene name='pdbligand=MG:MAGNESIUM ION'>MG</scene> | ||
| + | |ACTIVITY= | ||
| + | |GENE= speI ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=1314 Streptococcus pyogenes]) | ||
| + | }} | ||
| + | |||
| + | '''Crystal Structure of Streptococcal Pyrogenic Exotoxin I''' | ||
| + | |||
==Overview== | ==Overview== | ||
| Line 7: | Line 16: | ||
==About this Structure== | ==About this Structure== | ||
| - | 2ICI is a [ | + | 2ICI is a [[Single protein]] structure of sequence from [http://en.wikipedia.org/wiki/Streptococcus_pyogenes Streptococcus pyogenes]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2ICI OCA]. |
==Reference== | ==Reference== | ||
| - | Crystal structure of the streptococcal superantigen SpeI and functional role of a novel loop domain in T cell activation by group V superantigens., Brouillard JN, Gunther S, Varma AK, Gryski I, Herfst CA, Rahman AK, Leung DY, Schlievert PM, Madrenas J, Sundberg EJ, McCormick JK, J Mol Biol. 2007 Apr 6;367(4):925-34. Epub 2007 Jan 12. PMID:[http:// | + | Crystal structure of the streptococcal superantigen SpeI and functional role of a novel loop domain in T cell activation by group V superantigens., Brouillard JN, Gunther S, Varma AK, Gryski I, Herfst CA, Rahman AK, Leung DY, Schlievert PM, Madrenas J, Sundberg EJ, McCormick JK, J Mol Biol. 2007 Apr 6;367(4):925-34. Epub 2007 Jan 12. PMID:[http://www.ncbi.nlm.nih.gov/pubmed/17303163 17303163] |
[[Category: Single protein]] | [[Category: Single protein]] | ||
[[Category: Streptococcus pyogenes]] | [[Category: Streptococcus pyogenes]] | ||
| Line 19: | Line 28: | ||
[[Category: streptococcal superantigen spei]] | [[Category: streptococcal superantigen spei]] | ||
| - | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Mar 20 17:27:53 2008'' |
Revision as of 15:27, 20 March 2008
| |||||||
| , resolution 1.560Å | |||||||
|---|---|---|---|---|---|---|---|
| Ligands: | |||||||
| Gene: | speI (Streptococcus pyogenes) | ||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||
Crystal Structure of Streptococcal Pyrogenic Exotoxin I
Overview
Superantigens (SAgs) are potent microbial toxins that bind simultaneously to T cell receptors (TCRs) and class II major histocompatibility complex molecules, resulting in the activation and expansion of large T cell subsets and the onset of numerous human diseases. Within the bacterial SAg family, streptococcal pyrogenic exotoxin I (SpeI) has been classified as belonging to the group V SAg subclass, which are characterized by a unique, relatively conserved approximately 15 amino acid extension (amino acid residues 154 to 170 in SpeI; herein referred to as the alpha3-beta8 loop), absent in SAg groups I through IV. Here, we report the crystal structure of SpeI at 1.56 A resolution. Although the alpha3-beta8 loop in SpeI is several residues shorter than that of another group V SAg, staphylococcal enterotoxin serotype I, the C-terminal portions of these loops, which are located adjacent to the putative TCR binding site, are structurally similar. Mutagenesis and subsequent functional analysis of SpeI indicates that TCR beta-chains are likely engaged in a similar general orientation as other characterized SAgs. We show, however, that the alpha3-beta8 loop length, and the presence of key glycine residues, are necessary for optimal activation of T cells. Based on Vbeta-skewing analysis of human T cells activated with SpeI and structural models, we propose that the alpha3-beta8 loop is positioned to form productive intermolecular contacts with the TCR beta-chain, likely in framework region 3, and that these contacts are required for optimal TCR recognition by SpeI, and likely all other group V SAgs.
About this Structure
2ICI is a Single protein structure of sequence from Streptococcus pyogenes. Full crystallographic information is available from OCA.
Reference
Crystal structure of the streptococcal superantigen SpeI and functional role of a novel loop domain in T cell activation by group V superantigens., Brouillard JN, Gunther S, Varma AK, Gryski I, Herfst CA, Rahman AK, Leung DY, Schlievert PM, Madrenas J, Sundberg EJ, McCormick JK, J Mol Biol. 2007 Apr 6;367(4):925-34. Epub 2007 Jan 12. PMID:17303163
Page seeded by OCA on Thu Mar 20 17:27:53 2008
