View source for 1an8

[[Image:1an8.jpg|left|200px]]<br /><applet load="1an8" size="450" color="white" frame="true" align="right" spinBox="true" 
caption="1an8, resolution 2.4&Aring;" />
'''CRYSTAL STRUCTURE OF THE STREPTOCOCCAL SUPERANTIGEN SPE-C'''<br />

==Overview==
Bacterial superantigens are small proteins that have a very potent, stimulatory effect on T lymphocytes through their ability to bind to both, MHC class II molecules and T-cell receptors. We have determined the, three-dimensional structure of a Streptococcal superantigen, SPE-C, at 2.4, A resolution. The structure shows that SPE-C has the usual superantigen, fold, but that the surface that forms a generic, low-affinity MHC-binding, site in other superantigens is here used to create a SPE-C dimer. Instead, MHC class II binding occurs through a zinc binding site that is analogous, to a similar site in staphylococcal enterotoxin A. Consideration of the, SPE-C dimer suggests a novel mechanism for promotion of MHC aggregation, and T-cell activation.

==About this Structure==
1AN8 is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Streptococcus_pyogenes Streptococcus pyogenes]. Known structural/functional Sites: <scene name='pdbsite=ZNA:This Site Also Includes HIS 81 From A Symmetry-Related M ...'>ZNA</scene> and <scene name='pdbsite=ZNB:This Site Also Includes HIS 35 And GLU 54 From A Symmetr ...'>ZNB</scene>. Full crystallographic information is available from [http://ispc.weizmann.ac.il/oca-bin/ocashort?id=1AN8 OCA]. 

==Reference==
Crystal structure of the streptococcal superantigen SPE-C: dimerization and zinc binding suggest a novel mode of interaction with MHC class II molecules., Roussel A, Anderson BF, Baker HM, Fraser JD, Baker EN, Nat Struct Biol. 1997 Aug;4(8):635-43. PMID:[http://ispc.weizmann.ac.il//pmbin/getpm?pmid=9253413 9253413]
[[Category: Single protein]]
[[Category: Streptococcus pyogenes]]
[[Category: Baker, E.N.]]
[[Category: Roussel, A.]]
[[Category: bacterial superantigen]]
[[Category: toxin]]

''Page seeded by [http://ispc.weizmann.ac.il/oca OCA ] on Tue Dec 18 14:18:27 2007''