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1esf
From Proteopedia
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STAPHYLOCOCCAL ENTEROTOXIN A
Overview
Staphylococcal enterotoxins are prototype superantigens characterized by, their ability to bind to major histocompatibility complex (MHC) class II, molecules and subsequently activate a large fraction of T-lymphocytes. The, crystal structure of staphylococcal enterotoxin type A (SEA), a 27 kDa, monomeric protein, was determined to 1.9 A resolution with an R-factor of, 19.9% by multiple isomorphous replacement. SEA is a two domain protein, composed of a beta-barrel and a beta-grasp motif demonstrating the same, general structure as staphylococcal enterotoxins SEB and TSST-1. Unique, for SEA, however, is a Zn2+ coordination site involved in MHC class II, binding. Four amino acids including Ser1, His187, His225 and Asp227 were, found to be involved in direct coordination of the metal ion. SEA is the, first Zn2+ binding enterotoxin that has been structurally determined.
About this Structure
1ESF is a Single protein structure of sequence from Staphylococcus aureus with CD as ligand. Structure known Active Sites: CD1 and CD2. Full crystallographic information is available from OCA.
Reference
Crystal structure of the superantigen staphylococcal enterotoxin type A., Schad EM, Zaitseva I, Zaitsev VN, Dohlsten M, Kalland T, Schlievert PM, Ohlendorf DH, Svensson LA, EMBO J. 1995 Jul 17;14(14):3292-301. PMID:7628431
Page seeded by OCA on Mon Nov 5 14:59:09 2007
