1hnf
From Proteopedia
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CRYSTAL STRUCTURE OF THE EXTRACELLULAR REGION OF THE HUMAN CELL ADHESION MOLECULE CD2 AT 2.5 ANGSTROMS RESOLUTION
Overview
BACKGROUND: The T-lymphocyte antigen CD2 is an adhesion molecule, implicated in immune responses in vivo. The extracellular regions of the, human and rat homologues of CD2 share only 45% sequence identity and bind, different protein ligands. Comparison of the human and rat soluble CD2, (sCD2) structures should provide insights into the structural basis of, cell surface recognition. RESULTS: We therefore determined the crystal, structure of a form of human sCD2 with single N-acetylglucosamine residues, at each glycosylation site to 2.5 A resolution with an R-factor of 19.3%., It is composed of two immunoglobulin superfamily domains similar to those, of rat sCD2, but the relative orientation of the domains in the two, homologues differs by up to 20 degrees. An interaction involving the flat, highly charged, ligand binding GFCC'C" faces of crystallographically, related human sCD2 molecules duplicates, in a different lattice, that, observed in the rat sCD2 crystals. CONCLUSIONS: Intramolecular flexibility, appears to be a conserved feature of CD2. The head-to-head interaction, between molecules represents a general model for interactions between, adhesion molecules of this structural class. Ligand specificity may be, influenced by the distribution of charged residues on the binding face.
About this Structure
1HNF is a Single protein structure of sequence from Homo sapiens with NAG and NA as ligands. Full crystallographic information is available from OCA.
Reference
Crystal structure of the extracellular region of the human cell adhesion molecule CD2 at 2.5 A resolution., Bodian DL, Jones EY, Harlos K, Stuart DI, Davis SJ, Structure. 1994 Aug 15;2(8):755-66. PMID:7994575
Page seeded by OCA on Mon Nov 12 17:20:37 2007
