1nap
From Proteopedia
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THE CRYSTAL STRUCTURE OF RECOMBINANT HUMAN NEUTROPHIL-ACTIVATING PEPTIDE-2 (M6L) AT 1.9-ANGSTROMS RESOLUTION
Overview
Neutrophil-activating peptide-2 (NAP-2) is a 70-residue carboxyl-terminal, fragment of platelet basic protein, which is found in the alpha-granules, of human platelets. NAP-2, which belongs to the CXC family of chemokines, that includes interleukin-8 and platelet factor 4, binds to the, interleukin-8 type II receptor and induces a rise in cytosolic calcium, chemotaxis of neutrophils, and exocytosis. Crystals of recombinant NAP-2, in which the single methionine at position 6 was replaced by leucine to, facilitate expression belong to space group P1 (unit cell parameters a =, 40.8, b = 43.8, and c = 44.7 A and alpha = 98.4 degrees, beta = 120.3, degrees, and gamma = 92.8 degrees), with 4 molecules of NAP-2 (Mr = 7600), in the asymmetric unit. The molecular replacement solution calculated with, bovine platelet factor 4 as the starting model was refined using rigid, body refinement, manual fitting in solvent-leveled electron density maps, simulated annealing, and restrained least squares to an R-factor of 0.188, for 2 sigma data between 7.0- and 1.9-A resolution. The final refined, crystal structure includes 265 solvent molecules. The overall tertiary, structure, which is similar to that of platelet factor 4 and, interleukin-8, includes an extended amino-terminal loop, three strands of, antiparallel beta-sheet arranged in a Greek key fold, and one alpha-helix, at the carboxyl terminus. The Glu-Leu-Arg sequence that is critical for, receptor binding is fully defined by electron density and exhibits, multiple conformations.
About this Structure
1NAP is a Single protein structure of sequence from Homo sapiens. Full crystallographic information is available from OCA.
Reference
The crystal structure of recombinant human neutrophil-activating peptide-2 (M6L) at 1.9-A resolution., Malkowski MG, Wu JY, Lazar JB, Johnson PH, Edwards BF, J Biol Chem. 1995 Mar 31;270(13):7077-87. PMID:7706245
Page seeded by OCA on Fri Feb 15 16:27:55 2008
