1ews
From Proteopedia
THE THREE-DIMENSIONAL SOLUTION STRUCTURE OF THE RABBIT KIDNEY DEFENSIN, RK-1
Overview
NMR spectroscopy and simulated annealing calculations have been used to determine the three-dimensional structure of RK-1, an antimicrobial peptide from rabbit kidney recently discovered from homology screening based on the distinctive physicochemical properties of the corticostatins/defensins. RK-1 consists of 32 residues, including six cysteines arranged into three disulfide bonds. It exhibits antimicrobial activity against Escherichia coli and activates Ca(2+) channels in vitro. Through its physicochemical similarity, identical cysteine spacing, and linkage to the corticostatins/defensins, it was presumed to be a member of this family. However, RK-1 lacks both a large number of arginines in the primary sequence and a high overall positive charge, which are characteristic of this family of peptides. The three-dimensional solution structure, determined by NMR, consists of a triple-stranded antiparallel beta-sheet and a series of turns and is similar to the known structures of other alpha-defensins. This has enabled the definitive classification of RK-1 as a member of this family of antimicrobial peptides. Ultracentrifuge measurements confirmed that like rabbit neutrophil defensins, RK-1 is monomeric in solution, in contrast to human neutrophil defensins, which are dimeric.
About this Structure
1EWS is a Single protein structure of sequence from Oryctolagus cuniculus. Full crystallographic information is available from OCA.
Reference
Three-dimensional structure of RK-1: a novel alpha-defensin peptide., McManus AM, Dawson NF, Wade JD, Carrington LE, Winzor DJ, Craik DJ, Biochemistry. 2000 Dec 26;39(51):15757-64. PMID:11123900 Page seeded by OCA on Fri May 2 15:36:35 2008
