1ccd
From Proteopedia
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REFINED STRUCTURE OF RAT CLARA CELL 17 KDA PROTEIN AT 3.0 ANGSTROMS RESOLUTION
Overview
The rat Clara cell 17 kDa protein (previously referred to as the rat Clara, cell 10 kDa protein) has been reported to inhibit phospholipase A2 and, papain, and to also bind progesterone. It has been isolated from rat lung, lavage fluid and crystallized in the space group P6(5)22. The structure, has been determined to 3.0 A resolution using the molecular replacement, method. Uteroglobin, whose amino acid sequence is 55.7% identical, was, used as the search model. The structure was then refined using restrained, least-squares and simulated annealing methods. The R-factor is 22.5%. The, protein is a covalently bound dimer. Two disulfide bonds join the monomers, together in an antiparallel manner such that the dimer encloses a large, internal hydrophobic cavity. The hydrophobic cavity is large enough to, serve as the progesterone binding site, but access to the cavity is, limited. Each monomer is composed of four alpha-helices. The main-chain, structure of the Clara cell protein closely resembles that of uteroglobin, but the nature of many of the exposed side-chains differ. This is true, particularly in a hypervariable region between residues 23 and 36, and in, the H1H4 pocket.
About this Structure
1CCD is a Single protein structure of sequence from Rattus rattus with SO4 as ligand. Full crystallographic information is available from OCA.
Reference
Refined structure of rat Clara cell 17 kDa protein at 3.0 A resolution., Umland TC, Swaminathan S, Furey W, Singh G, Pletcher J, Sax M, J Mol Biol. 1992 Mar 20;224(2):441-8. PMID:1560460
Page seeded by OCA on Tue Nov 20 12:20:37 2007
