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1sra
From Proteopedia
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| , resolution 2.0Å | |||||||
|---|---|---|---|---|---|---|---|
| Ligands: | |||||||
| Gene: | HUMAN BM-40 (Homo sapiens) | ||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||
STRUCTURE OF A NOVEL EXTRACELLULAR CA2+-BINDING MODULE IN BM-40(SLASH)SPARC(SLASH)OSTEONECTIN
Overview
The EF-hand is a highly conserved Ca(2+)-binding motif found in many cytosolic Ca(2+)-modulated proteins. Here we report the crystal structure at 2.0 A resolution of the carboxy-terminal domain of human BM-40 (SPARC, osteonectin), an extracellular matrix protein containing an EF-hand pair. The two EF-hands interact canonically but their detailed structures are unusual. In the first EF-hand a one-residue insertion is accommodated by a cis-peptide bond and by substituting a carboxylate by a peptide carbonyl as a Ca2+ ligand. The second EF-hand is stabilized by a disulphide bond. The EF-hand pair interacts tightly with an amphiphilic amino-terminal helix, reminiscent of target peptide binding by calmodulin. The present structure defines a novel protein module occurring in several other extracellular proteins.
About this Structure
1SRA is a Single protein structure of sequence from Homo sapiens. Full crystallographic information is available from OCA.
Reference
Structure of a novel extracellular Ca(2+)-binding module in BM-40., Hohenester E, Maurer P, Hohenadl C, Timpl R, Jansonius JN, Engel J, Nat Struct Biol. 1996 Jan;3(1):67-73. PMID:8548457
Page seeded by OCA on Thu Mar 20 14:08:42 2008
