1wvr
From Proteopedia
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| , resolution 2.40Å | |||||||
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| Ligands: | |||||||
| Resources: | FirstGlance, OCA, PDBsum, RCSB | ||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||
Crystal Structure of a CRISP family Ca-channel blocker derived from snake venom
Overview
The cysteine-rich secretory proteins (CRISPs) are widely distributed in mammals, reptiles, amphibians and secernenteas, and are involved in a variety of biological reactions. Here we report the crystal structure of triflin, a snake venom derived blocker of high K(+)-induced artery contraction, at 2.4A resolution. Triflin consists of two domains. The first 163 residues form a large globular body with an alpha-beta-alpha sandwich core, which resembles pathogenesis-related proteins of group-1 (PR-1). Two glutamic acid-associated histidine residues are located in an elongated cleft. A Cd(2+) resides in this binding site, and forms a five-coordination sphere. The subsequent cysteine-rich domain adopts a rod-like shape, which is stabilized by five disulfide bridges. Hydrophobic residues, which may obstruct the target ion-channel, are exposed to the solvent. A concave surface, which is surrounded by these two domains, is also expected to play a significant role in the binding to the target receptor, leading to ion channel blockage. The C-terminal cysteine-rich region has a similar tertiary structure to voltage-gated potassium channel blocker toxins, such as BgK and ShK. These findings will contribute toward understanding the functions of the widely distributed CRISP family proteins.
About this Structure
1WVR is a Single protein structure of sequence from Trimeresurus flavoviridis. Full crystallographic information is available from OCA.
Reference
Crystal structure of a CRISP family Ca2+ -channel blocker derived from snake venom., Shikamoto Y, Suto K, Yamazaki Y, Morita T, Mizuno H, J Mol Biol. 2005 Jul 22;350(4):735-43. PMID:15953617
Page seeded by OCA on Mon Mar 31 00:41:38 2008
