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1kba
From Proteopedia
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| - | [[Image:1kba.jpg|left|200px]] | + | [[Image:1kba.jpg|left|200px]] |
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| - | '''CRYSTAL STRUCTURE OF KAPPA-BUNGAROTOXIN AT 2.3-ANGSTROM RESOLUTION''' | + | {{Structure |
| + | |PDB= 1kba |SIZE=350|CAPTION= <scene name='initialview01'>1kba</scene>, resolution 2.3Å | ||
| + | |SITE= | ||
| + | |LIGAND= | ||
| + | |ACTIVITY= | ||
| + | |GENE= | ||
| + | }} | ||
| + | |||
| + | '''CRYSTAL STRUCTURE OF KAPPA-BUNGAROTOXIN AT 2.3-ANGSTROM RESOLUTION''' | ||
| + | |||
==Overview== | ==Overview== | ||
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==About this Structure== | ==About this Structure== | ||
| - | 1KBA is a [ | + | 1KBA is a [[Single protein]] structure of sequence from [http://en.wikipedia.org/wiki/Bungarus_multicinctus Bungarus multicinctus]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1KBA OCA]. |
==Reference== | ==Reference== | ||
| - | Crystal structure of kappa-bungarotoxin at 2.3-A resolution., Dewan JC, Grant GA, Sacchettini JC, Biochemistry. 1994 Nov 8;33(44):13147-54. PMID:[http:// | + | Crystal structure of kappa-bungarotoxin at 2.3-A resolution., Dewan JC, Grant GA, Sacchettini JC, Biochemistry. 1994 Nov 8;33(44):13147-54. PMID:[http://www.ncbi.nlm.nih.gov/pubmed/7947721 7947721] |
[[Category: Bungarus multicinctus]] | [[Category: Bungarus multicinctus]] | ||
[[Category: Single protein]] | [[Category: Single protein]] | ||
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[[Category: toxin]] | [[Category: toxin]] | ||
| - | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Mar 20 12:15:01 2008'' |
Revision as of 10:15, 20 March 2008
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| Coordinates: | save as pdb, mmCIF, xml | ||||||
CRYSTAL STRUCTURE OF KAPPA-BUNGAROTOXIN AT 2.3-ANGSTROM RESOLUTION
Overview
kappa-Neurotoxins display a very low affinity for neuromuscular receptors, but bind tightly to, and inhibit, nicotinic acetylcholine receptors in neuronal tissue such as the chick ciliary ganglia. In contrast, alpha-neurotoxins bind with high affinity and inhibit nicotinic acetylcholine receptors at the neuromuscular junction. The origin of this difference in specificity has been a long-studied question in the field. Here we report the first crystal structure of a kappa-neurotoxin, kappa-bungarotoxin. Unlike the NMR structure previously reported [Sutcliffe, M. J., Dobson, C. M., & Oswald, R. E. (1992) Biochemistry 31, 2962-2970], the present crystal structure more accurately defines the polypeptide fold and the nature of the interaction between subunits in the active dimer, which is a unique feature of the kappa-neurotoxins. The structure has been refined to R = 19.6% with X-ray diffraction data extending to a resolution of 2.3 A. There are two independent protein molecules (66 amino acid residues each) in the asymmetric unit that are arranged as a dimer with the two subunits related by a rotation of 178.6 degrees. Each subunit consists of three main-chain loops. Three of the five beta-strands of each subunit form an antiparallel beta-sheet which becomes an extended six-stranded antiparallel beta-sheet, by virtue of the approximate 2-fold symmetry of the dimer. The interactions at the dimer interface consist of six main-chain-main-chain hydrogen bonds, as well as three other hydrogen-bonding interactions involving side chains.(ABSTRACT TRUNCATED AT 250 WORDS)
About this Structure
1KBA is a Single protein structure of sequence from Bungarus multicinctus. Full crystallographic information is available from OCA.
Reference
Crystal structure of kappa-bungarotoxin at 2.3-A resolution., Dewan JC, Grant GA, Sacchettini JC, Biochemistry. 1994 Nov 8;33(44):13147-54. PMID:7947721
Page seeded by OCA on Thu Mar 20 12:15:01 2008
