1scy: Difference between revisions

Revision as of 15:03, 20 March 2008

Ligands:

Coordinates:

DETERMINATION OF THE THREE-DIMENSIONAL STRUCTURE OF SCYLLATOXIN BY 1H NUCLEAR MAGNETIC RESONANCE

OverviewOverview

The three-dimensional solution structure of Scyllatoxin (leiurotoxin I) a venom peptide from the scorpion Leiurus quinquestriatus hebraeus was determined at 1 A resolution by homonuclear proton n.m.r. methods at 500 MHz. Data analysis and structure calculation followed conventional protocols inherent to DIANA and related programs with two exceptions. First, distance constraints were obtained from two-dimensional nuclear Overhauser spectra by a previously described partial relaxation matrix approach. Second, since the pairing pattern of the six cysteine residues was not established a priori, the unequivocal assignment of the disulfide bridges was achieved exclusively from the n.m.r. data by a statistical analysis of preliminary DIANA structures. In the final calculation we used 227 upper distance constraints, 67 torsional constraints from vicinal coupling constants and ten stereospecific assignments of beta-methylene protons. Scyllatoxin folds into a compact ellipsoidal shape. An alpha-helix (defined with 0.24 A resolution) spanning 2.5 turns from Leu5 till Ser14 is stabilized by Cys8-Cys26 and Cys12-Cys28 disulfide bridges to the carboxy-terminal strand of an anti-parallel beta-sheet. The antiparallel beta-sheet (defined at 0.66 A resolution) extends from Leu18 to Val29 with a tight turn at Gly23-Asp24 and displays a right-handed twist. Scyllatoxin competes with the toxins apamin from Apis mellifera mellifera and P05 from Androctonus mauretanicus mauretanicus for the same or similar high conductance calcium-activated potassium channels. Consideration of presently known biological activities and three-dimensional structures of these toxins suggest a different toxin-receptor interaction of scyllatoxin as compared to apamin and P05.

About this StructureAbout this Structure

1SCY is a Single protein structure of sequence from Leiurus quinquestriatus hebraeus. Full crystallographic information is available from OCA.

ReferenceReference

Determination of the three-dimensional solution structure of scyllatoxin by 1H nuclear magnetic resonance., Martins JC, Van de Ven FJ, Borremans FA, J Mol Biol. 1995 Nov 3;253(4):590-603. PMID:7473736

Page seeded by OCA on Thu Mar 20 14:03:20 2008

Proteopedia Page Contributors and Editors (what is this?)Proteopedia Page Contributors and Editors (what is this?)

OCA

@@ Line 1: / Line 1: @@
-[[Image:1scy.gif|left|200px]]<br /><applet load="1scy" size="350" color="white" frame="true" align="right" spinBox="true"
+[[Image:1scy.gif|left|200px]]
-caption="1scy" />
-'''DETERMINATION OF THE THREE-DIMENSIONAL STRUCTURE OF SCYLLATOXIN BY 1H NUCLEAR MAGNETIC RESONANCE'''<br />
+ {{Structure
+|PDB= 1scy |SIZE=350|CAPTION= <scene name='initialview01'>1scy</scene>
+|SITE=
+|LIGAND= <scene name='pdbligand=NH2:AMINO GROUP'>NH2</scene>
+|ACTIVITY=
+|GENE=
+}}
+'''DETERMINATION OF THE THREE-DIMENSIONAL STRUCTURE OF SCYLLATOXIN BY 1H NUCLEAR MAGNETIC RESONANCE'''
 ==Overview==
@@ Line 7: / Line 16: @@
 ==About this Structure==
-SCY is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Leiurus_quinquestriatus_hebraeus Leiurus quinquestriatus hebraeus] with <scene name='pdbligand=NH2:'>NH2</scene> as [http://en.wikipedia.org/wiki/ligand ligand]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1SCY OCA].
+SCY is a [[Single protein]] structure of sequence from [http://en.wikipedia.org/wiki/Leiurus_quinquestriatus_hebraeus Leiurus quinquestriatus hebraeus]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1SCY OCA].
 ==Reference==
-Determination of the three-dimensional solution structure of scyllatoxin by 1H nuclear magnetic resonance., Martins JC, Van de Ven FJ, Borremans FA, J Mol Biol. 1995 Nov 3;253(4):590-603. PMID:[http://ispc.weizmann.ac.il//pmbin/getpm?pmid=7473736 7473736]
+Determination of the three-dimensional solution structure of scyllatoxin by 1H nuclear magnetic resonance., Martins JC, Van de Ven FJ, Borremans FA, J Mol Biol. 1995 Nov 3;253(4):590-603. PMID:[http://www.ncbi.nlm.nih.gov/pubmed/7473736 7473736]
 [[Category: Leiurus quinquestriatus hebraeus]]
 [[Category: Single protein]]
@@ Line 19: / Line 28: @@
 [[Category: neurotoxin]]
-''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 15:00:15 2008''
+''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Mar 20 14:03:20 2008''