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1sco

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Revision as of 21:32, 10 September 2015

SCORPION TOXIN (OSK1 TOXIN) WITH HIGH AFFINITY FOR SMALL CONDUCTANCE CA(2+)-ACTIVATED K+ CHANNEL IN NEUROBLASTOMA-X-GLUOMA NG 108-15 HYBRID CELLS, NMR, 30 STRUCTURES

Structural highlights

1sco is a 1 chain structure with sequence from Orthochirus scrobiculosus. Full experimental information is available from OCA. For a guided tour on the structure components use FirstGlance.
Resources:	FirstGlance, OCA, PDBe, RCSB, PDBsum

Function

[KAX37_ORTSC] Blocks voltage-gated potassium channels Kv1.1/KCNA1 (IC(50)=0.6nM), Kv1.2/KCNA2 (IC(50)=5.4nM), Kv1.3/KCNA3 (IC(50)=0.014nM) potently, and moderately block intermediate conductance calcium-activated potassium channels KCa3.1/KCNN4 (IC(50)=225nM). At high concentration (2 mM), is also active on Kv1.6/KCNA6 and Shaker IR.[REFERENCE:1]^[1]

Evolutionary Conservation

Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf.

Publication Abstract from PubMed

A 600 MHz 1H NMR study of toxin OSK1, blocker of small-conductance Ca2+-activated K+ channels, is presented. The unambiguous sequential assignment of all the protons of the toxin was obtained using TOCSY, DQF-COSY, and NOESY experiments at pH 3.0 (10, 30, and 45 degrees C) in aqueous solution. 3J(N alpha), 3J(alphabeta) vicinal spin coupling constants were determined in high-resolution spectra. The cross-peak volumes in NOESY spectra and the coupling constants were used to define the local structure of the protein by the program HABAS and to generate torsion angle and interproton distance constraints for the program DIANA. Hydrogen-deuterium exchange rates of amide protons showed possible locations of hydrogen bonds. The hydrogen bond acceptors and disulfide bridges between residues 8-28, 14-33, and 18-35 were determined when analyzing distance distribution in preliminary DIANA structures. All constraints were used to obtain a set of 30 structures by DIANA. The resulting rms deviations over 30 structures are 1.30 A for the heavy atoms and 0.42 A for the backbone heavy atoms. The structures were refined by constrained energy minimization using the SYBYL program. Their analysis indicated the existence of the alpha-helix (residues 10-21) slightly distorted at the Cys14 residue, two main strands of the antiparallel beta-sheet (24-29, 32-38), and the extended fragment (2-6). The motif is stabilized by the disulfide bridges in the way, common to all known scorpion toxins. Using the fine spatial toxin structure, alignment of the homologues, mutagenesis analysis, and comparison of scorpion toxin family functions, we delineate some differences significant for the toxin specificity.

Three-dimensional structure of toxin OSK1 from Orthochirus scrobiculosus scorpion venom.,Jaravine VA, Nolde DE, Reibarkh MJ, Korolkova YV, Kozlov SA, Pluzhnikov KA, Grishin EV, Arseniev AS Biochemistry. 1997 Feb 11;36(6):1223-32. PMID:9063870^[2]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.

References

↑ Mouhat S, Visan V, Ananthakrishnan S, Wulff H, Andreotti N, Grissmer S, Darbon H, De Waard M, Sabatier JM. K+ channel types targeted by synthetic OSK1, a toxin from Orthochirus scrobiculosus scorpion venom. Biochem J. 2005 Jan 1;385(Pt 1):95-104. PMID:15588251 doi:http://dx.doi.org/BJ20041379
↑ Jaravine VA, Nolde DE, Reibarkh MJ, Korolkova YV, Kozlov SA, Pluzhnikov KA, Grishin EV, Arseniev AS. Three-dimensional structure of toxin OSK1 from Orthochirus scrobiculosus scorpion venom. Biochemistry. 1997 Feb 11;36(6):1223-32. PMID:9063870 doi:http://dx.doi.org/10.1021/bi9614390

1 Structural highlights
2 Function
3 Evolutionary Conservation
4 Publication Abstract from PubMed
5 See Also
6 References

Proteopedia Page Contributors and Editors (what is this?)

OCA

Retrieved from "http://52.214.119.220/wiki/index.php/1sco"

@@ Line 3: / Line 3: @@
 == Structural highlights ==
 <table><tr><td colspan='2'>[[1sco]] is a 1 chain structure with sequence from [http://en.wikipedia.org/wiki/Orthochirus_scrobiculosus Orthochirus scrobiculosus]. Full experimental information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1SCO OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1SCO FirstGlance]. <br>
-</td></tr><tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1sco FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1sco OCA], [http://www.rcsb.org/pdb/explore.do?structureId=1sco RCSB], [http://www.ebi.ac.uk/pdbsum/1sco PDBsum]</span></td></tr>
+</td></tr><tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1sco FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1sco OCA], [http://pdbe.org/1sco PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=1sco RCSB], [http://www.ebi.ac.uk/pdbsum/1sco PDBsum]</span></td></tr>
 </table>
+== Function ==
+[[http://www.uniprot.org/uniprot/KAX37_ORTSC KAX37_ORTSC]] Blocks voltage-gated potassium channels Kv1.1/KCNA1 (IC(50)=0.6nM), Kv1.2/KCNA2 (IC(50)=5.4nM), Kv1.3/KCNA3 (IC(50)=0.014nM) potently, and moderately block intermediate conductance calcium-activated potassium channels KCa3.1/KCNN4 (IC(50)=225nM). At high concentration (2 mM), is also active on Kv1.6/KCNA6 and Shaker IR.[REFERENCE:1]<ref>PMID:15588251</ref>
 == Evolutionary Conservation ==
 [[Image:Consurf_key_small.gif|200px|right]]
@@ Line 23: / Line 25: @@
 From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
 </div>
+<div class="pdbe-citations 1sco" style="background-color:#fffaf0;"></div>
 ==See Also==

1sco

From Proteopedia

Revision as of 21:32, 10 September 2015

SCORPION TOXIN (OSK1 TOXIN) WITH HIGH AFFINITY FOR SMALL CONDUCTANCE CA(2+)-ACTIVATED K+ CHANNEL IN NEUROBLASTOMA-X-GLUOMA NG 108-15 HYBRID CELLS, NMR, 30 STRUCTURES

Structural highlights

Function

Evolutionary Conservation

Publication Abstract from PubMed

See Also

References

Contents

Proteopedia Page Contributors and Editors (what is this?)

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