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1lqi

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Revision as of 08:14, 23 February 2022

INSECTICIDAL ALPHA SCORPION TOXIN ISOLATED FROM THE VENOM OF SCORPION LEIURUS QUINQUESTRIATUS HEBRAEUS, NMR, 29 STRUCTURES

Structural highlights

1lqi is a 1 chain structure with sequence from Deathstalker scorpion. Full experimental information is available from OCA. For a guided tour on the structure components use FirstGlance.
Related:	1lqh
Gene:	POTENTIAL (Deathstalker scorpion)
Resources:	FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT

Function

[SCXA_LEIQH] Alpha toxins bind voltage-independently at site-3 of sodium channels (Nav) and inhibit the inactivation of the activated channels, thereby blocking neuronal transmission. The dissociation is voltage-dependent. This toxin is active on insects. It is also highly toxic to crustaceans and has a measurable but low toxicity to mice.

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

The solution structure of a recombinant active alpha-neurotoxin from Leiurus quinquestriatus hebraeus, Lqh(alpha)IT, was determined by proton two-dimensional nuclear magnetic resonance spectroscopy (2D NMR). This toxin is the most insecticidal among scorpion alpha-neurotoxins and, therefore, serves as a model for clarifying the structural basis for their biological activity and selective toxicity. A set of 29 structures was generated without constraint violations exceeding 0.4 A. These structures had root mean square deviations of 0.49 and 1.00 A with respect to the average structure for backbone atoms and all heavy atoms, respectively. Similarly to other scorpion toxins, the structure of Lqh(alpha)IT consists of an alpha-helix, a three-strand antiparallel beta-sheet, three type I tight turns, a five-residue turn, and a hydrophobic patch that includes tyrosine and tryptophan rings in a "herringbone" arrangement. Positive phi angles were found for Ala50 and Asn11, suggesting their proximity to functionally important regions of the molecule. The sample exhibited conformational heterogeneity over a wide range of experimental conditions, and two conformations were observed for the majority of protein residues. The ratio between these conformations was temperature-dependent, and the rate of their interconversions was estimated to be on the order of 1-5 s(-1) at 308 K. The conformation of the polypeptide backbone of Lqh(alpha)IT is very similar to that of the most active antimammalian scorpion alpha-toxin, AaHII, from Androctonus australis Hector (60% amino acid sequence homology). Yet, several important differences were observed at the 5-residue turn comprising residues Lys8-Cys12, the C-terminal segment, and the mutual disposition of these two regions. 2D NMR studies of the R64H mutant, which is 3 times more toxic than the unmodified Lqh(alpha)IT, demonstrated the importance of the spatial orientation of the last residue side chain for toxicity of Lqh(alpha)IT.

Solution structures of a highly insecticidal recombinant scorpion alpha-toxin and a mutant with increased activity.,Tugarinov V, Kustanovich I, Zilberberg N, Gurevitz M, Anglister J Biochemistry. 1997 Mar 4;36(9):2414-24. PMID:9054546^[1]

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

References

↑ Tugarinov V, Kustanovich I, Zilberberg N, Gurevitz M, Anglister J. Solution structures of a highly insecticidal recombinant scorpion alpha-toxin and a mutant with increased activity. Biochemistry. 1997 Mar 4;36(9):2414-24. PMID:9054546 doi:10.1021/bi961497l

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/1lqi"

@@ Line 3: / Line 3: @@
 <StructureSection load='1lqi' size='340' side='right'caption='[[1lqi]], [[NMR_Ensembles_of_Models | 29 NMR models]]' scene=''>
 == Structural highlights ==
-<table><tr><td colspan='2'>[[1lqi]] is a 1 chain structure with sequence from [http://en.wikipedia.org/wiki/Leiqh Leiqh]. Full experimental information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1LQI OCA]. For a <b>guided tour on the structure components</b> use [http://proteopedia.org/fgij/fg.htm?mol=1LQI FirstGlance]. <br>
+<table><tr><td colspan='2'>[[1lqi]] is a 1 chain structure with sequence from [https://en.wikipedia.org/wiki/Deathstalker_scorpion Deathstalker scorpion]. Full experimental information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1LQI OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=1LQI FirstGlance]. <br>
 </td></tr><tr id='related'><td class="sblockLbl"><b>[[Related_structure|Related:]]</b></td><td class="sblockDat"><div style='overflow: auto; max-height: 3em;'>[[1lqh|1lqh]]</div></td></tr>
-<tr id='gene'><td class="sblockLbl"><b>[[Gene|Gene:]]</b></td><td class="sblockDat">POTENTIAL ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=6884 LEIQH])</td></tr>
+<tr id='gene'><td class="sblockLbl"><b>[[Gene|Gene:]]</b></td><td class="sblockDat">POTENTIAL ([https://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=6884 Deathstalker scorpion])</td></tr>
-<tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[http://proteopedia.org/fgij/fg.htm?mol=1lqi FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1lqi OCA], [http://pdbe.org/1lqi PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=1lqi RCSB], [http://www.ebi.ac.uk/pdbsum/1lqi PDBsum], [http://prosat.h-its.org/prosat/prosatexe?pdbcode=1lqi ProSAT]</span></td></tr>
+<tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[https://proteopedia.org/fgij/fg.htm?mol=1lqi FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1lqi OCA], [https://pdbe.org/1lqi PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=1lqi RCSB], [https://www.ebi.ac.uk/pdbsum/1lqi PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=1lqi ProSAT]</span></td></tr>
 </table>
 == Function ==
-[[http://www.uniprot.org/uniprot/SCXA_LEIQH SCXA_LEIQH]] Alpha toxins bind voltage-independently at site-3 of sodium channels (Nav) and inhibit the inactivation of the activated channels, thereby blocking neuronal transmission. The dissociation is voltage-dependent. This toxin is active on insects. It is also highly toxic to crustaceans and has a measurable but low toxicity to mice.
+[[https://www.uniprot.org/uniprot/SCXA_LEIQH SCXA_LEIQH]] Alpha toxins bind voltage-independently at site-3 of sodium channels (Nav) and inhibit the inactivation of the activated channels, thereby blocking neuronal transmission. The dissociation is voltage-dependent. This toxin is active on insects. It is also highly toxic to crustaceans and has a measurable but low toxicity to mice.
 == Evolutionary Conservation ==
 [[Image:Consurf_key_small.gif|200px|right]]
@@ Line 37: / Line 37: @@
 __TOC__
 </StructureSection>
+[[Category: Deathstalker scorpion]]
 [[Category: Large Structures]]
-[[Category: Leiqh]]
 [[Category: Anglister, J]]
 [[Category: Gurevitz, M]]

1lqi

From Proteopedia

Revision as of 08:14, 23 February 2022

INSECTICIDAL ALPHA SCORPION TOXIN ISOLATED FROM THE VENOM OF SCORPION LEIURUS QUINQUESTRIATUS HEBRAEUS, NMR, 29 STRUCTURES

Structural highlights

Function

Evolutionary Conservation

Publication Abstract from PubMed

See Also

References

Contents

Proteopedia Page Contributors and Editors (what is this?)

Views

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