1pvz
From Proteopedia
(New page: 200px<br /><applet load="1pvz" size="450" color="white" frame="true" align="right" spinBox="true" caption="1pvz" /> '''Solution Structure of BmP07, A Novel Potassi...) |
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| - | [[Image:1pvz.gif|left|200px]]<br /><applet load="1pvz" size=" | + | [[Image:1pvz.gif|left|200px]]<br /><applet load="1pvz" size="350" color="white" frame="true" align="right" spinBox="true" |
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'''Solution Structure of BmP07, A Novel Potassium Channel Blocker from Scorpion Buthus martensi Karsch, 15 structures'''<br /> | '''Solution Structure of BmP07, A Novel Potassium Channel Blocker from Scorpion Buthus martensi Karsch, 15 structures'''<br /> | ||
==Overview== | ==Overview== | ||
| - | A natural K+ channel blocker, BmKK2 (a member of scorpion toxin subfamily | + | A natural K+ channel blocker, BmKK2 (a member of scorpion toxin subfamily alpha-KTx 14), which is composed of 31 amino acid residues and purified from the venom of the Chinese scorpion Buthus martensi Karsch, was characterized using whole-cell patch-clamp recording in rat hippocampal neurons. The three dimensional structure of BmKK2 was determined with two-dimensional NMR spectroscopy and molecular modelling techniques. In solution this toxin adopted a common alpha/beta-motif, but showed distinct local conformation in the loop between alpha-helix and beta-sheet in comparison with typical short-chain scorpion toxins (e.g., CTX and NTX). Also, the alpha helix is shorter and the beta-sheet element is smaller (each strand consisted only two residues). The unusual structural feature of BmKK2 was attributed to the shorter loop between the alpha-helix and beta-sheet and the presence of two consecutive Pro residues at position 21 and 22 in the loop. Moreover, two models of BmKK2/hKv1.3 channel and BmKK2/rSK2 channel complexes were simulated with docking calculations. The results demonstrated the existence of a alpha-mode binding between the toxin and the channels. The model of BmKK2/rSK2 channel complex exhibited favorable contacts both in electrostatic and hydrophobic, including a network of five hydrogen bonds and bigger interface containing seven pairs of inter-residue interactions. In contrast, the model of BmKK2/hKv1.3 channel complex, containing only three pairs of inter-residue interactions, exhibited poor contacts and smaller interface. The results well explained its lower activity towards Kv channel, and predicted that it may prefer a type of SK channel with a narrower entryway as its specific receptor. |
==About this Structure== | ==About this Structure== | ||
| - | 1PVZ is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Mesobuthus_martensii Mesobuthus martensii]. Full crystallographic information is available from [http:// | + | 1PVZ is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Mesobuthus_martensii Mesobuthus martensii]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1PVZ OCA]. |
==Reference== | ==Reference== | ||
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[[Category: alpha/beta scaffold]] | [[Category: alpha/beta scaffold]] | ||
| - | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 14:33:05 2008'' |
Revision as of 12:33, 21 February 2008
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Solution Structure of BmP07, A Novel Potassium Channel Blocker from Scorpion Buthus martensi Karsch, 15 structures
Overview
A natural K+ channel blocker, BmKK2 (a member of scorpion toxin subfamily alpha-KTx 14), which is composed of 31 amino acid residues and purified from the venom of the Chinese scorpion Buthus martensi Karsch, was characterized using whole-cell patch-clamp recording in rat hippocampal neurons. The three dimensional structure of BmKK2 was determined with two-dimensional NMR spectroscopy and molecular modelling techniques. In solution this toxin adopted a common alpha/beta-motif, but showed distinct local conformation in the loop between alpha-helix and beta-sheet in comparison with typical short-chain scorpion toxins (e.g., CTX and NTX). Also, the alpha helix is shorter and the beta-sheet element is smaller (each strand consisted only two residues). The unusual structural feature of BmKK2 was attributed to the shorter loop between the alpha-helix and beta-sheet and the presence of two consecutive Pro residues at position 21 and 22 in the loop. Moreover, two models of BmKK2/hKv1.3 channel and BmKK2/rSK2 channel complexes were simulated with docking calculations. The results demonstrated the existence of a alpha-mode binding between the toxin and the channels. The model of BmKK2/rSK2 channel complex exhibited favorable contacts both in electrostatic and hydrophobic, including a network of five hydrogen bonds and bigger interface containing seven pairs of inter-residue interactions. In contrast, the model of BmKK2/hKv1.3 channel complex, containing only three pairs of inter-residue interactions, exhibited poor contacts and smaller interface. The results well explained its lower activity towards Kv channel, and predicted that it may prefer a type of SK channel with a narrower entryway as its specific receptor.
About this Structure
1PVZ is a Single protein structure of sequence from Mesobuthus martensii. Full crystallographic information is available from OCA.
Reference
Solution structure of BmKK2, a new potassium channel blocker from the venom of chinese scorpion Buthus martensi Karsch., Zhang N, Li M, Chen X, Wang Y, Wu G, Hu G, Wu H, Proteins. 2004 Jun 1;55(4):835-45. PMID:15146482
Page seeded by OCA on Thu Feb 21 14:33:05 2008
Categories: Mesobuthus martensii | Single protein | Hu, G. | Li, M. | Ou, L. | Wang, Y. | Wu, H. | Zhang, N. | Zhang, Q. | Alpha/beta scaffold
