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PDBsum entry 1bkt
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References listed in PDB file
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Key reference
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Title
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Solution structure of bmktx, A k+ blocker toxin from the chinese scorpion buthus martensi.
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Authors
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J.G.Renisio,
R.Romi-Lebrun,
E.Blanc,
O.Bornet,
T.Nakajima,
H.Darbon.
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Ref.
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Proteins, 2000,
38,
70-78.
[DOI no: ]
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PubMed id
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Note In the PDB file this reference is
annotated as "TO BE PUBLISHED".
The citation details given above were identified by an automated
search of PubMed on title and author
names, giving a
percentage match of
0%.
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Abstract
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BmKTX is a toxin recently purified from the venom of Buthus Martensi, which
belongs to the kaliotoxin family. We have determined its solution structure by
use of conventional two-dimensional NMR techniques followed by distance-geometry
and energy minimization. The calculated structure is composed of a short
alpha-helix (residues 14 to 20) connected by a tight turn to a two-stranded
antiparallel beta-sheet (sequences 25-27 and 32-34). The beta-turn connecting
these strands belongs to type I. The N-terminal segment (sequence 1 to 8) runs
parallel to the beta-sheet although it cannot be considered as a third strand.
Comparison of the conformation of BmKTX and toxins of the kaliotoxin family
clearly demonstrates that they are highly related. Therefore, analysis of the
residues belonging to the interacting surface of those toxins allows us to
propose a functional map of BmKTX slightly different from the one of KTX and
AgTX2, which may explain the variations in affinities of these toxins towards
the Kv1.3 channels.
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Figure 5.
Figure 5. The toxin functional maps. The structures on the
left, middle, and right correspond to KTX, BmKTX, and AgTX2
respectively. The residues crucial for toxins to interact with
the Kv1.3 channel are in red. Influential residues are in blue
and additional residues are in pink. Histidine H9, the residue
that determines the specificity of BmKTX interaction with the
Kv1.3 channel, is in green.
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Figure 6.
Figure 6. Docking of BmKTX on a model of Kv1.3. The channel
backbone is in yellow and its interacting side chains in orange.
BmKTX backbone is in gray and its interacting side chains are in
red for crucial residues, in blue for influential residues, and
in pink for additional residues. Highlighted histidine H9 is in
green.
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The above figures are
reprinted
by permission from John Wiley & Sons, Inc.:
Proteins
(2000,
38,
70-78)
copyright 2000.
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