1ctx
From Proteopedia
(New page: 200px<br /><applet load="1ctx" size="450" color="white" frame="true" align="right" spinBox="true" caption="1ctx, resolution 2.8Å" /> '''THREE-DIMENSIONAL STR...) |
|||
| Line 1: | Line 1: | ||
| - | [[Image:1ctx.gif|left|200px]]<br /><applet load="1ctx" size=" | + | [[Image:1ctx.gif|left|200px]]<br /><applet load="1ctx" size="350" color="white" frame="true" align="right" spinBox="true" |
caption="1ctx, resolution 2.8Å" /> | caption="1ctx, resolution 2.8Å" /> | ||
'''THREE-DIMENSIONAL STRUCTURE OF THE-LONG-NEUROTOXIN FROM COBRA VENOM'''<br /> | '''THREE-DIMENSIONAL STRUCTURE OF THE-LONG-NEUROTOXIN FROM COBRA VENOM'''<br /> | ||
==Overview== | ==Overview== | ||
| - | The three-dimensional structure of alpha-cobra-toxin, the "long" | + | The three-dimensional structure of alpha-cobra-toxin, the "long" neurotoxin from the venom of Naja naja siamensis, has been determined at 2.8-A resolution. Crystals grown as hexagonal needles have space group P6522 with unit cell parameters a = b = 74.59 A, c = 42.89 A; one molecule per asymmetric unit. Phases were determined with a single isomorphous derivative with HgI2 by using the anomalous scattering of the single-site HgI2 molecule to resolve the phase ambiguity. The polypeptide chain folds into three major loops and one tail emerging from a globular head. The protruding long central loop (residues 21-40) is flanked on either side by two shorter loops (residues 4-13 and 44-55); the tail piece (residues 63-71) hangs behind this loop. The molecular conformation is determined by four disulfides in the head and one at the tip of the long loop, by a triple-stranded beta-pleated sheet involving this loop, and by hydrophobic interactions stabilizing the other two loops. The structure of alpha-cobratoxin is compared to that described for the "short" erabutoxin b which shows similar arrangement of structurally and functionally invariant groups. |
==About this Structure== | ==About this Structure== | ||
| - | 1CTX is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Naja_siamensis Naja siamensis]. Full crystallographic information is available from [http:// | + | 1CTX is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Naja_siamensis Naja siamensis]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1CTX OCA]. |
==Reference== | ==Reference== | ||
| Line 14: | Line 14: | ||
[[Category: Single protein]] | [[Category: Single protein]] | ||
[[Category: Saenger, W.]] | [[Category: Saenger, W.]] | ||
| - | [[Category: Walkinshaw, M | + | [[Category: Walkinshaw, M D.]] |
[[Category: toxin]] | [[Category: toxin]] | ||
| - | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 12:09:38 2008'' |
Revision as of 10:09, 21 February 2008
|
THREE-DIMENSIONAL STRUCTURE OF THE-LONG-NEUROTOXIN FROM COBRA VENOM
Overview
The three-dimensional structure of alpha-cobra-toxin, the "long" neurotoxin from the venom of Naja naja siamensis, has been determined at 2.8-A resolution. Crystals grown as hexagonal needles have space group P6522 with unit cell parameters a = b = 74.59 A, c = 42.89 A; one molecule per asymmetric unit. Phases were determined with a single isomorphous derivative with HgI2 by using the anomalous scattering of the single-site HgI2 molecule to resolve the phase ambiguity. The polypeptide chain folds into three major loops and one tail emerging from a globular head. The protruding long central loop (residues 21-40) is flanked on either side by two shorter loops (residues 4-13 and 44-55); the tail piece (residues 63-71) hangs behind this loop. The molecular conformation is determined by four disulfides in the head and one at the tip of the long loop, by a triple-stranded beta-pleated sheet involving this loop, and by hydrophobic interactions stabilizing the other two loops. The structure of alpha-cobratoxin is compared to that described for the "short" erabutoxin b which shows similar arrangement of structurally and functionally invariant groups.
About this Structure
1CTX is a Single protein structure of sequence from Naja siamensis. Full crystallographic information is available from OCA.
Reference
Three-dimensional structure of the "long" neurotoxin from cobra venom., Walkinshaw MD, Saenger W, Maelicke A, Proc Natl Acad Sci U S A. 1980 May;77(5):2400-4. PMID:6930640
Page seeded by OCA on Thu Feb 21 12:09:38 2008
