1ctx
From Proteopedia
OCA (Talk | contribs)
(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...)
Next diff →
Revision as of 10:38, 20 November 2007
|
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 Tue Nov 20 12:45:27 2007
