1idh
THE NMR SOLUTION STRUCTURE OF THE COMPLEX FORMED BETWEEN ALPHA-BUNGAROTOXIN AND AN 18MER COGNATE PEPTIDE
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OverviewOverview
The region encompassing residues 181-98 on the alpha1 subunit of the, muscle-type nicotinic acetylcholine receptor forms a major determinant for, the binding of alpha-neurotoxins. We have prepared an (15)N-enriched, 18-amino acid peptide corresponding to the sequence in this region to, facilitate structural elucidation by multidimensional NMR. Our aim was to, determine the structural basis for the high affinity, stoichiometric, complex formed between this cognate peptide and alpha-bungarotoxin, a long, alpha-neurotoxin. Resonances in the complex were assigned through, heteronuclear and homonuclear NMR experiments, and the resulting, interproton distance constraints were used to generate ensemble structures, of the complex. Thr(8), Pro(10), Lys(38), Val(39), Val(40), and Pro(69) in, alpha-bungarotoxin and Tyr(189), Tyr(190), Thr(191), Cys(192), Asp(195), and Thr(196) in the peptide participate in major intermolecular contacts., A comparison of the free and bound alpha-bungarotoxin structures reveals, significant conformational rearrangements in flexible regions of, alpha-bungarotoxin, mainly loops I, II, and the C-terminal tail., Furthermore, several of the calculated structures suggest that cation-pi, interactions may be involved in binding. The root mean square deviation of, the polypeptide backbone in the complex is 2.07 A. This structure, provides, to date, the highest resolution description of the contacts, between a prototypic alpha-neurotoxin and its cognate recognition, sequence.
About this StructureAbout this Structure
1IDH is a Protein complex structure of sequences from Bungarus multicinctus and Torpedo californica. Full crystallographic information is available from OCA.
ReferenceReference
The solution structure of the complex formed between alpha-bungarotoxin and an 18-mer cognate peptide derived from the alpha 1 subunit of the nicotinic acetylcholine receptor from Torpedo californica., Zeng H, Moise L, Grant MA, Hawrot E, J Biol Chem. 2001 Jun 22;276(25):22930-40. Epub 2001 Apr 18. PMID:11312275
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