1IDI

THE NMR SOLUTION STRUCTURE OF ALPHA-BUNGAROTOXIN

Summary for 1IDI

• Entry DOI: 10.2210/pdb1idi/pdb
• Related: 1IDG 1IDH 1IDL
• Descriptor: ALPHA-BUNGAROTOXIN (1 entity in total)
• Functional Keywords: alpha-bungarotoxin, alpha-neurotoxin, nmr solution structure, toxin
• Biological source: Bungarus multicinctus (many-banded krait)
• Cellular location: Secreted: P60615
• Total number of polymer chains: 1
• Total formula weight: 8005.28

Authors

Zeng, H.,Moise, L.,Grant, M.A.,Hawrot, E. (deposition date: 2001-04-04, release date: 2001-04-25, Last modification date: 2024-10-30)

Primary citation

Zeng, H.,Moise, L.,Grant, M.A.,Hawrot, E.
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.
J.Biol.Chem., 276:22930-22940, 2001

PubMed Abstract: 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.

PubMed: 11312275
DOI: 10.1074/jbc.M102300200

Experimental method

SOLUTION NMR