2I28 | pdb_00002i28

Solution Structure of alpha-Conotoxin BuIA

• PDB DOI: https://doi.org/10.2210/pdb2I28/pdb

• Classification: TOXIN
• Organism(s): Conus bullatus
• Mutation(s): No 
• Membrane Protein: Yes  OPM


• Deposited: 2006-08-16 Released: 2006-10-31 
• Deposition Author(s): Chi, S.-W., Kim, D.-H., Olivera, B.M., McIntosh, J.M., Han, K.-H.

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Experimental Data Snapshot

• Method: SOLUTION NMR
• Conformers Calculated: 50 
• Conformers Submitted: 20 
• Selection Criteria: structures with the lowest energy 

Literature

NMR structure determination of alpha-conotoxin BuIA, a novel neuronal nicotinic acetylcholine receptor antagonist with an unusual 4/4 disulfide scaffold

Chi, S.-W., Kim, D.-H., Olivera, B.M., McIntosh, J.M., Han, K.-H.

(2006) Biochem Biophys Res Commun 349: 1228-1234

• PubMed: 16979596 
• DOI: https://doi.org/10.1016/j.bbrc.2006.08.164
• Primary Citation Related Structures: 
  2I28


• PubMed Abstract: 
  

  We have determined a high-resolution three-dimensional structure of alpha-conotoxin BuIA, a 13-residue peptide toxin isolated from Conus bullatus. Despite its unusual 4/4 disulfide bond layout alpha-conotoxin BuIA exhibits strong antagonistic activity at alpha6/alpha3beta2beta3, alpha3beta2, and alpha3beta4 nAChR subtypes like some alpha4/7 conotoxins. alpha-Conotoxin BuIA lacks the C-terminal beta-turn present within the second disulfide loop of alpha4/7 conotoxins, having only a "pseudo omega-shaped" molecular topology. Nevertheless, it contains a functionally critical two-turn helix motif, a feature ubiquitously found in alpha4/7 conotoxins. Such an aspect seems mainly responsible for similarities in the receptor recognition profile of alpha-conotoxin BuIA to alpha4/7 conotoxins. Structural comparison of alpha-conotoxin BuIA with alpha4/7 conotoxins and alpha4/3 conotoxin ImI suggests that presence of the second helical turn portion of the two-turn helix motif in alpha4/7 and alpha4/4 conotoxins may be important for binding to the alpha3 and/or alpha6 subunit of nAChR.

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Organizational Affiliation: 
• Molecular Cancer Research Center, Division of Molecular Therapeutics, KRIBB, Daejeon 305-806, Republic of Korea.

Biological Assembly 1  

Global Symmetry: Asymmetric - C1 
Global Stoichiometry: Monomer - A1 

Biological assembly 1 assigned by authors.

Macromolecule Content 

• Total Structure Weight: 1.31 kDa 
• Atom Count: 88 
• Modeled Residue Count: 14 
• Deposited Residue Count: 14 
• Unique protein chains: 1

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
Alpha-conotoxin BuIA	A	14	N/A	Mutation(s): 0  Membrane Entity: Yes
UniProt
Find proteins for P69657 (Conus bullatus) Explore P69657  Go to UniProtKB:  P69657

Experimental Data & Validation

Experimental Data

• Method: SOLUTION NMR
• Conformers Calculated: 50 
• Conformers Submitted: 20 
• Selection Criteria: structures with the lowest energy 

Structure Validation

Entry History 

Deposition Data

• Released Date: 2006-10-31 
Deposition Author(s): Chi, S.-W., Kim, D.-H., Olivera, B.M., McIntosh, J.M., Han, K.-H.

Revision History  

• Version 1.0: 2006-10-31
  Type: Initial release
  
• Version 1.1: 2008-05-01
  Changes: Version format compliance
• Version 1.2: 2011-07-13
  Changes: Version format compliance
• Version 1.3: 2022-03-09
  Changes: Database references, Derived calculations
• Version 1.4: 2024-10-16
  Changes: Data collection, Structure summary