1Q2K | pdb_00001q2k

Solution structure of BmBKTx1 a new potassium channel blocker from the Chinese Scorpion Buthus martensi Karsch

• PDB DOI: https://doi.org/10.2210/pdb1Q2K/pdb

• Classification: TOXIN
• Organism(s): Olivierus martensii
• Mutation(s): No 


• Deposited: 2003-07-25 Released: 2003-09-09 
• Deposition Author(s): Cai, Z., Xu, C., Xu, Y., Lu, W., Chi, C.W., Shi, Y., Wu, J.

---

Experimental Data Snapshot

• Method: SOLUTION NMR
• Conformers Calculated: 100 
• Conformers Submitted: 21 
• Selection Criteria: structures with the lowest energy 

Literature

Solution Structure of BmBKTx1, a New BK(Ca)(1) Channel Blocker from the Chinese Scorpion Buthus martensi Karsch(,).

Cai, Z., Xu, C., Xu, Y., Lu, W., Chi, C.W., Shi, Y., Wu, J.

(2004) Biochemistry 43: 3764-3771

• PubMed: 15049683 
• DOI: https://doi.org/10.1021/bi035412+
• Primary Citation Related Structures: 
  1Q2K


• PubMed Abstract: 
  

  BmBKTx1 is a 31-amino acid peptide identified from the venom of the Chinese scorpion Buthus martensi Karsch, blocking high-conductance calcium-activated potassium channels. Sequence homology analysis indicates that BmBKTx1 is a new subfamily of short-chain alpha-KTx toxins of the potassium channel, which we term alpha-KTx19. Synthetic BmBKTx1 was prepared by using solid-phase peptide synthesis. Two-dimensional NMR spectroscopy techniques were used to determine the solution structure of BmBKTx1. The results show that the BmBKTx1 forms a typical cysteine-stabilized alpha/beta scaffold adopted by most short-chain scorpion toxins. The structure of BmBKTx1 consists of a two-stranded antiparallel beta-sheet (residues 20-29) and an alpha-helix (residues 5-15). The three-dimensional structure of BmBKTx1 was also compared with those of two function-related scorpion toxins, charybdotoxin (ChTx) and BmTx1, and their structural and functional implications are discussed.

---

Organizational Affiliation: 
• Laboratory of Structural Biology, School of Life Science, University of Science and Technology of China, Hefei, Anhui, PRC.

Biological Assembly 1  

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

Biological assembly 1 assigned by authors.

Macromolecule Content 

• Total Structure Weight: 3.35 kDa 
• Atom Count: 227 
• Modeled Residue Count: 31 
• Deposited Residue Count: 31 
• Unique protein chains: 1

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
Neurotoxin BmK37	A	31	N/A	Mutation(s): 0
UniProt
Find proteins for P83407 (Olivierus martensii) Explore P83407  Go to UniProtKB:  P83407

Experimental Data & Validation

Experimental Data

• Method: SOLUTION NMR
• Conformers Calculated: 100 
• Conformers Submitted: 21 
• Selection Criteria: structures with the lowest energy 

Structure Validation

Entry History 

Deposition Data

• Released Date: 2003-09-09 
Deposition Author(s): Cai, Z., Xu, C., Xu, Y., Lu, W., Chi, C.W., Shi, Y., Wu, J.

Revision History  

• Version 1.0: 2003-09-09
  Type: Initial release
  
• Version 1.1: 2008-04-29
  Changes: Version format compliance
• Version 1.2: 2011-07-13
  Changes: Version format compliance
• Version 1.3: 2022-03-02
  Changes: Data collection, Database references, Derived calculations
• Version 1.4: 2024-10-09
  Changes: Data collection, Structure summary