7D37

Solution structure of Acm2-precursor peptide of Heat-stable enterotoxin produced by Enterotoxigenic Escherichia coli


Experimental Data Snapshot

  • Method: SOLUTION NMR
  • Conformers Calculated: 1000 
  • Conformers Submitted: 10 
  • Selection Criteria: structures with the lowest energy 

wwPDB Validation   3D Report Full Report


This is version 1.0 of the entry. See complete history


Literature

Topological Regulation of the Bioactive Conformation of a Disulfide-Rich Peptide, Heat-Stable Enterotoxin.

Shimamoto, S.Fukutsuji, M.Osumi, T.Goto, M.Toyoda, H.Hidaka, Y.

(2020) Molecules 25

  • DOI: https://doi.org/10.3390/molecules25204798
  • Primary Citation of Related Structures:  
    7CSS, 7D37

  • PubMed Abstract: 

    Heat-stable enterotoxin (ST a ) produced by enterotoxigenic E. coli causes acute diarrhea and also can be used as a specific probe for colorectal cancer cells. ST a contains three intra-molecular disulfide bonds (C1-C4, C2-C5, and C3-C6 connectivity). The chemical synthesis of ST a provided not only the native type of ST a but also a topological isomer that had the native disulfide pairings. Interestingly, the activity of the topological isomer was approximately 1/10-1/2 that of the native ST a . To further investigate the bioactive conformation of this molecule and the regulation of disulfide-coupled folding during its chemical syntheses, we examined the folding mechanism of ST a that occurs during its chemical synthesis. The folding intermediate of ST a with two disulfide bonds (C1-C4 and C3-C6) and two Cys(Acm) residues, the precursor peptide, was treated with iodine to produce a third disulfide bond under several conditions. The topological isomer was predominantly produced under all conditions tested, along with trace amounts of the native type of ST a . In addition, NMR measurements indicated that the topological isomer has a left-handed spiral structure similar to that of the precursor peptide, while the native type of ST a had a right-handed spiral structure. These results indicate that the order of the regioselective formation of disulfide bonds is important for the regulation of the final conformation of disulfide-rich peptides in chemical synthesis.


  • Organizational Affiliation

    Faculty of Science and Engineering, Kindai University, 3-4-1 Kowakae, Higashi-Osaka, Osaka 577-8502, Japan.


Macromolecules

Find similar proteins by:  Sequence   |   3D Structure  

Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
CYS-CY1-GLU-LEU-CYS-CYS-ASN-PRO-ALA-CY1-THR-GLY-CYS13Escherichia coliMutation(s): 0 
UniProt
Find proteins for P07965 (Escherichia coli)
Explore P07965 
Go to UniProtKB:  P07965
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupP07965
Sequence Annotations
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  • Reference Sequence
Small Molecules
Modified Residues  1 Unique
IDChains TypeFormula2D DiagramParent
CY1
Query on CY1
A
L-PEPTIDE LINKINGC6 H12 N2 O3 SCYS
Experimental Data & Validation

Experimental Data

  • Method: SOLUTION NMR
  • Conformers Calculated: 1000 
  • Conformers Submitted: 10 
  • Selection Criteria: structures with the lowest energy 

Structure Validation

View Full Validation Report



Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 2020-12-16
    Type: Initial release