1ETL

STRUCTURAL CHARACTERISTICS FOR BIOLOGICAL ACTIVITY OF HEAT-STABLE ENTEROTOXIN PRODUCED BY ENTEROTOXIGENIC ESCHERICHIA COLI: X-RAY CRYSTALLOGRAPHY OF WEAKLY TOXIC AND NONTOXIC ANALOGS


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 0.89 Å
  • R-Value Work: 0.073 

wwPDB Validation 3D Report Full Report


This is version 1.4 of the entry. See complete history

Literature

Structural characteristics for biological activity of heat-stable enterotoxin produced by enterotoxigenic Escherichia coli: X-ray crystallography of weakly toxic and nontoxic analogs.

Sato, T.Ozaki, H.Hata, Y.Kitagawa, Y.Katsube, Y.Shimonishi, Y.

(1994) Biochemistry 33: 8641-8650

  • Primary Citation of Related Structures:  1ETM

  • PubMed Abstract: 
  • Heat-stable enterotoxin (ST) produced by a pathogenic strain of Escherichia coli exerts its function by binding to a membrane-bound guanylyl cyclase on intestinal epithelial cell membranes, which in turn catalyzes the production of cyclic GMP as a se ...

    Heat-stable enterotoxin (ST) produced by a pathogenic strain of Escherichia coli exerts its function by binding to a membrane-bound guanylyl cyclase on intestinal epithelial cell membranes, which in turn catalyzes the production of cyclic GMP as a second messenger in the cells. To elucidate the structural requirements for the biological activities of ST, we synthesized [Mpr5,Gly13]STp(5-17) and [Mpr5,Leu13]STp(5-17), which are weakly toxic and nontoxic analogs of STp, in which the toxic domain consists of the sequence from Cys at position 5 to Cys at position 17. In these analogs, Cys at position 5 is replaced by Mpr (beta-mercaptopropionic acid) and Ala at position 13 by Gly and Leu, respectively. We examined these analogs by X-ray diffraction analysis using direct methods and refined the structures to crystallographic R factors of 7.3% and 6.6% using 5492 and 5122 data, respectively, observed > 3 sigma (Fo) with a resolution of 0.89 A. These peptides have a right-handed spiral structure consisting of three structural segments: an N-terminal 3(10) helix, a central type I beta-turn, and a C-terminal type II beta-turn. These structures show minor differences from that of [Mpr5]STp(5-17), the fully toxic analog of heat-stable enterotoxin [Ozaki et al. (1991) J. Biol. Chem. 266, 5934-5941], suggesting that the decrease and loss of the biological activities of [Mpr5,Gly13]STp(5-17) and [Mpr5,Leu13]STp(5-17), respectively, are not caused by structural changes but are associated with the direct interaction of Ala13 with the receptor protein. Careful comparison of these structures in crystalline states revealed that ST has the following structural characteristics: (i) inherent flexibility at the junctions of the three segments and in the central segment, which includes the putative receptor-binding residues, Ala13, (ii) a specific hydrophobic character around the central segment, and (iii) an unexpected C-terminal folding similar to those of functionally unrelated peptides that are known to be ionophores.


    Related Citations: 
    • Molecular Structure of the Toxic Domain of Heat-Stable Enterotoxin Produced by a Pathogenic Strain of Escherichia Coli
      Ozaki, H.,Sato, T.,Kubota, H.,Hata, Y.,Katsube, Y.,Shimonishi, Y.
      (1991) J.Biol.Chem. 266: 5934
    • Structure-Activity Relationship of Escherichia Coli Heat-Stable Enterotoxin: Role of Ala Residue at Position 14 in Toxin-Receptor Interaction
      Yamasaki, S.,Sato, T.,Hidaka, Y.,Ozaki, H.,Ito, H.,Hirayama, T.,Takeda, Y.,Sugimura, T.,Tai, A.,Shimonishi, Y.
      (1990) Bull.Chem.Soc.Jpn. 63: 2063
    • Semi-Preparative Purification and Crystallization of Synthetic Analogs of Heat-Stable Enterotoxin of Enterotoxigenic Escherichia Coli
      Sato, T.,Ito, H.,Takeda, Y.,Shimonishi, Y.
      (1992) Bull.Chem.Soc.Jpn. 65: 938
    • Essential Structure for Full Enterotoxigenic Activity of Heat-Stable Enterotoxin Produced by Enterotoxigenic Escherichia Coli
      Yoshimura, S.,Ikemura, H.,Watanabe, H.,Aimoto, S.,Shimonishi, Y.,Hara, S.,Takeda, T.,Miwatani, T.,Takeda, Y.
      (1985) FEBS Lett. 181: 138


    Organizational Affiliation

    Institute for Protein Research, Osaka University, Japan.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
5-BETA-MERCAPTOPROPIONATE HEAT-STABLE ENTEROTOXIN
A
13Escherichia coliGene Names: sta1
Find proteins for P01559 (Escherichia coli)
Go to UniProtKB:  P01559
Small Molecules
Modified Residues  1 Unique
IDChainsTypeFormula2D DiagramParent
MPR
Query on MPR
A
NON-POLYMERC3 H6 O S

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Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 0.89 Å
  • R-Value Work: 0.073 
  • Space Group: P 1 21 1
Unit Cell:
Length (Å)Angle (°)
a = 21.928α = 90.00
b = 10.219β = 111.71
c = 17.891γ = 90.00
Software Package:
Software NamePurpose
FMLS/VPrefinement

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 1996-01-29
    Type: Initial release
  • Version 1.1: 2008-03-03
    Type: Version format compliance
  • Version 1.2: 2011-07-13
    Type: Version format compliance
  • Version 1.3: 2013-06-19
    Type: Other
  • Version 1.4: 2017-11-29
    Type: Derived calculations, Other