1AQM

ALPHA-AMYLASE FROM ALTEROMONAS HALOPLANCTIS COMPLEXED WITH TRIS


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.85 Å
  • R-Value Free: 0.186 
  • R-Value Work: 0.157 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

Crystal structures of the psychrophilic alpha-amylase from Alteromonas haloplanctis in its native form and complexed with an inhibitor.

Aghajari, N.Feller, G.Gerday, C.Haser, R.

(1998) Protein Sci. 7: 564-572

  • DOI: 10.1002/pro.5560070304
  • Primary Citation of Related Structures:  1AQH

  • PubMed Abstract: 
  • Alteromonas haloplanctis is a bacterium that flourishes in Antarctic sea-water and it is considered as an extreme psychrophile. We have determined the crystal structures of the alpha-amylase (AHA) secreted by this bacterium, in its native state to 2. ...

    Alteromonas haloplanctis is a bacterium that flourishes in Antarctic sea-water and it is considered as an extreme psychrophile. We have determined the crystal structures of the alpha-amylase (AHA) secreted by this bacterium, in its native state to 2.0 angstroms resolution as well as in complex with Tris to 1.85 angstroms resolution. The structure of AHA, which is the first experimentally determined three-dimensional structure of a psychrophilic enzyme, resembles those of other known alpha-amylases of various origins with a surprisingly greatest similarity to mammalian alpha-amylases. AHA contains a chloride ion which activates the hydrolytic cleavage of substrate alpha-1,4-glycosidic bonds. The chloride binding site is situated approximately 5 angstroms from the active site which is characterized by a triad of acid residues (Asp 174, Glu 200, Asp 264). These are all involved in firm binding of the Tris moiety. A reaction mechanism for substrate hydrolysis is proposed on the basis of the Tris inhibitor binding and the chloride activation. A trio of residues (Ser 303, His 337, Glu 19) having a striking spatial resemblance with serine-protease like catalytic triads was found approximately 22 angstroms from the active site. We found that this triad is equally present in other chloride dependent alpha-amylases, and suggest that it could be responsible for autoproteolytic events observed in solution for this cold adapted alpha-amylase.


    Related Citations: 
    • Crystallization and Preliminary X-Ray Diffraction Studies of Alpha-Amylase from the Antarctic Psychrophile Alteromonas Haloplanctis A23
      Aghajari, N.,Feller, G.,Gerday, C.,Haser, R.
      (1996) Protein Sci. 5: 2128
    • Structures of the Psychrophilic Alteromonas Haloplanctis Alpha-Amylase Give Insights Into Cold Adaptation at a Molecular Level
      Aghajari, N.,Feller, G.,Gerday, C.,Haser, R.
      (1998) Structure 6: 1503
    • Structure and Molecular Model Refinement of Pig Pancreatic Alpha-Amylase at 2.1 A Resolution
      Qian, M.,Haser, R.,Payan, F.
      (1993) J.Mol.Biol. 231: 785


    Organizational Affiliation

    Laboratoire d'Architecture et Fonction des Macromolécules Biologiques, UPR9039, Institut de Biologie Structurale et Microbiologie, IFR1, CNRS, Marseille, France.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
ALPHA-AMYLASE
A
453Pseudoalteromonas haloplanktisGene Names: amy
EC: 3.2.1.1
Find proteins for P29957 (Pseudoalteromonas haloplanktis)
Go to UniProtKB:  P29957
Small Molecules
Ligands 3 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
CL
Query on CL

Download SDF File 
Download CCD File 
A
CHLORIDE ION
Cl
VEXZGXHMUGYJMC-UHFFFAOYSA-M
 Ligand Interaction
CA
Query on CA

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Download CCD File 
A
CALCIUM ION
Ca
BHPQYMZQTOCNFJ-UHFFFAOYSA-N
 Ligand Interaction
TRS
Query on TRS

Download SDF File 
Download CCD File 
A
2-AMINO-2-HYDROXYMETHYL-PROPANE-1,3-DIOL
TRIS BUFFER
C4 H12 N O3
LENZDBCJOHFCAS-UHFFFAOYSA-O
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.85 Å
  • R-Value Free: 0.186 
  • R-Value Work: 0.157 
  • Space Group: C 2 2 21
Unit Cell:
Length (Å)Angle (°)
a = 71.400α = 90.00
b = 138.900β = 90.00
c = 115.700γ = 90.00
Software Package:
Software NamePurpose
AGROVATAdata reduction
AMoREphasing
AGROVATAdata scaling
DENZOdata reduction
X-PLORrefinement

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 1999-03-02
    Type: Initial release
  • Version 1.1: 2008-03-24
    Type: Version format compliance
  • Version 1.2: 2011-07-13
    Type: Version format compliance