1MYP

X-RAY CRYSTAL STRUCTURE OF CANINE MYELOPEROXIDASE AT 3 ANGSTROMS RESOLUTION


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 3 Å

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

X-ray crystal structure of canine myeloperoxidase at 3 A resolution.

Zeng, J.Fenna, R.E.

(1992) J.Mol.Biol. 226: 185-207


  • PubMed Abstract: 
  • The three-dimensional structure of the enzyme myeloperoxidase has been determined by X-ray crystallography to 3 A resolution. Two heavy atom derivatives were used to phase an initial multiple isomorphous replacement map that was subsequently improved ...

    The three-dimensional structure of the enzyme myeloperoxidase has been determined by X-ray crystallography to 3 A resolution. Two heavy atom derivatives were used to phase an initial multiple isomorphous replacement map that was subsequently improved by solvent flattening and non-crystallographic symmetry averaging. Crystallographic refinement gave a final model with an R-factor of 0.257. The root-mean-square deviations from ideality for bond lengths and angles were 0.011 A and 3.8 degrees. Two, apparently identical, halves of the molecule are related by local dyad and covalently linked by a single disulfide bridge. Each half-molecule consists of two polypeptide chains of 108 and 466 amino acid residues, a heme prosthetic group, a bound calcium ion and at least three sites of asparagine-linked glycosylation. There are six additional intra-chain disulfide bonds, five in the large polypeptide and one in the small. A central core region that includes the heme binding site is composed of five alpha-helices. Regions of the larger polypeptide surrounding this core are organized into locally folded domains in which the secondary structure is predominantly alpha-helical with very little organized beta-sheet. A proximal ligand to the heme iron atom has been identified as histidine 336, which is in turn hydrogen-bonded to asparagine 421. On the distal side of the heme, histidine 95 and arginine 239 are likely to participate directly in the catalytic mechanism, in a manner analogous to the distal histidine and arginine of the non-homologous enzyme cytochrome c peroxidase. The site of the covalent linkage to the heme has been tentatively identified as glutamate 242, although the chemical nature of the link remains uncertain. The calcium binding site has been located in a loop comprising residues 168 to 174 together with aspartate 96. Myeloperoxidase is a member of a family of homologous mammalian peroxidases that includes thyroid peroxidase, eosinophil peroxidase and lactoperoxidase. The heme environment, defined by our model for myeloperoxidase, appears to be highly conserved in these four mammalian peroxidases. Furthermore, the conservation of all 12 cysteine residues involved in the six intra-chain disulfide bonds and the calcium binding loop suggests that the three-dimensional structures of members of this gene family are likely to be quite similar.


    Organizational Affiliation

    Department of Biochemistry and Molecular Biology, University of Miami Medical School, FL 33101.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
MYELOPEROXIDASE
A, B
108Homo sapiensMutation(s): 0 
Gene Names: MPO
EC: 1.11.2.2
Find proteins for P05164 (Homo sapiens)
Go to Gene View: MPO
Go to UniProtKB:  P05164
Entity ID: 2
MoleculeChainsSequence LengthOrganismDetails
MYELOPEROXIDASE
C, D
466Homo sapiensMutation(s): 0 
Gene Names: MPO
EC: 1.11.2.2
Find proteins for P05164 (Homo sapiens)
Go to Gene View: MPO
Go to UniProtKB:  P05164
Small Molecules
Ligands 3 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
CA
Query on CA

Download SDF File 
Download CCD File 
A, B
CALCIUM ION
Ca
BHPQYMZQTOCNFJ-UHFFFAOYSA-N
 Ligand Interaction
HEM
Query on HEM

Download SDF File 
Download CCD File 
A, B
PROTOPORPHYRIN IX CONTAINING FE
HEME
C34 H32 Fe N4 O4
KABFMIBPWCXCRK-RGGAHWMASA-L
 Ligand Interaction
NAG
Query on NAG

Download SDF File 
Download CCD File 
A, B
N-ACETYL-D-GLUCOSAMINE
C8 H15 N O6
OVRNDRQMDRJTHS-FMDGEEDCSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 3 Å
  • Space Group: P 41 21 2
Unit Cell:
Length (Å)Angle (°)
a = 133.000α = 90.00
b = 133.000β = 90.00
c = 203.600γ = 90.00
Software Package:
Software NamePurpose
TNTrefinement

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

  • Deposited Date: 1992-04-15 
  • Released Date: 1994-01-31 
  • Deposition Author(s): Fenna, R.E., Zeng, J.

Revision History 

  • Version 1.0: 1994-01-31
    Type: Initial release
  • Version 1.1: 2008-03-24
    Type: Version format compliance
  • Version 1.2: 2011-07-13
    Type: Non-polymer description, Version format compliance