1W7M

Crystal structure of human kynurenine aminotransferase I in complex with L-Phe


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.7 Å
  • R-Value Free: 0.232 
  • R-Value Work: 0.176 

wwPDB Validation 3D Report Full Report


This is version 1.1 of the entry. See complete history

Literature

Crystal Structure of Human Kynurenine Aminotransferase I

Rossi, F.Han, Q.Li, J.Li, J.Rizzi, M.

(2004) J.Biol.Chem. 279: 50214

  • DOI: 10.1074/jbc.M409291200
  • Primary Citation of Related Structures:  

  • PubMed Abstract: 
  • The kynurenine pathway has long been regarded as a valuable target for the treatment of several neurological disorders accompanied by unbalanced levels of metabolites along the catabolic cascade, kynurenic acid among them. The irreversible transamina ...

    The kynurenine pathway has long been regarded as a valuable target for the treatment of several neurological disorders accompanied by unbalanced levels of metabolites along the catabolic cascade, kynurenic acid among them. The irreversible transamination of kynurenine is the sole source of kynurenic acid, and it is catalyzed by different isoforms of the 5'-pyridoxal phosphate-dependent kynurenine aminotransferase (KAT). The KAT-I isozyme has also been reported to possess beta-lyase activity toward several sulfur- and selenium-conjugated molecules, leading to the proposal of a role of the enzyme in carcinogenesis associated with environmental pollutants. We solved the structure of human KAT-I in its 5'-pyridoxal phosphate and pyridoxamine phosphate forms and in complex with the competing substrate l-Phe. The enzyme active site revealed a striking crown of aromatic residues decorating the ligand binding pocket, which we propose as a major molecular determinant for substrate recognition. Ligand-induced conformational changes affecting Tyr(101) and the Trp(18)-bearing alpha-helix H1 appear to play a central role in catalysis. Our data reveal a key structural role of Glu(27), providing a molecular basis for the reported loss of enzymatic activity displayed by the equivalent Glu --> Gly mutation in KAT-I of spontaneously hypertensive rats.


    Organizational Affiliation

    Dipartimento di Scienze Chimiche, Alimentari, Farmaceutiche, Farmacologiche-Istituto Nazionale di Fisica della Materia, University of Piemonte Orientale "Amedeo Avogadro," Via Bovio 6, 28100 Novara, Italy.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
KYNURENINE--OXOGLUTARATE TRANSAMINASE I
A
422Homo sapiensMutation(s): 0 
Gene Names: KYAT1 (CCBL1)
EC: 2.6.1.7
Find proteins for Q16773 (Homo sapiens)
Go to Gene View: KYAT1
Go to UniProtKB:  Q16773
Small Molecules
Ligands 2 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
PHE
Query on PHE

Download SDF File 
Download CCD File 
A
PHENYLALANINE
C9 H11 N O2
COLNVLDHVKWLRT-QMMMGPOBSA-N
 Ligand Interaction
PLP
Query on PLP

Download SDF File 
Download CCD File 
A
PYRIDOXAL-5'-PHOSPHATE
VITAMIN B6 Phosphate
C8 H10 N O6 P
NGVDGCNFYWLIFO-UHFFFAOYSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.7 Å
  • R-Value Free: 0.232 
  • R-Value Work: 0.176 
  • Space Group: P 32 2 1
Unit Cell:
Length (Å)Angle (°)
a = 145.672α = 90.00
b = 145.672β = 90.00
c = 67.233γ = 120.00
Software Package:
Software NamePurpose
SCALAdata scaling
MOSFLMdata reduction
REFMACrefinement

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2004-09-08
    Type: Initial release
  • Version 1.1: 2015-09-16
    Type: Atomic model, Database references, Derived calculations, Non-polymer description, Other, Refinement description, Source and taxonomy, Structure summary, Version format compliance