1EKF

CRYSTALLOGRAPHIC STRUCTURE OF HUMAN BRANCHED CHAIN AMINO ACID AMINOTRANSFERASE (MITOCHONDRIAL) COMPLEXED WITH PYRIDOXAL-5'-PHOSPHATE AT 1.95 ANGSTROMS (ORTHORHOMBIC FORM)


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.95 Å
  • R-Value Free: 0.260 
  • R-Value Work: 0.222 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

The structure of human mitochondrial branched-chain aminotransferase.

Yennawar, N.Dunbar, J.Conway, M.Hutson, S.Farber, G.

(2001) Acta Crystallogr.,Sect.D 57: 506-515

  • Primary Citation of Related Structures:  1EKP, 1EKV

  • PubMed Abstract: 
  • X-ray crystal structures of three forms of human mitochondrial branched-chain aminotransferase (BCAT) were solved by molecular-replacement methods, using Escherichia coli BCAT as the search model. The enzyme is a homodimer and the polypeptide chain o ...

    X-ray crystal structures of three forms of human mitochondrial branched-chain aminotransferase (BCAT) were solved by molecular-replacement methods, using Escherichia coli BCAT as the search model. The enzyme is a homodimer and the polypeptide chain of each monomer has two domains. The small domain is composed of residues 1--175 and the large domain is composed of residues 176--365. The active site is close to the dimer interface. The 4'-aldehyde of the PLP cofactor is covalently linked to the epsilon-amino group of the active-site lysine, Lys202, via a Schiff-base linkage in two of the structures. In the third structure, the enzyme is irreversibly inactivated by Tris. The overall fold of the dimer in human mitochondrial BCAT is similar to the structure of two bacterial enzymes, E. coli BCAT and D-amino acid aminotransferase (D-AAT). The residues lining the putative substrate-binding pocket of human BCAT and D-AAT are completely rearranged to allow catalysis with substrates of opposite stereochemistry. In the case of human mitochondrial branched-chain aminotransferase, a hydrogen-bond interaction between the guanidinium group of Arg143 in the first monomer with the side-chain hydroxyl of Tyr70 in the second monomer is important in the formation of the substrate-binding pocket.


    Related Citations: 
    • Cloning of the Rat and Human Mitochondrial Branched Chain Aminotransferases (BCATm)
      Bledsoe, R.K.,Dawson, P.A.,Hutson, S.M.
      (1997) BIOCHIM.BIOPHYS.ACTA 1339: 9


    Organizational Affiliation

    Department of Biochemistry and Molecular Biology, Penn State University, University Park, PA 16802, USA. nhy1@psu.edu




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
BRANCHED CHAIN AMINO ACID AMINOTRANSFERASE (MITOCHONDRIAL)
A, B
365Homo sapiensGene Names: BCAT2 (BCATM, BCT2, ECA40)
EC: 2.6.1.42
Find proteins for O15382 (Homo sapiens)
Go to Gene View: BCAT2
Go to UniProtKB:  O15382
Small Molecules
Ligands 1 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
PLP
Query on PLP

Download SDF File 
Download CCD File 
A, B
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: 1.95 Å
  • R-Value Free: 0.260 
  • R-Value Work: 0.222 
  • Space Group: P 21 21 21
Unit Cell:
Length (Å)Angle (°)
a = 69.385α = 90.00
b = 105.032β = 90.00
c = 107.016γ = 90.00
Software Package:
Software NamePurpose
DENZOdata reduction
CNSrefinement
SCALEPACKdata scaling
AMoREphasing

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2001-03-08
    Type: Initial release
  • Version 1.1: 2008-04-27
    Type: Version format compliance
  • Version 1.2: 2011-07-13
    Type: Non-polymer description, Version format compliance