5HHY

Structure of human Alanine:Glyoxylate Aminotransferase major allele (AGT-Ma) showing X-Ray induced reduction of PLP internal aldimine to 4'-deoxy-piridoxine-phosphate (PLR)


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.70 Å
  • R-Value Free: 0.205 
  • R-Value Work: 0.164 
  • R-Value Observed: 0.166 

wwPDB Validation   3D Report Full Report


Ligand Structure Quality Assessment 


This is version 1.1 of the entry. See complete history


Literature

Radiation damage at the active site of human alanine:glyoxylate aminotransferase reveals that the cofactor position is finely tuned during catalysis.

Giardina, G.Paiardini, A.Montioli, R.Cellini, B.Voltattorni, C.B.Cutruzzola, F.

(2017) Sci Rep 7: 11704-11704

  • DOI: 10.1038/s41598-017-11948-w
  • Primary Citation of Related Structures:  
    5OFY, 5OG0, 5HHY, 5LUC, 5F9S

  • PubMed Abstract: 
  • The alanine:glyoxylate aminotransferase (AGT), a hepatocyte-specific pyridoxal-5'-phosphate (PLP) dependent enzyme, transaminates L-alanine and glyoxylate to glycine and pyruvate, thus detoxifying glyoxylate and preventing pathological oxalate precipitation in tissues ...

    The alanine:glyoxylate aminotransferase (AGT), a hepatocyte-specific pyridoxal-5'-phosphate (PLP) dependent enzyme, transaminates L-alanine and glyoxylate to glycine and pyruvate, thus detoxifying glyoxylate and preventing pathological oxalate precipitation in tissues. In the widely accepted catalytic mechanism of the aminotransferase family, the lysine binding to PLP acts as a catalyst in the stepwise 1,3-proton transfer, interconverting the external aldimine to ketimine. This step requires protonation by a conserved aspartate of the pyridine nitrogen of PLP to enhance its ability to stabilize the carbanionic intermediate. The aspartate residue is also responsible for a significant geometrical distortion of the internal aldimine, crucial for catalysis. We present the structure of human AGT in which complete X-ray photoreduction of the Schiff base has occurred. This result, together with two crystal structures of the conserved aspartate pathogenic variant (D183N) and the molecular modeling of the transaldimination step, led us to propose that an interplay of opposite forces, which we named spring mechanism, finely tunes PLP geometry during catalysis and is essential to move the external aldimine in the correct position in order for the 1,3-proton transfer to occur.


    Organizational Affiliation

    Istituto Pasteur of Italy - Fondazione Cenci Bolognetti, Rome, Italy.



Macromolecules
Find similar proteins by:  (by identity cutoff)  |  Structure
Entity ID: 1
MoleculeChainsSequence LengthOrganismDetailsImage
Serine--pyruvate aminotransferaseA, B386Homo sapiensMutation(s): 0 
Gene Names: AGXTAGT1SPAT
EC: 2.6.1.51 (PDB Primary Data), 2.6.1.44 (PDB Primary Data)
UniProt & NIH Common Fund Data Resources
Find proteins for P21549 (Homo sapiens)
Explore P21549 
Go to UniProtKB:  P21549
PHAROS:  P21549
Protein Feature View
Expand
  • Reference Sequence
Small Molecules
Ligands 1 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
PLR (Subject of Investigation/LOI)
Query on PLR

Download Ideal Coordinates CCD File 
C [auth A], D [auth B](5-HYDROXY-4,6-DIMETHYLPYRIDIN-3-YL)METHYL DIHYDROGEN PHOSPHATE
C8 H12 N O5 P
RBCOYOYDYNXAFA-UHFFFAOYSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.70 Å
  • R-Value Free: 0.205 
  • R-Value Work: 0.164 
  • R-Value Observed: 0.166 
  • Space Group: P 21 21 21
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 54.479α = 90
b = 101.88β = 90
c = 131.338γ = 90
Software Package:
Software NamePurpose
Aimlessdata scaling
MOLREPphasing
PHENIXrefinement
PDB_EXTRACTdata extraction
XDSdata reduction

Structure Validation

View Full Validation Report



Ligand Structure Quality Assessment  



Entry History & Funding Information

Deposition Data


Funding OrganizationLocationGrant Number
Oxalosis and Hyperoxaluria FoundationUnited KingdomOHF2011
European Community's Seventh Framework Programme FP7/2007-2013BioStruct-X project 6943 grant agreement n.283570

Revision History  (Full details and data files)

  • Version 1.0: 2017-01-25
    Type: Initial release
  • Version 1.1: 2017-09-27
    Changes: Advisory, Database references