2CFB

Glutamate-1-semialdehyde 2,1-Aminomutase from Thermosynechococcus elongatus


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.85 Å
  • R-Value Free: 0.220 
  • R-Value Work: 0.173 

wwPDB Validation 3D Report Full Report


This is version 1.1 of the entry. See complete history

Literature

Evolutionary Relationship between Initial Enzymes of Tetrapyrrole Biosynthesis

Schulze, J.O.Schubert, W.-D.Moser, J.Jahn, D.Heinz, D.W.

(2006) J.Mol.Biol. 358: 1212

  • DOI: 10.1016/j.jmb.2006.02.064

  • PubMed Abstract: 
  • Glutamate-1-semialdehyde 2,1-aminomutase (GSAM) is the second enzyme in the C(5) pathway of tetrapyrrole biosynthesis found in most bacteria, in archaea and in plants. It catalyzes the transamination of glutamate-1-semialdehyde to 5-aminolevulinic ac ...

    Glutamate-1-semialdehyde 2,1-aminomutase (GSAM) is the second enzyme in the C(5) pathway of tetrapyrrole biosynthesis found in most bacteria, in archaea and in plants. It catalyzes the transamination of glutamate-1-semialdehyde to 5-aminolevulinic acid (ALA) in a pyridoxal 5'-phosphate (PLP)-dependent manner. We present the crystal structure of GSAM from the thermophilic cyanobacterium Thermosynechococcus elongatus (GSAM(Tel)) in its PLP-bound form at 2.85A resolution. GSAM(Tel) is a symmetric homodimer, whereas GSAM from Synechococcus (GSAM(Syn)) has been described as asymmetric. The symmetry of GSAM(Tel) thus challenges the previously proposed negative cooperativity between monomers of this enzyme. Furthermore, GSAM(Tel) reveals an extensive flexible region at the interface of the proposed complex of GSAM with glutamyl-tRNA reductase (GluTR), the preceding enzyme in tetrapyrrole biosynthesis. Compared to GSAM(Syn), the monomers of GSAM(Tel) are rotated away from each other along the dimerization interface by 10 degrees . The associated flexibility of GSAM may be essential for complex formation with GluTR to occur. Unexpectedly, we find that GSAM is structurally related to 5-aminolevulinate synthase (ALAS), the ALA-producing enzyme in the Shemin pathway of alpha-proteobacteria and non-plant eukaryotes. This structural relationship applies also to the corresponding subfamilies of PLP-dependent enzymes. We thus propose that the CoA-subfamily (including ALAS) and the aminotransferase subfamily II (including GSAM) are evolutionarily closely related and that ALAS may thus have evolved from GSAM.


    Organizational Affiliation

    Division of Structural Biology, German Research Centre for Biotechnology (GBF), Mascheroder Weg 1, D-38124 Braunschweig, Germany.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
GLUTAMATE-1-SEMIALDEHYDE 2,1-AMINOMUTASE
A
411Thermosynechococcus elongatus (strain BP-1)Mutation(s): 0 
Gene Names: hemL
EC: 5.4.3.8
Find proteins for Q8DLK8 (Thermosynechococcus elongatus (strain BP-1))
Go to UniProtKB:  Q8DLK8
Small Molecules
Ligands 1 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
PLR
Query on PLR

Download SDF File 
Download CCD File 
A
(5-HYDROXY-4,6-DIMETHYLPYRIDIN-3-YL)METHYL DIHYDROGEN PHOSPHATE
4'-DEOXYPYRIDOXINE PHOSPHATE
C8 H12 N O5 P
RBCOYOYDYNXAFA-UHFFFAOYSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.85 Å
  • R-Value Free: 0.220 
  • R-Value Work: 0.173 
  • Space Group: P 41 21 2
Unit Cell:
Length (Å)Angle (°)
a = 108.920α = 90.00
b = 108.920β = 90.00
c = 93.390γ = 90.00
Software Package:
Software NamePurpose
REFMACrefinement
EPMRphasing
XDSdata reduction
XSCALEdata scaling

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2006-03-29
    Type: Initial release
  • Version 1.1: 2011-07-13
    Type: Advisory, Version format compliance