Biological Assembly 1  

 3D View: Structure | Electron Density | Ligand Interaction

Global Symmetry: Cyclic - C2  (3D View)
Global Stoichiometry: Homo 2-mer - A2 

Biological assembly 1 assigned by authors and generated by PQS (software)

Macromolecule Content

• Total Structure Weight: 43.79 kDa 
• Atom Count: 2745 
• Residue Count: 360 
• Unique protein chains: 1

2CFB

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

• DOI: 10.2210/pdb2CFB/pdb

• Classification: ISOMERASE
• Organism(s): Synechococcus elongatus
• Expression System: Escherichia coli BL21
• Mutation(s): No 


• Deposited: 2006-02-17 Released: 2006-03-29 
• Deposition Author(s): Schulze, J.O., Schubert, W.-D., Moser, J., Jahn, D., Heinz, D.W.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 2.85 Å
• R-Value Free: 0.220 
• R-Value Work: 0.173 
• R-Value Observed: 0.176 

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

• PubMed: 16564539 
• DOI: 10.1016/j.jmb.2006.02.064
• Primary Citation of Related Structures:  
  2CFB


• 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 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.

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Organizational Affiliation: 

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

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
GLUTAMATE-1-SEMIALDEHYDE 2,1-AMINOMUTASE	A	411	Synechococcus elongatus	Mutation(s): 0  EC: 5.4.3.8
Find proteins for Q8DLK8 (Thermosynechococcus elongatus (strain BP-1)) Explore Q8DLK8  Go to UniProtKB:  Q8DLK8

Small Molecules

Ligands 1 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
PLR	A	(5-HYDROXY-4,6-DIMETHYLPYRIDIN-3-YL)METHYL DIHYDROGEN PHOSPHATE C8 H12 N O5 P RBCOYOYDYNXAFA-UHFFFAOYSA-N

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 2.85 Å
• R-Value Free: 0.220 
• R-Value Work: 0.173 
• R-Value Observed: 0.176 
• Space Group: P 4₁ 2₁ 2

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 108.92	α = 90
b = 108.92	β = 90
c = 93.39	γ = 90

Software Package:

Software Name	Purpose
REFMAC	refinement
XDS	data reduction
XSCALE	data scaling
EPMR	phasing

Structure Validation

Entry History 

Deposition Data

• Deposited Date: 2006-02-17 
• Released Date: 2006-03-29 
Deposition Author(s): Schulze, J.O., Schubert, W.-D., Moser, J., Jahn, D., Heinz, D.W.

Revision History 

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