Biological Assembly 1  

 3D View: Structure | Ligand Interaction

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

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

Macromolecule Content

• Total Structure Weight: 92613.33 
• Atom Count: 6432 
• Residue Count: 864 
• Unique protein chains: 1

4GSA

CRYSTAL STRUCTURE OF GLUTAMATE-1-SEMIALDEHYDE AMINOMUTASE (AMINOTRANSFERASE) REDUCED WITH CYANOBOROHYDRATE

• DOI: 10.2210/pdb4GSA/pdb

• Classification: CHLOROPHYLL BIOSYNTHESIS
• Organism(s): Synechococcus sp. (strain ATCC 27144 / PCC 6301 / SAUG 1402/1)
• Expression System: Escherichia coli


• Deposited: 1997-02-26 Released: 1998-03-04 
• Deposition Author(s): Hennig, M., Jansonius, J.N.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 2.5 Å
• R-Value Free: 0.264 
• R-Value Work: 0.187 

Literature

Crystal structure of glutamate-1-semialdehyde aminomutase: an alpha2-dimeric vitamin B6-dependent enzyme with asymmetry in structure and active site reactivity.

Hennig, M., Grimm, B., Contestabile, R., John, R.A., Jansonius, J.N.

(1997) Proc.Natl.Acad.Sci.USA 94: 4866-4871

• PubMed: 9144156 
• Primary Citation of Related Structures:  
  3GSB, 2GSA


• PubMed Abstract: 
  

The three-dimensional structure of glutamate-1-semialdehyde aminomutase (EC 5.4.3.8), an alpha2-dimeric enzyme from Synechococcus, has been determined by x-ray crystallography using heavy atom derivative phasing. The structure, refined at 2.4-A resolution to an R-factor of 18.7% and good stereochemistry, explains many of the enzyme's unusual specificity and functional properties. The overall fold is that of aspartate aminotransferase and related B6 enzymes, but it also has specific features. The structure of the complex with gabaculine, a substrate analogue, shows unexpectedly that the substrate binding site involves residues from the N-terminal domain of the molecule, notably Arg-32. Glu-406 is suitably positioned to repel alpha-carboxylic acids, thereby suggesting a basis for the enzyme's reaction specificity. The subunits show asymmetry in cofactor binding and in the mobilities of the residues 153-181. In the unliganded enzyme, one subunit has the cofactor bound as an aldimine of pyridoxal phosphate with Lys-273 and, in this subunit, residues 153-181 are disordered. In the other subunit in which the cofactor is not covalently bound, residues 153-181 are well defined. Consistent with the crystallographically demonstrated asymmetry, a form of the enzyme in which both subunits have pyridoxal phosphate bound to Lys-273 through a Schiff base showed biphasic reduction by borohydride in solution. Analysis of absorption spectra during reduction provided evidence of communication between the subunits. The crystal structure of the reduced form of the enzyme shows that, despite identical cofactor binding in each monomer, the structural asymmetry at residues 153-181 remains.

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Related Citations: 

• Crystallization and Preliminary X-Ray Analysis of Wild-Type and K272A Mutant Glutamate 1-Semialdehyde Aminotransferase from Synechococcus
  Hennig, M.,Grimm, B.,Jenny, M.,Muller, R.,Jansonius, J.N.
  (1994) J.Mol.Biol. 242: 591




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Organizational Affiliation: 

Biozentrum, University of Basel, Klingelbergstrasse 70, CH-4056 Basel, Switzerland.

Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details
GLUTAMATE SEMIALDEHYDE AMINOTRANSFERASE	A, B	432	Synechococcus sp. (strain ATCC 27144 / PCC 6301 / SAUG 1402/1)	Mutation(s): 0  Gene Names: hemL (gsa) EC: 5.4.3.8
Find proteins for P24630 (Synechococcus sp. (strain ATCC 27144 / PCC 6301 / SAUG 1402/1)) Go to UniProtKB:  P24630

Small Molecules

Ligands 1 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram & Interactions
PLP	A, B	PYRIDOXAL-5'-PHOSPHATE VITAMIN B6 Phosphate C8 H10 N O6 P NGVDGCNFYWLIFO-UHFFFAOYSA-N

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 2.5 Å
• R-Value Free: 0.264 
• R-Value Work: 0.187 
• Space Group: P 2₁ 2₁ 2₁

Unit Cell:

Length (Å)	Angle (°)
a = 68.640	α = 90.00
b = 108.280	β = 90.00
c = 122.440	γ = 90.00

Software Package:

Software Name	Purpose
X-PLOR	phasing
X-PLOR	refinement
X-PLOR	model building
CCP4	data scaling
MOSFLM	data reduction

Structure Validation

Entry History 

Deposition Data

• Deposited Date: 1997-02-26 
• Released Date: 1998-03-04 
• Deposition Author(s): Hennig, M., Jansonius, J.N.

Revision History 

• Version 1.0: 1998-03-04
  Type: Initial release
• Version 1.1: 2008-03-03
  Type: Version format compliance
• Version 1.2: 2011-07-13
  Type: Non-polymer description, Version format compliance