Biological Assembly 1  

 3D View: Structure | 1D-3D View | Validation Report | Ligand Interaction

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

Biological assembly 1 assigned by authors.

Macromolecule Content

• Total Structure Weight: 42.25 kDa 
• Atom Count: 2912 
• Modelled Residue Count: 377 
• Deposited Residue Count: 383 
• Unique protein chains: 1

1XRC

CRYSTAL STRUCTURE OF S-ADENOSYLMETHIONINE SYNTHETASE

• PDB DOI: 10.2210/pdb1XRC/pdb

• Classification: METHYLTRANSFERASE
• Organism(s): Escherichia coli
• Mutation(s): No 


• Deposited: 1995-10-26 Released: 1996-03-08 
• Deposition Author(s): Takusagawa, F., Kamitori, S., Misaki, S., Markham, G.D.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 3.00 Å
• R-Value Free: 0.258 
• R-Value Work: 0.197 
• R-Value Observed: 0.197 

Literature

Crystal structure of S-adenosylmethionine synthetase.

Takusagawa, F., Kamitori, S., Misaki, S., Markham, G.D.

(1996) J Biol Chem 271: 136-147

• PubMed: 8550549 
• Primary Citation of Related Structures:  
  1XRA, 1XRB, 1XRC


• PubMed Abstract: 
  

The structure of S-adenosylmethionine synthetase (MAT, ATP:L-methionine S-adenosyltransferase, EC 2.5.1.6.) from Escherichia coli has been determined at 3.0 A resolution by multiple isomorphous replacement using a uranium derivative and the selenomethionine form of the enzyme (SeMAT). The SeMAT data (9 selenomethionine residues out of 383 amino acid residues) have been found to have a sufficient phasing power to determine the structure of the 42,000 molecular weight protein by combining them with the other heavy atom derivative data (multiple isomorphous replacement). The enzyme consists of four identical subunits; two subunits form a spherical tight dimer, and pairs of these dimers form a peanut-shaped tetrameric enzyme. Each pair dimer has two active sites which are located between the subunits. Each subunit consists of three domains that are related to each other by pseudo-3-fold symmetry. The essential divalent (Mg2+/Co2+) and monovalent (K+) metal ions and one of the product, Pi ions, were found in the active site from three separate structures.

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Organizational Affiliation: 

Department of Chemistry, University of Kansas, Lawrence 66045-0046, USA.

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
S-ADENOSYLMETHIONINE SYNTHETASE	A	383	Escherichia coli	Mutation(s): 0  EC: 2.5.1.6
UniProt
Find proteins for P0A817 (Escherichia coli (strain K12)) Explore P0A817  Go to UniProtKB:  P0A817

Small Molecules

Ligands 3 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
PO4	B [auth A], C [auth A]	PHOSPHATE ION O4 P NBIIXXVUZAFLBC-UHFFFAOYSA-K
CO	D [auth A], E [auth A]	COBALT (II) ION Co XLJKHNWPARRRJB-UHFFFAOYSA-N
K	F [auth A], G [auth A]	POTASSIUM ION K NPYPAHLBTDXSSS-UHFFFAOYSA-N

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 3.00 Å
• R-Value Free: 0.258 
• R-Value Work: 0.197 
• R-Value Observed: 0.197 
• Space Group: P 6₂ 2 2

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 128.9	α = 90
b = 128.9	β = 90
c = 139.8	γ = 120

Software Package:

Software Name	Purpose
X-PLOR	model building
X-PLOR	refinement
X-PLOR	phasing

Structure Validation

Entry History 

Deposition Data

• Deposited Date: 1995-10-26 
• Released Date: 1996-03-08 
Deposition Author(s): Takusagawa, F., Kamitori, S., Misaki, S., Markham, G.D.

Revision History  

• Version 1.0: 1996-03-08
  Type: Initial release
  
• Version 1.1: 2008-03-24
  Changes: Version format compliance
• Version 1.2: 2011-07-13
  Changes: Version format compliance