Biological Assembly 1  

 3D View: Structure | Electron Density | Ligand Interaction

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Protein Workshop | Ligand Explorer

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

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

Biological Assembly 2  

 3D View: Structure | Electron Density | Ligand Interaction

Standalone Viewers  
Protein Workshop | Ligand Explorer

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

Biological assembly 2 assigned by authors and generated by PISA (software)

Macromolecule Content

• Total Structure Weight: 106193.16 
• Atom Count: 7456 
• Residue Count: 916 
• Unique protein chains: 1

1QWJ

The Crystal Structure of Murine CMP-5-N-Acetylneuraminic Acid Synthetase

• DOI: 10.2210/pdb1QWJ/pdb

• Classification: TRANSFERASE
• Organism(s): Mus musculus
• Expression System: Escherichia coli BL21


• Deposited: 2003-09-02 Released: 2003-12-09 
• Deposition Author(s): Krapp, S., Muenster-Kuehnel, A.K., Kaiser, J.T., Huber, R., Tiralongo, J., Gerardy-Schahn, R., Jacob, U.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 2.8 Å
• R-Value Free: 0.304 
• R-Value Work: 0.240 

Literature

The Crystal Structure of Murine CMP-5-N-acetylneuraminic Acid Synthetase

Krapp, S., Muenster-Kuehnel, A.K., Kaiser, J.T., Huber, R., Tiralongo, J., Gerardy-Schahn, R., Jacob, U.

(2003) J.Mol.Biol. 334: 625-637

• PubMed: 14636592 


• PubMed Abstract: 
  

Sialic acids are activated by CMP-5-N-acetylneuraminic acid synthetase prior to their transfer onto oligo- or polysaccharides. Here, we present the crystal structure of the N-terminal catalytically active domain of the murine 5-N-acetylneuraminic acid synthetase in complex with the reaction product. In contrast to the previously solved structure of 5-N-acetylneuraminic acid synthetase from Neisseria meningitidis and the related CMP-KDO-synthetase of Escherichia coli, the murine enzyme is a tetramer, which was observed with the active sites closed. In this conformation a loop is shifted by 6A towards the active site and thus an essential arginine residue can participate in catalysis. Furthermore, a network of intermolecular salt-bridges and hydrogen bonds in the dimer as well as hydrophobic interfaces between two dimers indicate a cooperative behaviour of the enzyme. In addition, a complex regulation of the enzyme activity is proposed that includes phosphorylation and dephosphorylation.

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Organizational Affiliation: 

Max-Planck-Institut für Biochemie, Abteilung für Strukturforschung, Am Klopferspitz 18a, 82152, Martinsried, Germany.

Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details
cytidine monophospho-N-acetylneuraminic acid synthetase	A, B, C, D	229	Mus musculus	Mutation(s): 0  Gene Names: Cmas EC: 2.7.7.43
Find proteins for Q99KK2 (Mus musculus) Go to UniProtKB:  Q99KK2

Small Molecules

Ligands 1 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram & Interactions
NCC	A, C, D	CYTIDINE-5'-MONOPHOSPHATE-5-N-ACETYLNEURAMINIC ACID C20 H31 N4 O16 P TXCIAUNLDRJGJZ-BILDWYJOSA-N

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 2.8 Å
• R-Value Free: 0.304 
• R-Value Work: 0.240 
• Space Group: P 2₁ 2₁ 2₁

Unit Cell:

Length (Å)	Angle (°)
a = 74.048	α = 90.00
b = 79.941	β = 90.00
c = 170.251	γ = 90.00

Software Package:

Software Name	Purpose
MOSFLM	data reduction
SCALA	data scaling
CNS	refinement
CCP4	data scaling
CNS	phasing

Structure Validation

Entry History 

Deposition Data

• Deposited Date: 2003-09-02 
• Released Date: 2003-12-09 
• Deposition Author(s): Krapp, S., Muenster-Kuehnel, A.K., Kaiser, J.T., Huber, R., Tiralongo, J., Gerardy-Schahn, R., Jacob, U.

Revision History 

• Version 1.0: 2003-12-09
  Type: Initial release
• Version 1.1: 2008-04-29
  Type: Version format compliance
• Version 1.2: 2011-07-13
  Type: Version format compliance