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

Experimental Data Snapshot

  • Resolution: 2.80 Å
  • R-Value Free: 0.304 
  • R-Value Work: 0.240 

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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

  • DOI: https://doi.org/10.1016/j.jmb.2003.09.080
  • Primary Citation of Related Structures:  

  • 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.

  • Organizational Affiliation

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

Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
cytidine monophospho-N-acetylneuraminic acid synthetase
A, B, C, D
229Mus musculusMutation(s): 0 
Gene Names: Cmas
UniProt & NIH Common Fund Data Resources
Find proteins for Q99KK2 (Mus musculus)
Explore Q99KK2 
Go to UniProtKB:  Q99KK2
IMPC:  MGI:1337124
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupQ99KK2
Sequence Annotations
  • Reference Sequence
Experimental Data & Validation

Experimental Data

  • Resolution: 2.80 Å
  • R-Value Free: 0.304 
  • R-Value Work: 0.240 
  • Space Group: P 21 21 21
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 74.048α = 90
b = 79.941β = 90
c = 170.251γ = 90
Software Package:
Software NamePurpose
MOSFLMdata reduction
SCALAdata scaling
CCP4data scaling

Structure Validation

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Ligand Structure Quality Assessment 

Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 2003-12-09
    Type: Initial release
  • Version 1.1: 2008-04-29
    Changes: Version format compliance
  • Version 1.2: 2011-07-13
    Changes: Version format compliance
  • Version 1.3: 2024-02-14
    Changes: Data collection, Database references, Derived calculations
  • Version 1.4: 2024-04-03
    Changes: Refinement description