CMP-N-acetylneuraminic Acid Hydroxylase: The First Cytosolic Rieske Iron-Sulphur Protein to Be Described in Eukarya

FEBS Lett. 1996 May 6;385(3):197-200. doi: 10.1016/0014-5793(96)00384-5.


Electron paramagnetic resonance (EPR) spectroscopy and analysis of the primary structure of the CMP-N-acetylneuraminic acid hydroxylase revealed that this enzyme is the first iron-sulphur protein of the Rieske type to be found in the cytosol of Eukarya. The dithionite-reduced hydroxylase exhibited an EPR signal known to be characteristic for a Rieske iron-sulphur centre (2Fe-2S), the g-values being 1.78, 1.91 and 2.01, respectively. An analysis of the primary structure of the hydroxylase led to the identification of an amino acid sequence, known to be characteristic for Rieske proteins. Furthermore, possible binding sites for cytochrome b5, the substrate CMP-Neu5Ac and a mononuclear iron centre were also identified.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Base Sequence
  • Binding Sites
  • Cloning, Molecular
  • Cytochromes b5 / metabolism
  • Cytoplasm / enzymology
  • Dithionite / pharmacology
  • Electron Spin Resonance Spectroscopy
  • Electron Transport Complex III*
  • Eukaryotic Cells / enzymology*
  • Evolution, Molecular
  • Iron-Sulfur Proteins / chemistry*
  • Iron-Sulfur Proteins / genetics
  • Iron-Sulfur Proteins / metabolism
  • Mixed Function Oxygenases / chemistry*
  • Mixed Function Oxygenases / genetics
  • Mixed Function Oxygenases / metabolism
  • Molecular Sequence Data
  • N-Acetylneuraminic Acid
  • Sequence Homology, Amino Acid
  • Sialic Acids / metabolism
  • Submandibular Gland / enzymology*
  • Swine


  • Iron-Sulfur Proteins
  • Rieske iron-sulfur protein
  • Sialic Acids
  • Dithionite
  • Cytochromes b5
  • Mixed Function Oxygenases
  • CMPacetylneuraminate monooxygenase
  • Electron Transport Complex III
  • N-Acetylneuraminic Acid

Associated data

  • GENBANK/Y15010