Molecular cloning, sequence analysis, and functional characterization of the lipopolysaccharide biosynthetic gene kdtA encoding 3-deoxy-alpha-D-manno-octulosonic acid transferase of Chlamydia pneumoniae strain TW-183

Mol Microbiol. 1995 Nov;18(3):391-9. doi: 10.1111/j.1365-2958.1995.mmi_18030391.x.


The gene kdtA of Chlamydia pneumoniae strain TW-183, encoding the enzyme 3-deoxy-alpha-D-manno-octulosonic acid (Kdo) transferase of lipopolysaccharide biosynthesis, was cloned and sequenced. A single open reading frame of 1314 bp was identified, the deduced amino acid sequence of which revealed 69% similarity and 43% identity with KdtA of Chlamydia trachomatis and Chlamydia psittaci. The gene was expressed in the Gram-positive host Corynebacterium glutamicum and the primary gene product was characterized as a multifunctional glycosyltransferase. Cell-free extracts generated in vitro the genus-specific epitope of Chlamydia composed of the trisaccharide alphaKdo(2-8)alphaKdo(2-4)alphaKdo. The results show that a single polypeptide affords three different glycosidic bonds, which is in contradiction to the dogma of glycobiology: 'one enzyme - one glycosidic bond'.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Base Sequence
  • Blotting, Western
  • Chlamydophila pneumoniae / genetics*
  • Cloning, Molecular
  • Corynebacterium / genetics
  • Epitopes
  • Gene Expression
  • Genes, Bacterial*
  • Molecular Sequence Data
  • Plasmids
  • Sequence Analysis
  • Sequence Homology, Amino Acid
  • Transferases / chemistry
  • Transferases / genetics*
  • Transferases / isolation & purification
  • Transferases / ultrastructure


  • Epitopes
  • Transferases
  • 3-deoxy-D-manno-octulosonate transferase