One-pot three-enzyme chemoenzymatic approach to the synthesis of sialosides containing natural and non-natural functionalities

Nat Protoc. 2006;1(5):2485-92. doi: 10.1038/nprot.2006.401.


Chemoenzymatic synthesis, which combines the flexibility of chemical synthesis and the high selectivity of enzymatic synthesis, is a powerful approach to obtain complex carbohydrates. It is a preferred method for synthesizing sialic acid-containing structures, including those with diverse naturally occurring and non-natural sialic acid forms, different sialyl linkages and different glycans that link to the sialic acid. Starting from N-acetylmannosamine, mannose or their chemically or enzymatically modified derivatives, sialic acid aldolase-catalyzed condensation reaction leads to the formation of sialic acids and their derivatives. These compounds are subsequently activated by a CMP-sialic acid synthetase and transferred to a wide range of suitable acceptors by a suitable sialyltransferase for the formation of sialosides containing natural and non-natural functionalities. The three-enzyme coupled synthesis of sialosides can be carried out in one pot without the isolation of intermediates. The time for synthesis is 4-18 h. Purification and characterization of the product can be completed within 2-3 d.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Escherichia coli K12 / enzymology
  • Oxo-Acid-Lyases / metabolism
  • Pasteurella multocida / enzymology
  • Photobacterium / enzymology
  • Sialic Acids / chemical synthesis*
  • Sialic Acids / chemistry*
  • Sialic Acids / isolation & purification
  • Sialyltransferases / metabolism
  • Trisaccharides / chemical synthesis*
  • Trisaccharides / chemistry
  • Trisaccharides / isolation & purification


  • Sialic Acids
  • Trisaccharides
  • Sialyltransferases
  • Oxo-Acid-Lyases
  • N-acetylneuraminate lyase