Purification, characterization, and cloning of an S-adenosylmethionine-dependent 3-amino-3-carboxypropyltransferase in nocardicin biosynthesis

J Biol Chem. 1998 Nov 13;273(46):30695-703. doi: 10.1074/jbc.273.46.30695.


S-Adenosylmethionine:nocardicin 3-amino-3-carboxypropyltransferase catalyzes the biosynthetically rare transfer of the 3-amino-3-carboxypropyl moiety from S-adenosylmethionine to a phenolic site in the beta-lactam substrates nocardicin E, F, and G, a late step of the biosynthesis of the monocyclic beta-lactam antibiotic nocardicin A. Whereas a number of conventional methods were ineffective in purifying the transferase, it was successfully obtained by two complementary affinity chromatography steps that took advantage of the two substrate-two product reaction scheme. S-Adenosylhomocysteine-agarose selected enzymes that utilize S-adenosylmethionine, and a second column, nocardicin A-agarose, specifically bound the desired transferase to yield the enzyme as a single band of 38 kDa on a silver-stained SDS-polyacrylamide gel. The transferase is active as a monomer and exhibits sequential kinetics. Further kinetic characterization of this protein is described and its role in the biosynthesis of nocardicin A discussed. The gene encoding this transferase was cloned from a sublibrary of Nocardia uniformis DNA. Translation gave a protein of deduced mass 32,386 Da which showed weak homology to small molecule methyltransferases. However, three correctly disposed signature motifs characteristic of these enzymes were observed.

Publication types

  • Research Support, U.S. Gov't, Non-P.H.S.
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Amino Acid Sequence
  • Aminoacyltransferases / genetics
  • Aminoacyltransferases / isolation & purification*
  • Anti-Bacterial Agents / biosynthesis*
  • Base Sequence
  • Binding Sites
  • Catalysis
  • Cloning, Molecular
  • DNA, Bacterial / chemistry
  • Lactams*
  • Molecular Sequence Data
  • Molecular Weight
  • Nocardia / enzymology*
  • Nocardia / metabolism
  • Polymerase Chain Reaction
  • S-Adenosylmethionine / metabolism*


  • Anti-Bacterial Agents
  • DNA, Bacterial
  • Lactams
  • nocardicin
  • S-Adenosylmethionine
  • Aminoacyltransferases
  • S-adenosylmethionine - nocardicin 3-amino-3-carboxypropyltransferase

Associated data

  • GENBANK/AP083882