Large-scale domain motions and pyridoxal-5'-phosphate assisted radical catalysis in coenzyme B12-dependent aminomutases

Int J Mol Sci. 2014 Feb 20;15(2):3064-87. doi: 10.3390/ijms15023064.


Lysine 5,6-aminomutase (5,6-LAM) and ornithine 4,5-aminomutase (4,5-OAM) are two of the rare enzymes that use assistance of two vitamins as cofactors. These enzymes employ radical generating capability of coenzyme B12 (5'-deoxyadenosylcobalamin, dAdoCbl) and ability of pyridoxal-5'-phosphate (PLP, vitamin B6) to stabilize high-energy intermediates for performing challenging 1,2-amino rearrangements between adjacent carbons. A large-scale domain movement is required for interconversion between the catalytically inactive open form and the catalytically active closed form. In spite of all the similarities, these enzymes differ in substrate specificities. 4,5-OAM is highly specific for D-ornithine as a substrate while 5,6-LAM can accept D-lysine and L-β-lysine. This review focuses on recent computational, spectroscopic and structural studies of these enzymes and their implications on the related enzymes. Additionally, we also discuss the potential biosynthetic application of 5,6-LAM.

Publication types

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

MeSH terms

  • Binding Sites
  • Biocatalysis
  • Cobamides / chemistry
  • Cobamides / metabolism*
  • Intramolecular Transferases / chemistry
  • Intramolecular Transferases / genetics
  • Intramolecular Transferases / metabolism*
  • Molecular Docking Simulation
  • Protein Structure, Tertiary
  • Pyridoxal Phosphate / chemistry
  • Pyridoxal Phosphate / metabolism*
  • Recombinant Proteins / biosynthesis
  • Recombinant Proteins / chemistry
  • Recombinant Proteins / genetics


  • Cobamides
  • Recombinant Proteins
  • Pyridoxal Phosphate
  • Intramolecular Transferases
  • ornithine 5,4-aminomutase
  • cobamamide