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Trimethylamine N-Oxide Reductase

  1. Chantal Iobbi-Nivol1,
  2. Richard Haser2,
  3. Vincent Méjean1,
  4. Mirjam Czjzek3

Published Online: 15 DEC 2011

DOI: 10.1002/9781119951438.eibc0604

Encyclopedia of Inorganic and Bioinorganic Chemistry

Encyclopedia of Inorganic and Bioinorganic Chemistry

How to Cite

Iobbi-Nivol, C., Haser, R., Méjean, V. and Czjzek, M. 2011. Trimethylamine N-Oxide Reductase. Encyclopedia of Inorganic and Bioinorganic Chemistry. .

Author Information

  1. 1

    IBSM, Laboratoire de Chimie Bactérienne, Marseille, France

  2. 2

    IBCP, Laboratoire de Bio-Christallographie, Lyon, France

  3. 3

    IBSM, Laboratoire d'Architecture et de Fonction des Macromolécules Biologiques, Marseille, France

Publication History

  1. Published Online: 15 DEC 2011


Trimethylamine N-oxide (TMAO) is a compound widely distributed in marine fish and invertebrates; and TMAO reducing enzymes are found not only in marine bacteria and photosynthetic bacteria living in ponds but also in enterobacteria. The various respiratory systems reducing TMAO, described so far, share a high level of homology either in their general structure, or in the regulation or mechanism of electron transfer. According to their content of molybdenum cofactor, the enzymes in charge of TMAO reduction are classified in the structural dimethylsulfoxide (DMSO) reductase family. TMAO reductases, however, in contrast to DMSO reductases are highly specific enzymes and reduce only their physiological substrate. The crystal structure was determined for the TMAO reductase from Shewanella massilia, and its structural differences with DMSO reductases in the environment of the active site. A tyrosine residue in the proximity of the molybdenum ion in DMSO reductases is absent in TMAO reductases and could be related to the differences in substrate specificities.

3D Structure


  • trimethylamine N-oxide reductase;
  • oxomolybdenum enzymes;
  • substrate specificity;
  • crystal structure;
  • marine bacteria