Trimethylamine N-oxide reductase
Encyclopedia
Trimethylamine N-oxide reductase (TOR or TMAO reductase, EC 1.7.2.3) is a microbial enzyme that can reduce trimethylamine N-oxide
(TMAO) into trimethylamine
(TMA), as part of the electron transport chain
. The enzyme has been purified from E. coli and the photosynthetic bacteria Roseobacter denitrificans. Both the R. denitrificans and E. coli enzymes can accept electrons from cytochrome
s.
trimethylamine + 2 (ferricytochrome c)-subunit + H2O → trimethylamine N-oxide + 2 (ferrocytochrome c)-subunit + 2 H+
Trimethylamine oxide is found at high concentrations in the tissues of fish, and the bacterial reduction of this compound to foul-smelling trimethylamine is a major process in the spoilage of fish.
Trimethylamine N-oxide
Trimethylamine N-oxide, also known by several other names and acronyms, is the organic compound with the formula 3NO. This colorless solid is usually encountered as the dihydrate. It is an oxidation product of trimethylamine and a common metabolite in animals. It is an osmolyte found in saltwater...
(TMAO) into trimethylamine
Trimethylamine
Trimethylamine is an organic compound with the formula N3. This colorless, hygroscopic, and flammable tertiary amine has a strong "fishy" odor in low concentrations and an ammonia-like odor at higher concentrations...
(TMA), as part of the electron transport chain
Electron transport chain
An electron transport chain couples electron transfer between an electron donor and an electron acceptor with the transfer of H+ ions across a membrane. The resulting electrochemical proton gradient is used to generate chemical energy in the form of adenosine triphosphate...
. The enzyme has been purified from E. coli and the photosynthetic bacteria Roseobacter denitrificans. Both the R. denitrificans and E. coli enzymes can accept electrons from cytochrome
Cytochrome
Cytochromes are, in general, membrane-bound hemoproteins that contain heme groups and carry out electron transport.They are found either as monomeric proteins or as subunits of bigger enzymatic complexes that catalyze redox reactions....
s.
trimethylamine + 2 (ferricytochrome c)-subunit + H2O → trimethylamine N-oxide + 2 (ferrocytochrome c)-subunit + 2 H+
Trimethylamine oxide is found at high concentrations in the tissues of fish, and the bacterial reduction of this compound to foul-smelling trimethylamine is a major process in the spoilage of fish.