Trimethylamine N-oxide reductase

Simon, C. Mejean, V. Jourlin, C. Chippaux, M. Pascal, M.C. The torR gene of Escherichia coh encodes a response regulator protein involved in the expression of the trimethylamine N-oxide reductase genes. J. BacterioL, 176, 5601-5606 (1994)... 

Czjzek, M., Dos Santos, J.-P, Pommier, J., Giordano, G., MEJean, V., and Haser, R., 1998, Crystal structure of oxidized trimethylamine-N-oxide reductase from Shewanella massilia at 2.5 resolution, J. Mol. Biol. 284 43511447. 

DM SO reductase Biotin-S-oxide reductase Trimethylamine-N-oxide reductase Nitrate reductase (dissimilatory) Formate dehydrogenase... 

The structural analogy of trimethylamine N-oxide reductase (TMANOR) with the synthetic complex may be visualized by comparing the X-ray structures of the active site of the oxidized native protein from Shewanella mas-and of the model (Figure 3.12). 

A number of other reductases and dehydrogenases, including dissimilatory nitrate reductases of E. coli and of denitrifying bacteria (Chapter 18), belong to the DMSO reductase family. Other members are reductases for biotin S-oxide,649 trimethylamine N-oxide, and polysulfides as well as formate dehydrogenases (Eq. 16-63), formylmethanofuran dehydrogenase (Fig. 15-22,... 

Various bacteria grow anaerobically using trimethylamine-N-oxide (TMAO) as an alternative electron acceptor of a respiratory transport chain (31, 32). The energy-yielding reaction involves the conversion of TMAO to tetramethylamine (TMA) catalyzed by a TMAO reductase (TMAOR). 

King, G.F., D.J. Richardson, J.B. Jackson, and S.J. Ferguson. 1987. Dimethyl sulfoxide and trimethylamine-N-oxide as bacterial electron acceptors use of nuclear magnetic resonance to assay and characterize the reductase system in Rhodobacter capsulatus. Arch. Microbiol. 149 47-51. 

The above schemes work reasonably well for certain enzyme reactions, especially for substrates where oxygen addition/loss occurs at a main group element (e.g., N, S, Se, Cl, see Table I). In addition to SO and nitrate reductase, key examples are DMSOR, trimethylamine oxide reductase, chlorate reductase, and selenate reductase. In the case of enzymes catalyzing C-based redox reactions of organic molecules, notably XDH and aldehyde oxidase, a direct OAT step is unlikely and is replaced by mechanistic steps typical of hydro-xylation (2). The essential features of the mechanism are shown in Fig. 10 for xanthine dehydrogenase/oxidase. 

N Trimethylamine Oxide reductase E. coll 200, M 2Mo, iFe, 1.5Zn MeaNO/MeaN (312)... 

---