Dimethylsulfoxide reductases

Figure 17.6 The catalytic cycle of dimethylsulfoxide reductase. (From Hille, 2002. Copyright 2002, with permission from Elsevier.)...

Bilous PT, Cole ST, Anderson WF, Weiner JH. 1988. Nucleotide sequence of the dins ABC operon encoding the anaerobic dimethylsulfoxide reductase of Escherichia coli. Mol Microbiol 2 785-95. 

Two other families of molybdoenzymes are the sulfite oxidase family6463 13 and the dimethylsulfoxide reductase family.632 641 Nitrogenase (Chapter 24) constitutes a fourth family. Sulfite oxidase (Eq. 16-60) is an essential human liver enzyme (see also Chapter... 

Bennett, B., Benson, N., McEwan, A. G., and Bray, R. C., 1994, Multiple states of the molybdenum centre of dimethylsulfoxide reductase from Rhodobacter capsulatus revealed by EPR spectroscopy, Eur. J. Biochem. 225 321n331. 

Schultz, B. E., Hille, R., and Holm, R. H., 1995, Direct oxygen atom h ansfer in the mechanism of action of Rhodobacter sphaeroides dimethylsulfoxide reductase, J. Am. Chem. Soc. 117 827n828. 

Weiner, J. H., Macisaac, D. P., Bishop, R. E., and Bilous, P. T., 1988, Purification and properties of Escherichia coli dimethylsulfoxide reductase, an iron-sulfur molybdoenzyme with broad substrate specificity, J. Bacteriol. 270 2505n2520. 

Weiner, J. H., Rothery, R. A., Sambasivarao, D., and Trieber, C. A., 1992, Molecular analysis of dimethylsulfoxide reductase a complex iron-sulfur molybdoenzyme of Escherichia coli, Biochim. Biophys. Acta 1102 lnl2. 

The periplasmic dimethylsulfoxide reductases (DMSORs) of the photosynthetic bacteria R. capsulatus and R. sphaeroides function in a respiratory chain with DMSO as the terminal electron acceptor and catalyse the environmentally important Reaction (2). " ... 

Another interesting molybdenum-containing enzyme is dimethylsulfoxide reductase (Figure 20.6). It contains two molecules of bound molybdopterin covalently linked to a serine residue in the enzyme. 

See also The Nitrogen Cycle, Nitrogen Fixation, Utilization of Ammonia, Dimethylsulfoxide Reductase, Nitrite Reductase, Siroheme, Ferredoxin, Figure 20.2... 

Dimethylsulfoxide reductase is a molybdenum-containing enzyme that catalyzes the conversion of dimethyl sulfoniopropionate (DMSP), produced by marine algae as an osmotic stabilizer and methylating agent, to dimethyl sulfide (DMS) (Figure 20.6). DMS is subsequently oxidized to dimethylsulfoxide (DMSO). Dimethylsulfoxide reductase contains two molecules of bound molybdopterin covalently linked to a serine residue in the enzyme. 

Figure 1. Examples of redox cofactors found in metalloproteins. (a) [Fej-Sj] cluster, (b) [Fcs-Sj -" cluster (c) [Fc4-S4] - cluster (d) molybdenum cofactor in xanthine oxidase (e) molybdenum cofactor in dimethylsulfoxide reductase (f) heme prosthetic group (g) iron molybdenum cofactor in nitrogenase.

Hanlon, S.P., Graham, D.L, Hogan, P.J., Holt, RA., Reeve, C.D., Shad, A.L., and McEwan, A.G. (1998) Asymmetric reduction of racemic sulfoxides by dimethylsulfoxide reductases from Rhodobacter capsulatus, Escherichia coli and Proteus species. Microbiology, 144, 2247-2253. 

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