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Experiments were performed to examine the enantioselective reduction of racemic sulfoxides by dimethyl sulfoxide (DMSO) reductases from Rhodobacter capsulatus, Escherichia coli, Proteus mirabilis and P. vulgaris. It was shown that purified DMSO reductases from R. capsulatus acted as a catalyst in the selective removal of (S)-methyl p-tolyl sulfoxide from a racemic mixture of methyl p-tolyl sulfoxide resulting in an 88% recovery of enantiomerically pure (R)-methyl p-tolyl sulfoxide. On the other hand, the three bacteria reduced the sulfoxides with opposite enantioselectivity.

2-Phenylethylamine was converted to phenylacetic acid by Escherichia coli K-12 through the action of amine oxidase and aldehyde dehydrogenase. The compound phenylacetic acid is utilized by E. coli K-12 as carbon and energy source. Currently, a second amine oxidase gene is identified which is located near the gene encoding the 2-phenylethylamine oxidase. Results have shown that a gene which encodes a positive regulatory protein required for the expression of amine oxidase and phenylacetaldehyde dehydrogenase (PAD) gene was located next to the PAD genes.

The marine photosynthetic bacterium SH1 is a strain of Rhodobacter sulfidophilus, which uses dimethylsulphide (DMS) as an electron donor during photoautotrophic growth. The intermediate formation of dimethylsulphoxide (DMSO) during the growth of the SH1 strain reveals that DMS is an electron donor and not a source of energy. The zymogram staining patterns and gel filtration elution profile indicate that DMS acceptor oxidoreductase and DMSO reductase are two different enzymes, the former having a higher molecular mass than the latter.