The enzyme participates exclusively in sulfur dissimilation. It has lower activity with diethyl sulfide and other short-chain alkyl methyl sulfides. Its activity is stimulated by combined addition of FMN, and, after depletion of cations, of Mg2+ and Fe2+. The enzymes from bacteria of the Hyphomicrobium genus are a two component system that includes an FMN-dependent reductase subunit and a monooxygenase subunit.